Function – Linear model

lm_results <- function(dv, iv) {
  
  #Constrastes para Anova
  #options("contrasts")
  options(contrasts = c("contr.helmert", "contr.poly")) #all the time we need this option
  #Do Regression analysis
  mod <- eval(substitute(lm(dv ~ iv +  ChildsAge + relevel(Condition,ref = 2), data = dataset)))
  #display results
  print(anova_stats(car::Anova(mod, type = 3)))
  
  #constrastes para regressao
  options(contrasts = c("contr.treatment", "contr.poly")) #all the time we need this option
  mod2 <- eval(substitute(lm(dv ~ iv +  ChildsAge + relevel(Condition,ref = 2), data = dataset)))

  #glance(mod2)
  summary(mod2)
}

Factor 1 - Child interest in literacy

##                          term sumsq meansq df statistic p.value etasq
## 1                 (Intercept) 0.735  0.735  1     2.524   0.136 0.078
## 2     child_interest_total_t1 3.843  3.843  1    13.200   0.003 0.407
## 3                   ChildsAge 0.024  0.024  1     0.081   0.781 0.002
## 4 relevel(Condition, ref = 2) 1.063  1.063  1     3.652   0.078 0.113
## 5                   Residuals 3.785  0.291 13        NA      NA    NA
##   partial.etasq omegasq partial.omegasq cohens.f power
## 1         0.163   0.046           0.078    0.441 0.353
## 2         0.504   0.365           0.404    1.008 0.950
## 3         0.006  -0.027          -0.054    0.079 0.059
## 4         0.219   0.079           0.128    0.530 0.476
## 5            NA      NA              NA       NA    NA
## 
## Call:
## lm(formula = child_interest_total_t2 ~ child_interest_total_t1 + 
##     ChildsAge + relevel(Condition, ref = 2), data = dataset)
## 
## Residuals:
##    Min     1Q Median     3Q    Max 
## -0.722 -0.413 -0.006  0.356  0.794 
## 
## Coefficients:
##                              Estimate Std. Error t value Pr(>|t|)   
## (Intercept)                   1.17119    0.89833    1.30    0.215   
## child_interest_total_t1       0.74720    0.20566    3.63    0.003 **
## ChildsAge                    -0.00786    0.02766   -0.28    0.781   
## relevel(Condition, ref = 2)1  0.51391    0.26891    1.91    0.078 . 
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.54 on 13 degrees of freedom
## Multiple R-squared:  0.604,  Adjusted R-squared:  0.513 
## F-statistic: 6.62 on 3 and 13 DF,  p-value: 0.00593
## Some items ( T1SingSongs T1ListenMusic ) were negatively correlated with the total scale and 
## probably should be reversed.  
## To do this, run the function again with the 'check.keys=TRUE' option
## 
## Reliability analysis   
## Call: alpha(x = .)
## 
##   raw_alpha std.alpha G6(smc) average_r S/N  ase mean   sd median_r
##       0.65      0.63    0.76      0.16 1.7 0.11  4.8 0.75     0.11
## 
##  lower alpha upper     95% confidence boundaries
## 0.44 0.65 0.85 
## 
##  Reliability if an item is dropped:
##                       raw_alpha std.alpha G6(smc) average_r S/N alpha se
## T1SingSongs                0.67      0.68    0.77      0.21 2.1    0.102
## T1IndependentColoring      0.59      0.52    0.64      0.12 1.1    0.122
## T1PretendWrite             0.60      0.52    0.68      0.12 1.1    0.118
## T1ListenMusic              0.68      0.69    0.77      0.22 2.3    0.098
## T1TellStory                0.54      0.55    0.66      0.13 1.2    0.146
## T1Lookmagazine             0.60      0.59    0.74      0.15 1.4    0.119
## T1LookNewspaper            0.63      0.61    0.76      0.17 1.6    0.104
## T1DoCard                   0.57      0.58    0.73      0.15 1.4    0.129
## T1IndependentBook          0.64      0.60    0.73      0.16 1.5    0.108
##                       var.r med.r
## T1SingSongs           0.069 0.216
## T1IndependentColoring 0.046 0.101
## T1PretendWrite        0.055 0.092
## T1ListenMusic         0.059 0.216
## T1TellStory           0.057 0.101
## T1Lookmagazine        0.078 0.101
## T1LookNewspaper       0.083 0.177
## T1DoCard              0.072 0.092
## T1IndependentBook     0.072 0.101
## 
##  Item statistics 
##                        n  raw.r std.r  r.cor r.drop mean   sd
## T1SingSongs           17  0.104  0.19  0.034 -0.014  6.5 0.80
## T1IndependentColoring 17  0.673  0.74  0.806  0.591  6.2 0.88
## T1PretendWrite        17  0.628  0.74  0.774  0.545  6.1 0.83
## T1ListenMusic         17 -0.089  0.11 -0.022 -0.180  6.5 0.62
## T1TellStory           17  0.786  0.67  0.685  0.574  4.4 2.37
## T1Lookmagazine        17  0.669  0.54  0.431  0.423  2.9 2.18
## T1LookNewspaper       17  0.473  0.46  0.320  0.272  1.8 1.51
## T1DoCard              17  0.685  0.58  0.498  0.490  2.2 1.86
## T1IndependentBook     17  0.362  0.49  0.414  0.253  6.4 0.80
## 
## Non missing response frequency for each item
##                          1    2    3    4    5    6    7 miss
## T1SingSongs           0.00 0.00 0.00 0.00 0.18 0.12 0.71    0
## T1IndependentColoring 0.00 0.00 0.00 0.06 0.12 0.41 0.41    0
## T1PretendWrite        0.00 0.00 0.00 0.06 0.12 0.53 0.29    0
## T1ListenMusic         0.00 0.00 0.00 0.00 0.06 0.41 0.53    0
## T1TellStory           0.29 0.00 0.00 0.06 0.12 0.41 0.12    0
## T1Lookmagazine        0.47 0.06 0.12 0.06 0.12 0.12 0.