1. does condition predict donations?

a. raw donated

summary(m1 <- lmer(donate ~ indiv_1 + charity_1 + (indiv_1 + charity_1 | participant) + (1 | stimulus),
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 100000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ indiv_1 + charity_1 + (indiv_1 + charity_1 | participant) +  
##     (1 | stimulus)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 1e+05))
## 
## REML criterion at convergence: -6459
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.0574 -0.4435 -0.0785  0.2429  5.7846 
## 
## Random effects:
##  Groups      Name        Variance  Std.Dev. Corr     
##  participant (Intercept) 9.628e-03 0.098123          
##              indiv_1     7.087e-03 0.084183 0.77     
##              charity_1   7.300e-03 0.085441 0.67 0.91
##  stimulus    (Intercept) 4.279e-05 0.006541          
##  Residual                2.633e-02 0.162251          
## Number of obs: 9828, groups:  participant, 378; stimulus, 21
## 
## Fixed effects:
##             Estimate Std. Error       df t value Pr(>|t|)    
## (Intercept) 0.115520   0.008937 9.028766  12.926 3.95e-07 ***
## indiv_1     0.072178   0.009186 8.337363   7.857 3.95e-05 ***
## charity_1   0.066646   0.009217 8.448168   7.231 6.81e-05 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##           (Intr) indv_1
## indiv_1   -0.458       
## charity_1 -0.480  0.848
summary(m2 <- lmer(donate ~ pract_1 + charity_1 + (pract_1 + charity_1 | participant) + (1 | stimulus),
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 100000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ pract_1 + charity_1 + (pract_1 + charity_1 | participant) +  
##     (1 | stimulus)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 1e+05))
## 
## REML criterion at convergence: -6459
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.0574 -0.4435 -0.0785  0.2429  5.7846 
## 
## Random effects:
##  Groups      Name        Variance  Std.Dev. Corr       
##  participant (Intercept) 2.942e-02 0.171515            
##              pract_1     7.087e-03 0.084183 -0.93      
##              charity_1   1.257e-03 0.035452 -0.21  0.17
##  stimulus    (Intercept) 4.279e-05 0.006541            
##  Residual                2.633e-02 0.162251            
## Number of obs: 9828, groups:  participant, 378; stimulus, 21
## 
## Fixed effects:
##               Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)   0.187698   0.009438 303.975061  19.888  < 2e-16 ***
## pract_1      -0.072178   0.009186   8.337351  -7.857 3.95e-05 ***
## charity_1    -0.005532   0.005080  23.050532  -1.089    0.287    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##           (Intr) prct_1
## pract_1   -0.540       
## charity_1 -0.304  0.270
summary(m3 <- lmer(donate ~ pract_1 + indiv_1 + (indiv_1 + pract_1 | participant),
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 100000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ pract_1 + indiv_1 + (indiv_1 + pract_1 | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 1e+05))
## 
## REML criterion at convergence: -6456.6
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.0330 -0.4495 -0.0798  0.2411  5.7928 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr       
##  participant (Intercept) 0.028166 0.16783             
##              indiv_1     0.001250 0.03536   0.00      
##              pract_1     0.007291 0.08539  -0.90  0.24
##  Residual                0.026359 0.16235             
## Number of obs: 9828, groups:  participant, 378
## 
## Fixed effects:
##               Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)   0.182167   0.009027 393.417752  20.180   <2e-16 ***
## pract_1      -0.066646   0.006155 409.930194 -10.828   <2e-16 ***
## indiv_1       0.005532   0.004154 393.417998   1.332    0.184    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##         (Intr) prct_1
## pract_1 -0.741       
## indiv_1 -0.186  0.348
tab_model(m1, m2, m3)
  donate donate donate
Predictors Estimates CI p Estimates CI p Estimates CI p
(Intercept) 0.12 0.10 – 0.13 <0.001 0.19 0.17 – 0.21 <0.001 0.18 0.16 – 0.20 <0.001
indiv_1 0.07 0.05 – 0.09 <0.001 0.01 -0.00 – 0.01 0.183
charity_1 0.07 0.05 – 0.08 <0.001 -0.01 -0.02 – 0.00 0.276
pract_1 -0.07 -0.09 – -0.05 <0.001 -0.07 -0.08 – -0.05 <0.001
Random Effects
σ2 0.03 0.03 0.03
τ00 0.01 participant 0.03 participant 0.03 participant
0.00 stimulus 0.00 stimulus  
τ11 0.01 participant.indiv_1 0.01 participant.pract_1 0.00 participant.indiv_1
0.01 participant.charity_1 0.00 participant.charity_1 0.01 participant.pract_1
ρ01 0.77 participant.indiv_1 -0.93 participant.pract_1 -0.00
0.67 participant.charity_1 -0.21 participant.charity_1 -0.90
ICC 0.48 0.48 0.48
N 378 participant 378 participant 378 participant
21 stimulus 21 stimulus  
Observations 9828 9828 9828
Marginal R2 / Conditional R2 0.017 / 0.490 0.017 / 0.490 0.017 / 0.489

b. proportion donated

singular random intercepts for stimulus

summary(m4 <- lmer(propDonate ~ indiv_1 + charity_1 + (indiv_1 + charity_1 | participant),
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 100000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ indiv_1 + charity_1 + (indiv_1 + charity_1 | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 1e+05))
## 
## REML criterion at convergence: -3361.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -4.7629 -0.3035 -0.0273  0.2403  5.0872 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr     
##  participant (Intercept) 0.04671  0.2161            
##              indiv_1     0.03234  0.1798   0.16     
##              charity_1   0.03400  0.1844   0.10 0.82
##  Residual                0.03240  0.1800            
## Number of obs: 9828, groups:  participant, 378
## 
## Fixed effects:
##              Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)   0.22262    0.01174 376.99978  18.960   <2e-16 ***
## indiv_1       0.10333    0.01041 377.00014   9.924   <2e-16 ***
## charity_1     0.09376    0.01062 377.00049   8.828   <2e-16 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##           (Intr) indv_1
## indiv_1    0.016       
## charity_1 -0.028  0.780
summary(m5 <- lmer(propDonate ~ pract_1 + charity_1 + (pract_1 + charity_1 | participant),
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 100000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ pract_1 + charity_1 + (pract_1 + charity_1 | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 1e+05))
## 
## REML criterion at convergence: -3361.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -4.7629 -0.3035 -0.0273  0.2403  5.0872 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr       
##  participant (Intercept) 0.09129  0.3021              
##              pract_1     0.03234  0.1798   -0.71      
##              charity_1   0.01189  0.1091   -0.22  0.26
##  Residual                0.03240  0.1800              
## Number of obs: 9828, groups:  participant, 378
## 
## Fixed effects:
##               Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)   0.325947   0.015814 376.999200  20.611   <2e-16 ***
## pract_1      -0.103330   0.010412 376.999394  -9.924   <2e-16 ***
## charity_1    -0.009566   0.006972 376.999890  -1.372    0.171    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##           (Intr) prct_1
## pract_1   -0.670       
## charity_1 -0.249  0.304
summary(m6 <- lmer(propDonate ~ pract_1 + indiv_1 + (indiv_1 + pract_1 | participant),
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 100000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ pract_1 + indiv_1 + (indiv_1 + pract_1 | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 1e+05))
## 
## REML criterion at convergence: -3361.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -4.7629 -0.3035 -0.0273  0.2403  5.0872 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr       
##  participant (Intercept) 0.08892  0.2982              
##              indiv_1     0.01189  0.1091   -0.15      
##              pract_1     0.03400  0.1844   -0.69  0.34
##  Residual                0.03240  0.1800              
## Number of obs: 9828, groups:  participant, 378
## 
## Fixed effects:
##               Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)   0.316381   0.015615 376.999713  20.262   <2e-16 ***
## pract_1      -0.093764   0.010621 376.999985  -8.828   <2e-16 ***
## indiv_1       0.009566   0.006972 376.999948   1.372    0.171    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##         (Intr) prct_1
## pract_1 -0.660       
## indiv_1 -0.194  0.358
tab_model(m4, m5, m6)
  propDonate propDonate propDonate
Predictors Estimates CI p Estimates CI p Estimates CI p
(Intercept) 0.22 0.20 – 0.25 <0.001 0.33 0.29 – 0.36 <0.001 0.32 0.29 – 0.35 <0.001
indiv_1 0.10 0.08 – 0.12 <0.001 0.01 -0.00 – 0.02 0.170
charity_1 0.09 0.07 – 0.11 <0.001 -0.01 -0.02 – 0.00 0.170
pract_1 -0.10 -0.12 – -0.08 <0.001 -0.09 -0.11 – -0.07 <0.001
Random Effects
σ2 0.03 0.03 0.03
τ00 0.05 participant 0.09 participant 0.09 participant
τ11 0.03 participant.indiv_1 0.03 participant.pract_1 0.01 participant.indiv_1
0.03 participant.charity_1 0.01 participant.charity_1 0.03 participant.pract_1
ρ01 0.16 -0.71 -0.15
0.10 -0.22 -0.69
ICC 0.71 0.71 0.71
N 378 participant 378 participant 378 participant
Observations 9828 9828 9828
Marginal R2 / Conditional R2 0.015 / 0.716 0.015 / 0.716 0.015 / 0.716

2. do people donate more when allocated more money?

a. raw donated

singular with money.c random slopes

summary(m7 <- lmer(donate ~ (indiv_1 + charity_1) * money.c + (indiv_1 + charity_1 | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ (indiv_1 + charity_1) * money.c + (indiv_1 + charity_1 |  
##     participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -9297.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -4.0659 -0.5861 -0.0534  0.4791  5.7562 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr     
##  participant (Intercept) 0.010854 0.10418           
##              indiv_1     0.009049 0.09513  0.52     
##              charity_1   0.009262 0.09624  0.44 0.85
##  Residual                0.018968 0.13772           
## Number of obs: 9828, groups:  participant, 378
## 
## Fixed effects:
##                    Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)       1.253e-01  6.109e-03 3.818e+02  20.507  < 2e-16 ***
## indiv_1           5.819e-02  6.129e-03 3.820e+02   9.493  < 2e-16 ***
## charity_1         5.275e-02  6.175e-03 3.820e+02   8.543 3.17e-16 ***
## money.c           2.224e-01  1.111e-02 8.691e+03  20.014  < 2e-16 ***
## indiv_1:money.c   9.999e-02  1.383e-02 8.691e+03   7.228 5.32e-13 ***
## charity_1:money.c 9.250e-02  1.383e-02 8.691e+03   6.686 2.44e-11 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) indv_1 chrt_1 mony.c in_1:.
## indiv_1      0.132                            
## charity_1    0.080  0.772                     
## money.c      0.080 -0.079 -0.079              
## indv_1:mny. -0.064  0.053  0.063 -0.803       
## chrty_1:mn. -0.064  0.064  0.053 -0.803  0.645
summary(m8 <- lmer(donate ~ (pract_1 + charity_1) * money.c + (pract_1 + charity_1 | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ (pract_1 + charity_1) * money.c + (pract_1 + charity_1 |  
##     participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -9297.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -4.0659 -0.5861 -0.0534  0.4791  5.7562 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr       
##  participant (Intercept) 0.030153 0.17365             
##              pract_1     0.009049 0.09513  -0.86      
##              charity_1   0.002728 0.05223  -0.22  0.25
##  Residual                0.018968 0.13772             
## Number of obs: 9828, groups:  participant, 378
## 
## Fixed effects:
##                     Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)        1.835e-01  9.209e-03  3.771e+02  19.922  < 2e-16 ***
## pract_1           -5.819e-02  6.129e-03  3.820e+02  -9.493  < 2e-16 ***
## charity_1         -5.433e-03  4.157e-03  3.780e+02  -1.307    0.192    
## money.c            3.224e-01  8.241e-03  8.691e+03  39.119  < 2e-16 ***
## pract_1:money.c   -9.999e-02  1.383e-02  8.691e+03  -7.228 5.32e-13 ***
## charity_1:money.c -7.497e-03  1.166e-02  8.691e+03  -0.643    0.520    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) prct_1 chrt_1 mony.c pr_1:.
## pract_1     -0.753                            
## charity_1   -0.269  0.328                     
## money.c     -0.012  0.018  0.026              
## prct_1:mny.  0.007  0.053 -0.016 -0.596       
## chrty_1:mn.  0.008 -0.013 -0.037 -0.707  0.421
tab_model(m7, m8)
  donate donate
Predictors Estimates CI p Estimates CI p
(Intercept) 0.13 0.11 – 0.14 <0.001 0.18 0.17 – 0.20 <0.001
indiv_1 0.06 0.05 – 0.07 <0.001
charity_1 0.05 0.04 – 0.06 <0.001 -0.01 -0.01 – 0.00 0.191
money.c 0.22 0.20 – 0.24 <0.001 0.32 0.31 – 0.34 <0.001
indiv_1 * money.c 0.10 0.07 – 0.13 <0.001
charity_1 * money.c 0.09 0.07 – 0.12 <0.001 -0.01 -0.03 – 0.02 0.520
pract_1 -0.06 -0.07 – -0.05 <0.001
pract_1 * money.c -0.10 -0.13 – -0.07 <0.001
Random Effects
σ2 0.02 0.02
τ00 0.01 participant 0.03 participant
τ11 0.01 participant.indiv_1 0.01 participant.pract_1
0.01 participant.charity_1 0.00 participant.charity_1
ρ01 0.52 -0.86
0.44 -0.22
ICC 0.57 0.57
N 378 participant 378 participant
Observations 9828 9828
Marginal R2 / Conditional R2 0.144 / 0.632 0.144 / 0.632

b. proportion donated

summary(m9 <- lmer(propDonate ~ (indiv_1 + charity_1) * money.c + (indiv_1 + charity_1 + money.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ (indiv_1 + charity_1) * money.c + (indiv_1 + charity_1 +  
##     money.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -3360.6
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -4.7916 -0.3035 -0.0321  0.2403  5.1241 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr             
##  participant (Intercept) 0.046946 0.21667                   
##              indiv_1     0.032676 0.18076   0.15            
##              charity_1   0.034262 0.18510   0.10  0.82      
##              money.c     0.005801 0.07616   0.11 -0.15 -0.10
##  Residual                0.031937 0.17871                   
## Number of obs: 9828, groups:  participant, 378
## 
## Fixed effects:
##                     Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)        2.225e-01  1.178e-02  3.787e+02  18.891   <2e-16 ***
## indiv_1            1.036e-01  1.046e-02  3.789e+02   9.901   <2e-16 ***
## charity_1          9.399e-02  1.066e-02  3.788e+02   8.819   <2e-16 ***
## money.c           -3.551e-03  1.494e-02  3.891e+03  -0.238    0.812    
## indiv_1:money.c   -1.497e-03  1.795e-02  8.314e+03  -0.083    0.934    
## charity_1:money.c -1.661e-03  1.795e-02  8.314e+03  -0.093    0.926    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) indv_1 chrt_1 mony.c in_1:.
## indiv_1      0.008                            
## charity_1   -0.034  0.782                     
## money.c      0.080 -0.093 -0.080              
## indv_1:mny. -0.043  0.041  0.048 -0.775       
## chrty_1:mn. -0.043  0.049  0.040 -0.775  0.645
summary(m10 <- lmer(propDonate ~ (pract_1 + charity_1) * money.c + (pract_1 + charity_1 + money.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ (pract_1 + charity_1) * money.c + (pract_1 + charity_1 +  
##     money.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -3360.6
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -4.7916 -0.3035 -0.0321  0.2403  5.1241 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr             
##  participant (Intercept) 0.091341 0.30223                   
##              pract_1     0.032676 0.18076  -0.71            
##              charity_1   0.011988 0.10949  -0.22  0.26      
##              money.c     0.005801 0.07616  -0.01  0.15  0.08
##  Residual                0.031937 0.17871                   
## Number of obs: 9828, groups:  participant, 378
## 
## Fixed effects:
##                     Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)        3.260e-01  1.581e-02  3.770e+02  20.614   <2e-16 ***
## pract_1           -1.036e-01  1.046e-02  3.789e+02  -9.901   <2e-16 ***
## charity_1         -9.564e-03  6.975e-03  3.776e+02  -1.371    0.171    
## money.c           -5.048e-03  1.139e-02  1.651e+03  -0.443    0.658    
## pract_1:money.c    1.497e-03  1.795e-02  8.314e+03   0.083    0.934    
## charity_1:money.c -1.642e-04  1.512e-02  8.314e+03  -0.011    0.991    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) prct_1 chrt_1 mony.c pr_1:.
## pract_1     -0.668                            
## charity_1   -0.249  0.305                     
## money.c     -0.011  0.058  0.042              
## prct_1:mny.  0.005  0.041 -0.012 -0.559       
## chrty_1:mn.  0.006 -0.010 -0.029 -0.664  0.421
tab_model(m9, m10)
  propDonate propDonate
Predictors Estimates CI p Estimates CI p
(Intercept) 0.22 0.20 – 0.25 <0.001 0.33 0.30 – 0.36 <0.001
indiv_1 0.10 0.08 – 0.12 <0.001
charity_1 0.09 0.07 – 0.11 <0.001 -0.01 -0.02 – 0.00 0.170
money.c -0.00 -0.03 – 0.03 0.812 -0.01 -0.03 – 0.02 0.658
indiv_1 * money.c -0.00 -0.04 – 0.03 0.934
charity_1 * money.c -0.00 -0.04 – 0.03 0.926 -0.00 -0.03 – 0.03 0.991
pract_1 -0.10 -0.12 – -0.08 <0.001
pract_1 * money.c 0.00 -0.03 – 0.04 0.934
Random Effects
σ2 0.03 0.03
τ00 0.05 participant 0.09 participant
τ11 0.03 participant.indiv_1 0.03 participant.pract_1
0.03 participant.charity_1 0.01 participant.charity_1
0.01 participant.money.c 0.01 participant.money.c
ρ01 0.15 -0.71
0.10 -0.22
0.11 -0.01
ICC 0.72 0.72
N 378 participant 378 participant
Observations 9828 9828
Marginal R2 / Conditional R2 0.015 / 0.720 0.015 / 0.720

5. do people donate more when stimluli are in greater need?

a. raw donated

singular with need.c random slopes

summary(m11 <- lmer(donate ~ (indiv_1 + charity_1) * need.c + (indiv_1 + charity_1  | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ (indiv_1 + charity_1) * need.c + (indiv_1 + charity_1 |  
##     participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -7466.3
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.3677 -0.5030 -0.0963  0.3431  5.4545 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr     
##  participant (Intercept) 0.006651 0.08156           
##              indiv_1     0.004793 0.06923  0.90     
##              charity_1   0.005180 0.07198  0.90 0.93
##  Residual                0.024062 0.15512           
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                   Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)      1.473e-01  5.782e-03 4.498e+02  25.468  < 2e-16 ***
## indiv_1          3.144e-02  5.929e-03 4.595e+02   5.303 1.77e-07 ***
## charity_1        1.788e-02  6.059e-03 4.775e+02   2.952  0.00332 ** 
## need.c           3.060e-02  2.204e-03 5.439e+02  13.883  < 2e-16 ***
## indiv_1:need.c   1.212e-02  2.647e-03 9.194e+02   4.580 5.30e-06 ***
## charity_1:need.c 1.073e-02  2.680e-03 9.478e+02   4.005 6.68e-05 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) indv_1 chrt_1 need.c in_1:.
## indiv_1     -0.071                            
## charity_1   -0.058  0.788                     
## need.c       0.395 -0.391 -0.388              
## indv_1:nd.c -0.306  0.265  0.286 -0.775       
## chrty_1:nd. -0.303  0.292  0.221 -0.765  0.673
summary(m12 <- lmer(donate ~ (pract_1 + charity_1) * need.c + (pract_1 + charity_1 | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ (pract_1 + charity_1) * need.c + (pract_1 + charity_1 |  
##     participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -7466.3
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.3677 -0.5030 -0.0963  0.3431  5.4545 
## 
## Random effects:
##  Groups      Name        Variance  Std.Dev. Corr       
##  participant (Intercept) 0.0216369 0.14709             
##              pract_1     0.0047931 0.06923  -0.97      
##              charity_1   0.0007369 0.02715   0.00  0.09
##  Residual                0.0240625 0.15512             
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                    Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)       1.787e-01  7.983e-03  3.735e+02  22.385  < 2e-16 ***
## pract_1          -3.144e-02  5.929e-03  4.596e+02  -5.303 1.77e-07 ***
## charity_1        -1.356e-02  3.901e-03  3.892e+02  -3.477 0.000565 ***
## need.c            4.272e-02  1.681e-03  3.715e+03  25.410  < 2e-16 ***
## pract_1:need.c   -1.212e-02  2.647e-03  9.194e+02  -4.580 5.30e-06 ***
## charity_1:need.c -1.390e-03  2.156e-03  1.685e+03  -0.645 0.519223    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) prct_1 chrt_1 need.c pr_1:.
## pract_1     -0.691                            
## charity_1   -0.207  0.295                     
## need.c      -0.044  0.095  0.054              
## prct_1:nd.c  0.025  0.265 -0.041 -0.559       
## chrty_1:nd.  0.027 -0.037 -0.174 -0.617  0.392
tab_model(m11, m12)
  donate donate
Predictors Estimates CI p Estimates CI p
(Intercept) 0.15 0.14 – 0.16 <0.001 0.18 0.16 – 0.19 <0.001
indiv_1 0.03 0.02 – 0.04 <0.001
charity_1 0.02 0.01 – 0.03 0.003 -0.01 -0.02 – -0.01 0.001
need.c 0.03 0.03 – 0.03 <0.001 0.04 0.04 – 0.05 <0.001
indiv_1 * need.c 0.01 0.01 – 0.02 <0.001
charity_1 * need.c 0.01 0.01 – 0.02 <0.001 -0.00 -0.01 – 0.00 0.519
pract_1 -0.03 -0.04 – -0.02 <0.001
pract_1 * need.c -0.01 -0.02 – -0.01 <0.001
Random Effects
σ2 0.02 0.02
τ00 0.01 participant 0.02 participant
τ11 0.00 participant.indiv_1 0.00 participant.pract_1
0.01 participant.charity_1 0.00 participant.charity_1
ρ01 0.90 -0.97
0.90 -0.00
ICC 0.43 0.43
N 378 participant 378 participant
Observations 9827 9827
Marginal R2 / Conditional R2 0.118 / 0.501 0.118 / 0.501
################################

mplot <- lmer(donate ~ condition * need.c + (condition | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d)

(p <- plot_model(mplot, type = "pred", 
                terms = c("need.c", "condition")) +
  ggtitle("") + 
  ylab("proportion donated") +
  xlab("mean-centered need rating") +
  theme_minimal() +
  theme(panel.grid.major = element_blank(), 
        panel.grid.minor = element_blank(),
        panel.background = element_blank(), 
        axis.line = element_line(colour = "black"),
        legend.position = c(.5, .8), 
        legend.direction = "horizontal", 
        legend.box = "horizontal",
        legend.background = element_rect(fill = "white", color = "white"),
        legend.title = element_blank()) +
  scale_color_manual(
    labels = c("charity","individual", "practice"),
    values = c("blue", "red", "purple")) +
  scale_fill_manual(values = c("blue", "red", "purple")) +
  scale_x_continuous(breaks = c(-2.5, -2, -1.5, -1, -.5, 0, .5, 1, 1.5, 2, 2.5), 
                     limits = c(-2.5, 3)) +
  scale_y_continuous(breaks = c(0, .10, .20, .30, .40), 
                     limits = c(0, .4)))
## Scale for 'colour' is already present. Adding another scale for 'colour',
## which will replace the existing scale.
## Scale for 'y' is already present. Adding another scale for 'y', which will
## replace the existing scale.
## Warning: Removed 3 row(s) containing missing values (geom_path).

b. proportion donated

summary(m13 <- lmer(propDonate ~ (indiv_1 + charity_1) * need.c + (indiv_1 + charity_1 + need.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ (indiv_1 + charity_1) * need.c + (indiv_1 + charity_1 +  
##     need.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -7239.2
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -6.0469 -0.3095 -0.0332  0.2562  6.3841 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr             
##  participant (Intercept) 0.052873 0.22994                   
##              indiv_1     0.015099 0.12288  -0.09            
##              charity_1   0.019118 0.13827  -0.16  0.75      
##              need.c      0.003384 0.05817   0.62  0.06 -0.11
##  Residual                0.020328 0.14258                   
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                   Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)      2.666e-01  1.283e-02 4.056e+02  20.781  < 2e-16 ***
## indiv_1          3.416e-02  8.381e-03 3.852e+02   4.076 5.58e-05 ***
## charity_1        1.093e-02  9.035e-03 3.931e+02   1.210    0.227    
## need.c           5.003e-02  4.610e-03 9.271e+02  10.852  < 2e-16 ***
## indiv_1:need.c   2.157e-02  3.779e-03 1.205e+03   5.707 1.45e-08 ***
## charity_1:need.c 2.492e-02  3.871e-03 1.337e+03   6.437 1.70e-10 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) indv_1 chrt_1 need.c in_1:.
## indiv_1     -0.275                            
## charity_1   -0.312  0.766                     
## need.c       0.579 -0.300 -0.365              
## indv_1:nd.c -0.247  0.359  0.348 -0.660       
## chrty_1:nd. -0.249  0.370  0.303 -0.650  0.800
summary(m14 <- lmer(propDonate ~ (pract_1 + charity_1) * need.c + (pract_1 + charity_1 + need.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ (pract_1 + charity_1) * need.c + (pract_1 + charity_1 +  
##     need.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -7239.2
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -6.0469 -0.3095 -0.0332  0.2562  6.3841 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr             
##  participant (Intercept) 0.063153 0.25130                   
##              pract_1     0.015099 0.12288  -0.41            
##              charity_1   0.008767 0.09363  -0.21  0.21      
##              need.c      0.003384 0.05817   0.60 -0.06 -0.25
##  Residual                0.020328 0.14258                   
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                    Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)       3.008e-01  1.326e-02  3.695e+02  22.687  < 2e-16 ***
## pract_1          -3.416e-02  8.381e-03  3.852e+02  -4.076 5.58e-05 ***
## charity_1        -2.323e-02  5.988e-03  3.821e+02  -3.879 0.000123 ***
## need.c            7.159e-02  3.539e-03  4.699e+02  20.230  < 2e-16 ***
## pract_1:need.c   -2.157e-02  3.779e-03  1.205e+03  -5.707 1.45e-08 ***
## charity_1:need.c  3.352e-03  2.419e-03  3.796e+03   1.386 0.165935    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) prct_1 chrt_1 need.c pr_1:.
## pract_1     -0.366                            
## charity_1   -0.237  0.244                     
## need.c       0.470  0.008 -0.145              
## prct_1:nd.c  0.012  0.359 -0.023 -0.208       
## chrty_1:nd.  0.008 -0.031 -0.134 -0.311  0.281
tab_model(m13, m14)
  propDonate propDonate
Predictors Estimates CI p Estimates CI p
(Intercept) 0.27 0.24 – 0.29 <0.001 0.30 0.27 – 0.33 <0.001
indiv_1 0.03 0.02 – 0.05 <0.001
charity_1 0.01 -0.01 – 0.03 0.226 -0.02 -0.03 – -0.01 <0.001
need.c 0.05 0.04 – 0.06 <0.001 0.07 0.06 – 0.08 <0.001
indiv_1 * need.c 0.02 0.01 – 0.03 <0.001
charity_1 * need.c 0.02 0.02 – 0.03 <0.001 0.00 -0.00 – 0.01 0.166
pract_1 -0.03 -0.05 – -0.02 <0.001
pract_1 * need.c -0.02 -0.03 – -0.01 <0.001
Random Effects
σ2 0.02 0.02
τ00 0.05 participant 0.06 participant
τ11 0.02 participant.indiv_1 0.02 participant.pract_1
0.02 participant.charity_1 0.01 participant.charity_1
0.00 participant.need.c 0.00 participant.need.c
ρ01 -0.09 -0.41
-0.16 -0.21
0.62 0.60
ICC 0.78 0.78
N 378 participant 378 participant
Observations 9827 9827
Marginal R2 / Conditional R2 0.149 / 0.812 0.149 / 0.812
mplot <- lmer(propDonate ~ condition * need.c + (condition + need.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d)


(p <- plot_model(mplot, type = "pred", 
                terms = c("need.c", "condition")) +
  ggtitle("") + 
  ylab("proportion donated") +
  xlab("mean-centered need rating") +
  theme_minimal() +
  theme(panel.grid.major = element_blank(), 
        panel.grid.minor = element_blank(),
        panel.background = element_blank(), 
        axis.line = element_line(colour = "black"),
        legend.position = c(.5, .2), 
        legend.direction = "horizontal", 
        legend.box = "horizontal",
        legend.background = element_rect(fill = "white", color = "white"),
        legend.title = element_blank()) +
  scale_color_manual(
    labels = c("charity","individual", "practice"),
    values = c("blue", "red", "purple")) +
  scale_fill_manual(values = c("blue", "red", "purple")) +
  scale_x_continuous(breaks = c(-2.5, -2, -1.5, -1, -.5, 0, .5, 1, 1.5, 2, 2.5), 
                     limits = c(-2.5, 3)) +
  scale_y_continuous(breaks = c(0, .10, .20, .30, .40, .50, .6), 
                     limits = c(0, .6)))
## Scale for 'colour' is already present. Adding another scale for 'colour',
## which will replace the existing scale.
## Scale for 'y' is already present. Adding another scale for 'y', which will
## replace the existing scale.
## Warning: Removed 3 row(s) containing missing values (geom_path).

6. do people donate more when givig makes a greater difference?

a. raw donated

summary(m15 <- lmer(donate ~ (indiv_1 + charity_1) * diff.c + (indiv_1 + charity_1 + diff.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ (indiv_1 + charity_1) * diff.c + (indiv_1 + charity_1 +  
##     diff.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -7523.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.4161 -0.4084 -0.0702  0.2069  6.2214 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr          
##  participant (Intercept) 0.008878 0.09423                
##              indiv_1     0.005802 0.07617  0.76          
##              charity_1   0.005556 0.07454  0.69 0.95     
##              diff.c      0.001508 0.03883  0.58 0.04 0.03
##  Residual                0.023000 0.15166                
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                   Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)      1.450e-01  6.368e-03 3.428e+02  22.774  < 2e-16 ***
## indiv_1          4.627e-02  5.929e-03 3.717e+02   7.804 6.14e-14 ***
## charity_1        3.469e-02  5.901e-03 3.600e+02   5.878 9.45e-09 ***
## diff.c           4.483e-02  3.242e-03 3.937e+02  13.827  < 2e-16 ***
## indiv_1:diff.c   2.307e-03  2.797e-03 8.196e+02   0.825    0.410    
## charity_1:diff.c 1.509e-03  2.792e-03 7.640e+02   0.541    0.589    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) indv_1 chrt_1 diff.c in_1:.
## indiv_1      0.028                            
## charity_1   -0.015  0.793                     
## diff.c       0.530 -0.165 -0.175              
## indv_1:dff. -0.183  0.171  0.172 -0.509       
## chrty_1:df. -0.190  0.186  0.157 -0.529  0.738
summary(m16 <- lmer(donate ~ (pract_1 + charity_1) * diff.c + (pract_1 + charity_1 + diff.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ (pract_1 + charity_1) * diff.c + (pract_1 + charity_1 +  
##     diff.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -7523.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.4161 -0.4084 -0.0702  0.2069  6.2214 
## 
## Random effects:
##  Groups      Name        Variance  Std.Dev. Corr             
##  participant (Intercept) 0.0255249 0.15977                   
##              pract_1     0.0058021 0.07617  -0.92            
##              charity_1   0.0005883 0.02425  -0.26  0.23      
##              diff.c      0.0015079 0.03883   0.36 -0.04 -0.04
##  Residual                0.0229995 0.15166                   
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                    Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)        0.191283   0.008822 367.611031  21.682  < 2e-16 ***
## pract_1           -0.046269   0.005929 371.687500  -7.804 6.14e-14 ***
## charity_1         -0.011582   0.003803 378.111539  -3.046  0.00248 ** 
## diff.c             0.047139   0.003017 353.629492  15.623  < 2e-16 ***
## pract_1:diff.c    -0.002307   0.002797 819.576123  -0.825  0.40975    
## charity_1:diff.c  -0.000798   0.002023 735.736810  -0.395  0.69331    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) prct_1 chrt_1 diff.c pr_1:.
## pract_1     -0.692                            
## charity_1   -0.270  0.328                     
## diff.c       0.276  0.019 -0.014              
## prct_1:dff.  0.017  0.171 -0.001 -0.380       
## chrty_1:df.  0.007 -0.020 -0.065 -0.366  0.364
tab_model(m15, m16)
  donate donate
Predictors Estimates CI p Estimates CI p
(Intercept) 0.15 0.13 – 0.16 <0.001 0.19 0.17 – 0.21 <0.001
indiv_1 0.05 0.03 – 0.06 <0.001
charity_1 0.03 0.02 – 0.05 <0.001 -0.01 -0.02 – -0.00 0.002
diff.c 0.04 0.04 – 0.05 <0.001 0.05 0.04 – 0.05 <0.001
indiv_1 * diff.c 0.00 -0.00 – 0.01 0.410
charity_1 * diff.c 0.00 -0.00 – 0.01 0.589 -0.00 -0.00 – 0.00 0.693
pract_1 -0.05 -0.06 – -0.03 <0.001
pract_1 * diff.c -0.00 -0.01 – 0.00 0.410
Random Effects
σ2 0.02 0.02
τ00 0.01 participant 0.03 participant
τ11 0.01 participant.indiv_1 0.01 participant.pract_1
0.01 participant.charity_1 0.00 participant.charity_1
0.00 participant.diff.c 0.00 participant.diff.c
ρ01 0.76 -0.92
0.69 -0.26
0.58 0.36
ICC 0.53 0.53
N 378 participant 378 participant
Observations 9827 9827
Marginal R2 / Conditional R2 0.139 / 0.598 0.139 / 0.598
####################################################

mplot <- lmer(donate ~ condition * diff.c + (condition + diff.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d)


(p <- plot_model(mplot, type = "pred", 
                terms = c("condition")) +
  ggtitle("") + 
  ylab("donated") +
  xlab("condition") +
  theme_minimal() +
  theme(panel.grid.major = element_blank(), 
        panel.grid.minor = element_blank(),
        panel.background = element_blank(), 
        axis.line = element_line(colour = "black"),
        legend.position = c(.5, .2), 
        legend.direction = "horizontal", 
        legend.box = "horizontal",
        legend.background = element_rect(fill = "white", color = "white"),
        legend.title = element_blank()) +
  scale_fill_manual(values = c("blue", "red", "purple")) +
  scale_y_continuous(breaks = c(0, .10, .20, .30, .40, .5), 
                     limits = c(0, .5)))
## Scale for 'colour' is already present. Adding another scale for 'colour',
## which will replace the existing scale.
## Scale for 'y' is already present. Adding another scale for 'y', which will
## replace the existing scale.

b. proportion donated

summary(m17 <- lmer(propDonate ~ (indiv_1 + charity_1) * diff.c + (indiv_1 + charity_1 + diff.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ (indiv_1 + charity_1) * diff.c + (indiv_1 + charity_1 +  
##     diff.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -6224.4
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -5.4664 -0.3022 -0.0244  0.2402  6.2612 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr          
##  participant (Intercept) 0.051698 0.22737                
##              indiv_1     0.028345 0.16836  0.11          
##              charity_1   0.028681 0.16936  0.06 0.84     
##              diff.c      0.007507 0.08664  0.50 0.07 0.06
##  Residual                0.022087 0.14862                
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                   Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)      2.734e-01  1.281e-02 3.562e+02  21.349  < 2e-16 ***
## indiv_1          6.820e-02  9.917e-03 3.880e+02   6.877 2.45e-11 ***
## charity_1        4.757e-02  9.989e-03 3.806e+02   4.762 2.73e-06 ***
## diff.c           6.390e-02  5.980e-03 4.739e+02  10.684  < 2e-16 ***
## indiv_1:diff.c   2.640e-02  4.132e-03 1.493e+03   6.389 2.23e-10 ***
## charity_1:diff.c 2.413e-02  4.162e-03 1.499e+03   5.797 8.20e-09 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) indv_1 chrt_1 diff.c in_1:.
## indiv_1     -0.040                            
## charity_1   -0.079  0.811                     
## diff.c       0.508 -0.090 -0.094              
## indv_1:dff. -0.144  0.175  0.178 -0.484       
## chrty_1:df. -0.149  0.186  0.168 -0.495  0.790
summary(m18 <- lmer(propDonate ~ (pract_1 + charity_1) * diff.c + (pract_1 + charity_1 + diff.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ (pract_1 + charity_1) * diff.c + (pract_1 + charity_1 +  
##     diff.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -6224.4
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -5.4664 -0.3022 -0.0244  0.2402  6.2612 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr             
##  participant (Intercept) 0.088465 0.29743                   
##              pract_1     0.028345 0.16836  -0.65            
##              charity_1   0.009191 0.09587  -0.22  0.27      
##              diff.c      0.007507 0.08664   0.42 -0.07 -0.01
##  Residual                0.022087 0.14862                   
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                    Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)       3.416e-01  1.588e-02  3.655e+02  21.514  < 2e-16 ***
## pract_1          -6.820e-02  9.917e-03  3.880e+02  -6.877 2.45e-11 ***
## charity_1        -2.064e-02  6.114e-03  3.798e+02  -3.375 0.000814 ***
## diff.c            9.030e-02  5.379e-03  3.242e+02  16.786  < 2e-16 ***
## pract_1:diff.c   -2.640e-02  4.132e-03  1.493e+03  -6.389 2.23e-10 ***
## charity_1:diff.c -2.270e-03  2.688e-03  1.482e+03  -0.844 0.398612    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) prct_1 chrt_1 diff.c pr_1:.
## pract_1     -0.592                            
## charity_1   -0.237  0.296                     
## diff.c       0.388 -0.035 -0.005              
## prct_1:dff.  0.007  0.175 -0.007 -0.230       
## chrty_1:df.  0.004 -0.019 -0.053 -0.266  0.314
tab_model(m17, m18)
  propDonate propDonate
Predictors Estimates CI p Estimates CI p
(Intercept) 0.27 0.25 – 0.30 <0.001 0.34 0.31 – 0.37 <0.001
indiv_1 0.07 0.05 – 0.09 <0.001
charity_1 0.05 0.03 – 0.07 <0.001 -0.02 -0.03 – -0.01 0.001
diff.c 0.06 0.05 – 0.08 <0.001 0.09 0.08 – 0.10 <0.001
indiv_1 * diff.c 0.03 0.02 – 0.03 <0.001
charity_1 * diff.c 0.02 0.02 – 0.03 <0.001 -0.00 -0.01 – 0.00 0.398
pract_1 -0.07 -0.09 – -0.05 <0.001
pract_1 * diff.c -0.03 -0.03 – -0.02 <0.001
Random Effects
σ2 0.02 0.02
τ00 0.05 participant 0.09 participant
τ11 0.03 participant.indiv_1 0.03 participant.pract_1
0.03 participant.charity_1 0.01 participant.charity_1
0.01 participant.diff.c 0.01 participant.diff.c
ρ01 0.11 -0.65
0.06 -0.22
0.50 0.42
ICC 0.82 0.82
N 378 participant 378 participant
Observations 9827 9827
Marginal R2 / Conditional R2 0.169 / 0.855 0.169 / 0.855
#########################################

mplot <- lmer(propDonate ~ condition * diff.c + (condition + diff.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d)

(p <- plot_model(mplot, type = "pred", 
                terms = c("diff.c", "condition")) +
  ggtitle("") + 
  ylab("proportion donated") +
  xlab("mean-centered difference rating") +
  theme_minimal() +
  theme(panel.grid.major = element_blank(), 
        panel.grid.minor = element_blank(),
        panel.background = element_blank(), 
        axis.line = element_line(colour = "black"),
        legend.position = c(.5, .2), 
        legend.direction = "horizontal", 
        legend.box = "horizontal",
        legend.background = element_rect(fill = "white", color = "white"),
        legend.title = element_blank()) +
  scale_color_manual(
    labels = c("charity","individual", "practice"),
    values = c("blue", "red", "purple")) +
  scale_fill_manual(values = c("blue", "red", "purple")) +
  scale_x_continuous(breaks = c(-2.5, -2, -1.5, -1, -.5, 0, .5, 1, 1.5, 2, 2.5), 
                     limits = c(-2, 2)) +
  scale_y_continuous(breaks = c(0, .10, .20, .30, .40, .50, .6), 
                     limits = c(0, .6)))
## Scale for 'colour' is already present. Adding another scale for 'colour',
## which will replace the existing scale.
## Scale for 'y' is already present. Adding another scale for 'y', which will
## replace the existing scale.
## Warning: Removed 9 row(s) containing missing values (geom_path).

7. is there an interaction with condition and money allocated while controlling need and difference made

a. raw donated

summary(m15 <- lmer(donate ~ (indiv_1 + charity_1) * money.c + need.c + diff.c + 
                      (indiv_1 + charity_1 + diff.c + money.c + need.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ (indiv_1 + charity_1) * money.c + need.c + diff.c +  
##     (indiv_1 + charity_1 + diff.c + money.c + need.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -15832.9
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -7.6753 -0.3386 -0.0286  0.2685  7.8021 
## 
## Random effects:
##  Groups      Name        Variance  Std.Dev. Corr                         
##  participant (Intercept) 0.0150814 0.12281                               
##              indiv_1     0.0045513 0.06746   0.04                        
##              charity_1   0.0053696 0.07328  -0.05  0.74                  
##              diff.c      0.0007508 0.02740   0.15 -0.15 -0.14            
##              money.c     0.0755429 0.27485   0.83  0.42  0.33 -0.16      
##              need.c      0.0007198 0.02683   0.71  0.13 -0.10 -0.11  0.62
##  Residual                0.0082539 0.09085                               
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                     Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)        1.674e-01  6.837e-03  3.655e+02  24.488   <2e-16 ***
## indiv_1            1.038e-02  4.486e-03  3.373e+02   2.315   0.0212 *  
## charity_1         -2.877e-03  4.769e-03  3.478e+02  -0.603   0.5467    
## money.c            2.014e-01  1.598e-02  5.468e+02  12.599   <2e-16 ***
## need.c             2.872e-02  1.707e-03  3.533e+02  16.820   <2e-16 ***
## diff.c             1.938e-02  1.949e-03  2.471e+02   9.946   <2e-16 ***
## indiv_1:money.c    1.192e-01  9.297e-03  7.867e+03  12.821   <2e-16 ***
## charity_1:money.c  1.202e-01  9.292e-03  7.852e+03  12.935   <2e-16 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) indv_1 chrt_1 mony.c need.c diff.c in_1:.
## indiv_1     -0.139                                          
## charity_1   -0.199  0.727                                   
## money.c      0.698  0.260  0.206                            
## need.c       0.579 -0.022 -0.175  0.451                     
## diff.c       0.165 -0.092 -0.091 -0.130 -0.262              
## indv_1:mny. -0.032  0.042  0.049 -0.374 -0.009  0.049       
## chrty_1:mn. -0.030  0.051  0.037 -0.375 -0.007  0.051  0.645
summary(m16 <- lmer(donate ~ (pract_1 + charity_1) * money.c + need.c + diff.c + 
                      (pract_1 + charity_1 + diff.c + money.c + need.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ (pract_1 + charity_1) * money.c + need.c + diff.c +  
##     (pract_1 + charity_1 + diff.c + money.c + need.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -15832.9
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -7.6753 -0.3386 -0.0286  0.2685  7.8021 
## 
## Random effects:
##  Groups      Name        Variance  Std.Dev. Corr                         
##  participant (Intercept) 0.0202944 0.14246                               
##              pract_1     0.0045513 0.06746  -0.51                        
##              charity_1   0.0025626 0.05062  -0.23  0.26                  
##              diff.c      0.0007508 0.02740   0.06  0.15  0.00            
##              money.c     0.0755429 0.27485   0.92 -0.42 -0.08 -0.16      
##              need.c      0.0007198 0.02683   0.67 -0.13 -0.32 -0.11  0.62
##  Residual                0.0082539 0.09085                               
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                     Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)        1.778e-01  7.639e-03  3.627e+02  23.276  < 2e-16 ***
## pract_1           -1.038e-02  4.486e-03  3.373e+02  -2.315 0.021240 *  
## charity_1         -1.326e-02  3.432e-03  3.744e+02  -3.864 0.000131 ***
## money.c            3.206e-01  1.519e-02  4.466e+02  21.108  < 2e-16 ***
## need.c             2.872e-02  1.707e-03  3.533e+02  16.820  < 2e-16 ***
## diff.c             1.939e-02  1.949e-03  2.471e+02   9.946  < 2e-16 ***
## pract_1:money.c   -1.192e-01  9.297e-03  7.867e+03 -12.821  < 2e-16 ***
## charity_1:money.c  9.902e-04  7.827e-03  7.855e+03   0.127 0.899335    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) prct_1 chrt_1 mony.c need.c diff.c pr_1:.
## pract_1     -0.463                                          
## charity_1   -0.260  0.298                                   
## money.c      0.816 -0.299 -0.049                            
## need.c       0.505  0.022 -0.214  0.469                     
## diff.c       0.093  0.092 -0.005 -0.107 -0.262              
## prct_1:mny.  0.004  0.042 -0.012 -0.218  0.009 -0.049       
## chrty_1:mn.  0.007 -0.010 -0.032 -0.258  0.002  0.003  0.422
tab_model(m15, m16)
  donate donate
Predictors Estimates CI p Estimates CI p
(Intercept) 0.17 0.15 – 0.18 <0.001 0.18 0.16 – 0.19 <0.001
indiv_1 0.01 0.00 – 0.02 0.021
charity_1 -0.00 -0.01 – 0.01 0.546 -0.01 -0.02 – -0.01 <0.001
money.c 0.20 0.17 – 0.23 <0.001 0.32 0.29 – 0.35 <0.001
need.c 0.03 0.03 – 0.03 <0.001 0.03 0.03 – 0.03 <0.001
diff.c 0.02 0.02 – 0.02 <0.001 0.02 0.02 – 0.02 <0.001
indiv_1 * money.c 0.12 0.10 – 0.14 <0.001
charity_1 * money.c 0.12 0.10 – 0.14 <0.001 0.00 -0.01 – 0.02 0.899
pract_1 -0.01 -0.02 – -0.00 0.021
pract_1 * money.c -0.12 -0.14 – -0.10 <0.001
Random Effects
σ2 0.01 0.01
τ00 0.02 participant 0.02 participant
τ11 0.00 participant.indiv_1 0.00 participant.pract_1
0.01 participant.charity_1 0.00 participant.charity_1
0.00 participant.diff.c 0.00 participant.diff.c
0.08 participant.money.c 0.08 participant.money.c
0.00 participant.need.c 0.00 participant.need.c
ρ01 0.04 -0.51
-0.05 -0.23
0.15 0.06
0.83 0.92
0.71 0.67
ICC 0.78 0.78
N 378 participant 378 participant
Observations 9827 9827
Marginal R2 / Conditional R2 0.256 / 0.836 0.256 / 0.836

b. proportion donated

summary(m17 <- lmer(propDonate ~ (indiv_1 + charity_1) * money.c + need.c + diff.c + 
                      (indiv_1 + charity_1 + money.c + need.c + diff.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ (indiv_1 + charity_1) * money.c + need.c + diff.c +  
##     (indiv_1 + charity_1 + money.c + need.c + diff.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -8072
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -6.4102 -0.3149 -0.0248  0.2524  6.1190 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr                         
##  participant (Intercept) 0.050832 0.22546                               
##              indiv_1     0.016355 0.12789  -0.09                        
##              charity_1   0.020152 0.14196  -0.18  0.80                  
##              money.c     0.003838 0.06195  -0.25  0.09  0.10            
##              need.c      0.002669 0.05166   0.63  0.11 -0.06 -0.20      
##              diff.c      0.003297 0.05742   0.24 -0.12 -0.11 -0.48  0.02
##  Residual                0.017623 0.13275                               
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                     Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)        3.004e-01  1.237e-02  3.641e+02  24.287  < 2e-16 ***
## indiv_1            1.268e-02  7.903e-03  3.295e+02   1.604  0.10966    
## charity_1         -1.192e-02  8.577e-03  3.472e+02  -1.389  0.16564    
## money.c           -4.511e-02  1.142e-02  3.674e+03  -3.950 7.95e-05 ***
## need.c             5.124e-02  3.155e-03  3.609e+02  16.241  < 2e-16 ***
## diff.c             4.456e-02  3.815e-03  2.645e+02  11.682  < 2e-16 ***
## indiv_1:money.c    3.853e-02  1.368e-02  8.001e+03   2.816  0.00488 ** 
## charity_1:money.c  5.380e-02  1.367e-02  7.973e+03   3.936 8.36e-05 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) indv_1 chrt_1 mony.c need.c diff.c in_1:.
## indiv_1     -0.190                                          
## charity_1   -0.256  0.778                                   
## money.c     -0.033 -0.029 -0.022                            
## need.c       0.542 -0.002 -0.131 -0.034                     
## diff.c       0.227 -0.088 -0.082 -0.158 -0.155              
## indv_1:mny. -0.026  0.034  0.038 -0.771 -0.010  0.047       
## chrty_1:mn. -0.024  0.041  0.029 -0.772 -0.009  0.051  0.646
summary(m18 <- lmer(propDonate ~ (pract_1 + charity_1) * money.c + need.c + diff.c + 
                      (pract_1 + charity_1 + money.c + need.c + diff.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ (pract_1 + charity_1) * money.c + need.c + diff.c +  
##     (pract_1 + charity_1 + money.c + need.c + diff.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -8072
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -6.4102 -0.3149 -0.0248  0.2524  6.1190 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr                         
##  participant (Intercept) 0.062064 0.24913                               
##              pract_1     0.016355 0.12789  -0.43                        
##              charity_1   0.007304 0.08546  -0.23  0.16                  
##              money.c     0.003838 0.06195  -0.18 -0.09  0.04            
##              need.c      0.002669 0.05166   0.63 -0.11 -0.28 -0.20      
##              diff.c      0.003297 0.05742   0.16  0.12  0.00 -0.48  0.02
##  Residual                0.017623 0.13275                               
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                     Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)        3.131e-01  1.335e-02  3.647e+02  23.452  < 2e-16 ***
## pract_1           -1.268e-02  7.903e-03  3.295e+02  -1.604  0.10966    
## charity_1         -2.459e-02  5.525e-03  3.726e+02  -4.451 1.13e-05 ***
## money.c           -6.580e-03  8.765e-03  1.593e+03  -0.751  0.45294    
## need.c             5.124e-02  3.155e-03  3.609e+02  16.241  < 2e-16 ***
## diff.c             4.456e-02  3.815e-03  2.645e+02  11.682  < 2e-16 ***
## pract_1:money.c   -3.853e-02  1.368e-02  8.001e+03  -2.816  0.00488 ** 
## charity_1:money.c  1.527e-02  1.151e-02  7.997e+03   1.326  0.18483    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) prct_1 chrt_1 mony.c need.c diff.c pr_1:.
## pract_1     -0.415                                          
## charity_1   -0.248  0.222                                   
## money.c     -0.069 -0.015  0.027                            
## need.c       0.501  0.002 -0.200 -0.060                     
## diff.c       0.159  0.088 -0.002 -0.133 -0.155              
## prct_1:mny.  0.004  0.034 -0.011 -0.557  0.010 -0.047       
## chrty_1:mn.  0.007 -0.008 -0.029 -0.659  0.001  0.004  0.422
tab_model(m17, m18)
  propDonate propDonate
Predictors Estimates CI p Estimates CI p
(Intercept) 0.30 0.28 – 0.32 <0.001 0.31 0.29 – 0.34 <0.001
indiv_1 0.01 -0.00 – 0.03 0.109
charity_1 -0.01 -0.03 – 0.00 0.165 -0.02 -0.04 – -0.01 <0.001
money.c -0.05 -0.07 – -0.02 <0.001 -0.01 -0.02 – 0.01 0.453
need.c 0.05 0.05 – 0.06 <0.001 0.05 0.05 – 0.06 <0.001
diff.c 0.04 0.04 – 0.05 <0.001 0.04 0.04 – 0.05 <0.001
indiv_1 * money.c 0.04 0.01 – 0.07 0.005
charity_1 * money.c 0.05 0.03 – 0.08 <0.001 0.02 -0.01 – 0.04 0.185
pract_1 -0.01 -0.03 – 0.00 0.109
pract_1 * money.c -0.04 -0.07 – -0.01 0.005
Random Effects
σ2 0.02 0.02
τ00 0.05 participant 0.06 participant
τ11 0.02 participant.indiv_1 0.02 participant.pract_1
0.02 participant.charity_1 0.01 participant.charity_1
0.00 participant.money.c 0.00 participant.money.c
0.00 participant.need.c 0.00 participant.need.c
0.00 participant.diff.c 0.00 participant.diff.c
ρ01 -0.09 -0.43
-0.18 -0.23
-0.25 -0.18
0.63 0.63
0.24 0.16
ICC 0.82 0.82
N 378 participant 378 participant
Observations 9827 9827
Marginal R2 / Conditional R2 0.196 / 0.853 0.196 / 0.853

8. is there an interaction with condition and need while controlling money allocted and difference made

a. raw donated

summary(m15 <- lmer(donate ~ (indiv_1 + charity_1) * need.c + diff.c + money.c + 
                      (indiv_1 + charity_1 + diff.c + money.c + need.c | participant) + (1 | stimulus),  
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ (indiv_1 + charity_1) * need.c + diff.c + money.c +  
##     (indiv_1 + charity_1 + diff.c + money.c + need.c | participant) +  
##     (1 | stimulus)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -15690.3
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -7.5314 -0.3313 -0.0259  0.2600  7.8652 
## 
## Random effects:
##  Groups      Name        Variance  Std.Dev. Corr                         
##  participant (Intercept) 1.606e-02 0.126725                              
##              indiv_1     4.128e-03 0.064249 -0.02                        
##              charity_1   5.064e-03 0.071164 -0.11  0.73                  
##              diff.c      7.480e-04 0.027350  0.09 -0.08 -0.06            
##              money.c     7.543e-02 0.274649  0.88  0.28  0.20 -0.17      
##              need.c      7.144e-04 0.026729  0.72  0.09 -0.14 -0.15  0.65
##  stimulus    (Intercept) 1.291e-05 0.003592                              
##  Residual                8.419e-03 0.091753                              
## Number of obs: 9827, groups:  participant, 378; stimulus, 21
## 
## Fixed effects:
##                   Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)      1.543e-01  8.113e-03 5.290e+01  19.019  < 2e-16 ***
## indiv_1          2.243e-02  6.036e-03 1.447e+01   3.717  0.00219 ** 
## charity_1        8.832e-03  6.260e-03 1.669e+01   1.411  0.17667    
## need.c           1.425e-02  2.419e-03 7.463e+02   5.890 5.84e-09 ***
## diff.c           1.779e-02  1.942e-03 2.466e+02   9.161  < 2e-16 ***
## money.c          2.961e-01  1.456e-02 3.771e+02  20.345  < 2e-16 ***
## indiv_1:need.c   1.766e-02  2.164e-03 1.059e+03   8.160 9.42e-16 ***
## charity_1:need.c 1.714e-02  2.215e-03 1.114e+03   7.737 2.27e-14 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) indv_1 chrt_1 need.c diff.c mony.c in_1:.
## indiv_1     -0.446                                          
## charity_1   -0.471  0.808                                   
## need.c       0.524 -0.234 -0.297                            
## diff.c       0.107 -0.034 -0.030 -0.209                     
## money.c      0.686  0.143  0.109  0.353 -0.124              
## indv_1:nd.c -0.218  0.273  0.275 -0.675  0.015  0.008       
## chrty_1:nd. -0.221  0.281  0.232 -0.656  0.002  0.011  0.760
summary(m16 <- lmer(donate ~ (pract_1 + charity_1) * need.c + diff.c + money.c +
                      (pract_1 + charity_1 + diff.c + money.c + need.c | participant) + (1 | stimulus), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ (pract_1 + charity_1) * need.c + diff.c + money.c +  
##     (pract_1 + charity_1 + diff.c + money.c + need.c | participant) +  
##     (1 | stimulus)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -15690.3
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -7.5314 -0.3313 -0.0259  0.2600  7.8652 
## 
## Random effects:
##  Groups      Name        Variance  Std.Dev. Corr                         
##  participant (Intercept) 1.988e-02 0.140988                              
##              pract_1     4.128e-03 0.064249 -0.44                        
##              charity_1   2.520e-03 0.050204 -0.23  0.25                  
##              diff.c      7.480e-04 0.027350  0.05  0.08  0.02            
##              money.c     7.543e-02 0.274649  0.91 -0.28 -0.07 -0.17      
##              need.c      7.144e-04 0.026729  0.69 -0.09 -0.31 -0.15  0.65
##  stimulus    (Intercept) 1.291e-05 0.003592                              
##  Residual                8.419e-03 0.091753                              
## Number of obs: 9827, groups:  participant, 378; stimulus, 21
## 
## Fixed effects:
##                    Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)       1.767e-01  7.653e-03  3.489e+02  23.095  < 2e-16 ***
## pract_1          -2.243e-02  6.036e-03  1.447e+01  -3.717 0.002186 ** 
## charity_1        -1.360e-02  3.812e-03  6.273e+01  -3.568 0.000696 ***
## need.c            3.191e-02  1.861e-03  5.040e+02  17.143  < 2e-16 ***
## diff.c            1.779e-02  1.942e-03  2.466e+02   9.161  < 2e-16 ***
## money.c           2.961e-01  1.456e-02  3.771e+02  20.345  < 2e-16 ***
## pract_1:need.c   -1.766e-02  2.164e-03  1.059e+03  -8.160 9.42e-16 ***
## charity_1:need.c -5.205e-04  1.519e-03  2.965e+03  -0.343 0.731866    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) prct_1 chrt_1 need.c diff.c mony.c pr_1:.
## pract_1     -0.316                                          
## charity_1   -0.274  0.256                                   
## need.c       0.464 -0.013 -0.131                            
## diff.c       0.087  0.034  0.005 -0.255                     
## money.c      0.840 -0.143 -0.047  0.468 -0.124              
## prct_1:nd.c  0.016  0.273 -0.020 -0.285 -0.015 -0.008       
## chrty_1:nd.  0.005 -0.021 -0.121 -0.361 -0.018  0.004  0.317
tab_model(m15, m16)
  donate donate
Predictors Estimates CI p Estimates CI p
(Intercept) 0.15 0.14 – 0.17 <0.001 0.18 0.16 – 0.19 <0.001
indiv_1 0.02 0.01 – 0.03 <0.001
charity_1 0.01 -0.00 – 0.02 0.158 -0.01 -0.02 – -0.01 <0.001
need.c 0.01 0.01 – 0.02 <0.001 0.03 0.03 – 0.04 <0.001
diff.c 0.02 0.01 – 0.02 <0.001 0.02 0.01 – 0.02 <0.001
money.c 0.30 0.27 – 0.32 <0.001 0.30 0.27 – 0.32 <0.001
indiv_1 * need.c 0.02 0.01 – 0.02 <0.001
charity_1 * need.c 0.02 0.01 – 0.02 <0.001 -0.00 -0.00 – 0.00 0.732
pract_1 -0.02 -0.03 – -0.01 <0.001
pract_1 * need.c -0.02 -0.02 – -0.01 <0.001
Random Effects
σ2 0.01 0.01
τ00 0.02 participant 0.02 participant
0.00 stimulus 0.00 stimulus
τ11 0.00 participant.indiv_1 0.00 participant.pract_1
0.01 participant.charity_1 0.00 participant.charity_1
0.00 participant.diff.c 0.00 participant.diff.c
0.08 participant.money.c 0.08 participant.money.c
0.00 participant.need.c 0.00 participant.need.c
ρ01 -0.02 participant.indiv_1 -0.44 participant.pract_1
-0.11 participant.charity_1 -0.23 participant.charity_1
0.09 participant.diff.c 0.05 participant.diff.c
0.88 participant.money.c 0.91 participant.money.c
0.72 participant.need.c 0.69 participant.need.c
ICC 0.77 0.77
N 378 participant 378 participant
21 stimulus 21 stimulus
Observations 9827 9827
Marginal R2 / Conditional R2 0.251 / 0.831 0.251 / 0.831

b. proportion donated

summary(m17 <- lmer(propDonate ~ (indiv_1 + charity_1) * need.c + diff.c + money.c +
                      (indiv_1 + charity_1 + money.c + need.c + diff.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ (indiv_1 + charity_1) * need.c + diff.c + money.c +  
##     (indiv_1 + charity_1 + money.c + need.c + diff.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -8087.5
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -6.4031 -0.3154 -0.0271  0.2498  6.1310 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr                         
##  participant (Intercept) 0.052305 0.22870                               
##              indiv_1     0.015067 0.12275  -0.11                        
##              charity_1   0.019075 0.13811  -0.20  0.79                  
##              money.c     0.003852 0.06206  -0.23  0.08  0.09            
##              need.c      0.002655 0.05153   0.65  0.10 -0.08 -0.20      
##              diff.c      0.003284 0.05731   0.21 -0.08 -0.06 -0.48  0.01
##  Residual                0.017608 0.13270                               
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                    Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)       2.805e-01  1.297e-02  4.026e+02  21.625  < 2e-16 ***
## indiv_1           3.138e-02  8.332e-03  3.872e+02   3.766 0.000191 ***
## charity_1         6.490e-03  8.979e-03  4.003e+02   0.723 0.470244    
## need.c            3.199e-02  4.440e-03  9.741e+02   7.205 1.16e-12 ***
## diff.c            4.401e-02  3.804e-03  2.636e+02  11.570  < 2e-16 ***
## money.c          -7.499e-03  6.021e-03  3.766e+02  -1.245 0.213787    
## indiv_1:need.c    2.191e-02  3.685e-03  1.248e+03   5.945 3.58e-09 ***
## charity_1:need.c  2.223e-02  3.790e-03  1.414e+03   5.867 5.53e-09 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) indv_1 chrt_1 need.c diff.c mony.c in_1:.
## indiv_1     -0.284                                          
## charity_1   -0.337  0.795                                   
## need.c       0.562 -0.285 -0.343                            
## diff.c       0.194 -0.054 -0.046 -0.119                     
## money.c     -0.109  0.020  0.025 -0.085 -0.213              
## indv_1:nd.c -0.248  0.367  0.352 -0.679  0.012  0.035       
## chrty_1:nd. -0.250  0.376  0.314 -0.664  0.001  0.042  0.813
summary(m18 <- lmer(propDonate ~ (pract_1 + charity_1) * need.c + diff.c + money.c +
                      (pract_1 + charity_1 + money.c + need.c + diff.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ (pract_1 + charity_1) * need.c + diff.c + money.c +  
##     (pract_1 + charity_1 + money.c + need.c + diff.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -8087.5
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -6.4031 -0.3154 -0.0271  0.2498  6.1310 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr                         
##  participant (Intercept) 0.061299 0.24759                               
##              pract_1     0.015067 0.12275  -0.40                        
##              charity_1   0.007340 0.08567  -0.23  0.16                  
##              money.c     0.003852 0.06206  -0.18 -0.08  0.04            
##              need.c      0.002655 0.05153   0.65 -0.10 -0.27 -0.20      
##              diff.c      0.003284 0.05731   0.15  0.08  0.01 -0.48  0.01
##  Residual                0.017608 0.13270                               
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                    Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)       3.118e-01  1.327e-02  3.645e+02  23.495  < 2e-16 ***
## pract_1          -3.138e-02  8.332e-03  3.872e+02  -3.766 0.000191 ***
## charity_1        -2.489e-02  5.571e-03  3.786e+02  -4.467 1.05e-05 ***
## need.c            5.390e-02  3.330e-03  4.511e+02  16.187  < 2e-16 ***
## diff.c            4.401e-02  3.804e-03  2.636e+02  11.570  < 2e-16 ***
## money.c          -7.499e-03  6.021e-03  3.766e+02  -1.245 0.213787    
## pract_1:need.c   -2.191e-02  3.685e-03  1.248e+03  -5.945 3.58e-09 ***
## charity_1:need.c  3.227e-04  2.287e-03  3.472e+03   0.141 0.887806    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) prct_1 chrt_1 need.c diff.c mony.c pr_1:.
## pract_1     -0.350                                          
## charity_1   -0.248  0.214                                   
## need.c       0.481 -0.026 -0.150                            
## diff.c       0.156  0.054  0.006 -0.146                     
## money.c     -0.094 -0.020  0.010 -0.075 -0.213              
## prct_1:nd.c  0.011  0.367 -0.018 -0.202 -0.012 -0.035       
## chrty_1:nd.  0.005 -0.031 -0.122 -0.301 -0.017  0.014  0.264
tab_model(m17, m18)
  propDonate propDonate
Predictors Estimates CI p Estimates CI p
(Intercept) 0.28 0.26 – 0.31 <0.001 0.31 0.29 – 0.34 <0.001
indiv_1 0.03 0.02 – 0.05 <0.001
charity_1 0.01 -0.01 – 0.02 0.470 -0.02 -0.04 – -0.01 <0.001
need.c 0.03 0.02 – 0.04 <0.001 0.05 0.05 – 0.06 <0.001
diff.c 0.04 0.04 – 0.05 <0.001 0.04 0.04 – 0.05 <0.001
money.c -0.01 -0.02 – 0.00 0.213 -0.01 -0.02 – 0.00 0.213
indiv_1 * need.c 0.02 0.01 – 0.03 <0.001
charity_1 * need.c 0.02 0.01 – 0.03 <0.001 0.00 -0.00 – 0.00 0.888
pract_1 -0.03 -0.05 – -0.02 <0.001
pract_1 * need.c -0.02 -0.03 – -0.01 <0.001
Random Effects
σ2 0.02 0.02
τ00 0.05 participant 0.06 participant
τ11 0.02 participant.indiv_1 0.02 participant.pract_1
0.02 participant.charity_1 0.01 participant.charity_1
0.00 participant.money.c 0.00 participant.money.c
0.00 participant.need.c 0.00 participant.need.c
0.00 participant.diff.c 0.00 participant.diff.c
ρ01 -0.11 -0.40
-0.20 -0.23
-0.23 -0.18
0.65 0.65
0.21 0.15
ICC 0.82 0.82
N 378 participant 378 participant
Observations 9827 9827
Marginal R2 / Conditional R2 0.193 / 0.852 0.193 / 0.852

9. is there an interaction with condition and difference made while controlling money allocted and need

a. raw donated

summary(m15 <- lmer(donate ~ (indiv_1 + charity_1) * diff.c + money.c + need.c + 
                      (indiv_1 + charity_1 + diff.c + money.c + need.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ (indiv_1 + charity_1) * diff.c + money.c + need.c +  
##     (indiv_1 + charity_1 + diff.c + money.c + need.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -15668
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -7.5092 -0.3304 -0.0278  0.2521  7.8654 
## 
## Random effects:
##  Groups      Name        Variance  Std.Dev. Corr                         
##  participant (Intercept) 0.0159874 0.12644                               
##              indiv_1     0.0046685 0.06833  -0.03                        
##              charity_1   0.0052822 0.07268  -0.11  0.75                  
##              diff.c      0.0007301 0.02702   0.11 -0.08 -0.07            
##              money.c     0.0757557 0.27524   0.86  0.30  0.21 -0.16      
##              need.c      0.0007187 0.02681   0.72  0.08 -0.14 -0.13  0.63
##  Residual                0.0084124 0.09172                               
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                   Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)      1.634e-01  7.085e-03 3.683e+02  23.059  < 2e-16 ***
## indiv_1          1.393e-02  4.629e-03 3.435e+02   3.009  0.00282 ** 
## charity_1        3.023e-04  4.842e-03 3.531e+02   0.062  0.95026    
## diff.c           5.955e-03  2.563e-03 5.871e+02   2.323  0.02050 *  
## money.c          2.972e-01  1.459e-02 3.774e+02  20.372  < 2e-16 ***
## need.c           2.890e-02  1.711e-03 3.530e+02  16.894  < 2e-16 ***
## indiv_1:diff.c   1.429e-02  2.260e-03 1.010e+03   6.323 3.84e-10 ***
## charity_1:diff.c 1.525e-02  2.257e-03 1.038e+03   6.757 2.35e-11 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) indv_1 chrt_1 diff.c mony.c need.c in_1:.
## indiv_1     -0.209                                          
## charity_1   -0.260  0.737                                   
## diff.c       0.195 -0.173 -0.159                            
## money.c      0.773  0.212  0.154 -0.101                     
## need.c       0.576 -0.051 -0.197 -0.213  0.497              
## indv_1:dff. -0.133  0.189  0.188 -0.608  0.019 -0.008       
## chrty_1:df. -0.138  0.197  0.162 -0.622  0.020  0.011  0.758
summary(m16 <- lmer(donate ~ (pract_1 + charity_1) * diff.c + money.c + need.c + 
                      (pract_1 + charity_1 + diff.c + money.c + need.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: donate ~ (pract_1 + charity_1) * diff.c + money.c + need.c +  
##     (pract_1 + charity_1 + diff.c + money.c + need.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -15668
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -7.5092 -0.3304 -0.0278  0.2521  7.8654 
## 
## Random effects:
##  Groups      Name        Variance  Std.Dev. Corr                         
##  participant (Intercept) 0.0201179 0.14184                               
##              pract_1     0.0046685 0.06833  -0.45                        
##              charity_1   0.0025360 0.05036  -0.24  0.28                  
##              diff.c      0.0007301 0.02702   0.06  0.08  0.01            
##              money.c     0.0757561 0.27524   0.91 -0.30 -0.09 -0.16      
##              need.c      0.0007187 0.02681   0.68 -0.08 -0.31 -0.13  0.63
##  Residual                0.0084124 0.09172                               
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                    Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)       1.773e-01  7.610e-03  3.620e+02  23.300  < 2e-16 ***
## pract_1          -1.393e-02  4.629e-03  3.435e+02  -3.009  0.00282 ** 
## charity_1        -1.363e-02  3.441e-03  3.756e+02  -3.960 8.96e-05 ***
## diff.c            2.025e-02  2.151e-03  3.628e+02   9.411  < 2e-16 ***
## money.c           2.972e-01  1.459e-02  3.774e+02  20.372  < 2e-16 ***
## need.c            2.890e-02  1.711e-03  3.530e+02  16.894  < 2e-16 ***
## pract_1:diff.c   -1.429e-02  2.260e-03  1.010e+03  -6.323 3.84e-10 ***
## charity_1:diff.c  9.592e-04  1.571e-03  1.152e+03   0.611  0.54161    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) prct_1 chrt_1 diff.c mony.c need.c pr_1:.
## pract_1     -0.414                                          
## charity_1   -0.266  0.308                                   
## diff.c       0.082  0.008  0.022                            
## money.c      0.849 -0.212 -0.069 -0.101                     
## need.c       0.505  0.051 -0.208 -0.262  0.497              
## prct_1:dff.  0.009  0.189 -0.011 -0.326 -0.019  0.008       
## chrty_1:df.  0.000 -0.012 -0.070 -0.390  0.002  0.027  0.350
tab_model(m15, m16)
  donate donate
Predictors Estimates CI p Estimates CI p
(Intercept) 0.16 0.15 – 0.18 <0.001 0.18 0.16 – 0.19 <0.001
indiv_1 0.01 0.00 – 0.02 0.003
charity_1 0.00 -0.01 – 0.01 0.950 -0.01 -0.02 – -0.01 <0.001
diff.c 0.01 0.00 – 0.01 0.020 0.02 0.02 – 0.02 <0.001
money.c 0.30 0.27 – 0.33 <0.001 0.30 0.27 – 0.33 <0.001
need.c 0.03 0.03 – 0.03 <0.001 0.03 0.03 – 0.03 <0.001
indiv_1 * diff.c 0.01 0.01 – 0.02 <0.001
charity_1 * diff.c 0.02 0.01 – 0.02 <0.001 0.00 -0.00 – 0.00 0.541
pract_1 -0.01 -0.02 – -0.00 0.003
pract_1 * diff.c -0.01 -0.02 – -0.01 <0.001
Random Effects
σ2 0.01 0.01
τ00 0.02 participant 0.02 participant
τ11 0.00 participant.indiv_1 0.00 participant.pract_1
0.01 participant.charity_1 0.00 participant.charity_1
0.00 participant.diff.c 0.00 participant.diff.c
0.08 participant.money.c 0.08 participant.money.c
0.00 participant.need.c 0.00 participant.need.c
ρ01 -0.03 -0.45
-0.11 -0.24
0.11 0.06
0.86 0.91
0.72 0.68
ICC 0.77 0.77
N 378 participant 378 participant
Observations 9827 9827
Marginal R2 / Conditional R2 0.252 / 0.832 0.252 / 0.832

b. proportion donated

summary(m17 <- lmer(propDonate ~ (indiv_1 + charity_1) * diff.c + money.c + need.c + 
                      (indiv_1 + charity_1 + money.c + need.c + diff.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ (indiv_1 + charity_1) * diff.c + money.c + need.c +  
##     (indiv_1 + charity_1 + money.c + need.c + diff.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -8084.3
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -6.4088 -0.3146 -0.0271  0.2500  6.1087 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr                         
##  participant (Intercept) 0.051960 0.22795                               
##              indiv_1     0.016299 0.12767  -0.11                        
##              charity_1   0.019555 0.13984  -0.19  0.80                  
##              money.c     0.003897 0.06243  -0.22  0.04  0.06            
##              need.c      0.002654 0.05152   0.64  0.09 -0.08 -0.19      
##              diff.c      0.003241 0.05693   0.22 -0.08 -0.07 -0.48  0.02
##  Residual                0.017580 0.13259                               
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                    Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)       2.914e-01  1.260e-02  3.729e+02  23.123  < 2e-16 ***
## indiv_1           2.099e-02  8.053e-03  3.462e+02   2.606  0.00956 ** 
## charity_1        -3.695e-03  8.624e-03  3.597e+02  -0.429  0.66853    
## diff.c            2.706e-02  4.737e-03  5.746e+02   5.713 1.78e-08 ***
## money.c          -6.104e-03  6.043e-03  3.800e+02  -1.010  0.31309    
## need.c            5.117e-02  3.149e-03  3.618e+02  16.251  < 2e-16 ***
## indiv_1:diff.c    2.058e-02  3.715e-03  1.276e+03   5.538 3.71e-08 ***
## charity_1:diff.c  2.112e-02  3.781e-03  1.422e+03   5.586 2.79e-08 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) indv_1 chrt_1 diff.c mony.c need.c in_1:.
## indiv_1     -0.227                                          
## charity_1   -0.285  0.781                                   
## diff.c       0.251 -0.171 -0.156                            
## money.c     -0.105  0.008  0.014 -0.221                     
## need.c       0.542 -0.019 -0.142 -0.119 -0.079              
## indv_1:dff. -0.128  0.188  0.183 -0.561  0.075 -0.019       
## chrty_1:df. -0.132  0.198  0.165 -0.575  0.078 -0.005  0.792
summary(m18 <- lmer(propDonate ~ (pract_1 + charity_1) * diff.c + money.c + need.c + 
                      (pract_1 + charity_1 + money.c + need.c + diff.c | participant), 
                   control = lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000)), data = d))
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: propDonate ~ (pract_1 + charity_1) * diff.c + money.c + need.c +  
##     (pract_1 + charity_1 + money.c + need.c + diff.c | participant)
##    Data: d
## Control: lmerControl(optimizer = "bobyqa", optCtrl = list(maxfun = 10000))
## 
## REML criterion at convergence: -8084.3
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -6.4088 -0.3146 -0.0271  0.2500  6.1087 
## 
## Random effects:
##  Groups      Name        Variance Std.Dev. Corr                         
##  participant (Intercept) 0.061864 0.24872                               
##              pract_1     0.016299 0.12767  -0.41                        
##              charity_1   0.007372 0.08586  -0.23  0.19                  
##              money.c     0.003897 0.06243  -0.18 -0.04  0.03            
##              need.c      0.002654 0.05152   0.63 -0.09 -0.27 -0.19      
##              diff.c      0.003241 0.05693   0.16  0.08  0.00 -0.48  0.02
##  Residual                0.017580 0.13259                               
## Number of obs: 9827, groups:  participant, 378
## 
## Fixed effects:
##                    Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)       3.124e-01  1.333e-02  3.649e+02  23.438  < 2e-16 ***
## pract_1          -2.099e-02  8.053e-03  3.462e+02  -2.606  0.00956 ** 
## charity_1        -2.468e-02  5.548e-03  3.734e+02  -4.448 1.14e-05 ***
## diff.c            4.764e-02  4.063e-03  3.443e+02  11.725  < 2e-16 ***
## money.c          -6.104e-03  6.043e-03  3.800e+02  -1.010  0.31309    
## need.c            5.117e-02  3.149e-03  3.618e+02  16.251  < 2e-16 ***
## pract_1:diff.c   -2.058e-02  3.715e-03  1.276e+03  -5.538 3.71e-08 ***
## charity_1:diff.c  5.434e-04  2.419e-03  1.338e+03   0.225  0.82232    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) prct_1 chrt_1 diff.c mony.c need.c pr_1:.
## pract_1     -0.390                                          
## charity_1   -0.251  0.238                                   
## diff.c       0.150  0.027  0.018                            
## money.c     -0.095 -0.008  0.009 -0.189                     
## need.c       0.501  0.019 -0.192 -0.156 -0.079              
## prct_1:dff.  0.007  0.188 -0.012 -0.261 -0.075  0.019       
## chrty_1:df.  0.003 -0.021 -0.067 -0.317  0.008  0.021  0.298
tab_model(m17, m18)
  propDonate propDonate
Predictors Estimates CI p Estimates CI p
(Intercept) 0.29 0.27 – 0.32 <0.001 0.31 0.29 – 0.34 <0.001
indiv_1 0.02 0.01 – 0.04 0.009
charity_1 -0.00 -0.02 – 0.01 0.668 -0.02 -0.04 – -0.01 <0.001
diff.c 0.03 0.02 – 0.04 <0.001 0.05 0.04 – 0.06 <0.001
money.c -0.01 -0.02 – 0.01 0.312 -0.01 -0.02 – 0.01 0.312
need.c 0.05 0.05 – 0.06 <0.001 0.05 0.05 – 0.06 <0.001
indiv_1 * diff.c 0.02 0.01 – 0.03 <0.001
charity_1 * diff.c 0.02 0.01 – 0.03 <0.001 0.00 -0.00 – 0.01 0.822
pract_1 -0.02 -0.04 – -0.01 0.009
pract_1 * diff.c -0.02 -0.03 – -0.01 <0.001
Random Effects
σ2 0.02 0.02
τ00 0.05 participant 0.06 participant
τ11 0.02 participant.indiv_1 0.02 participant.pract_1
0.02 participant.charity_1 0.01 participant.charity_1
0.00 participant.money.c 0.00 participant.money.c
0.00 participant.need.c 0.00 participant.need.c
0.00 participant.diff.c 0.00 participant.diff.c
ρ01 -0.11 -0.41
-0.19 -0.23
-0.22 -0.18
0.64 0.63
0.22 0.16
ICC 0.82 0.82
N 378 participant 378 participant
Observations 9827 9827
Marginal R2 / Conditional R2 0.197 / 0.853 0.197 / 0.853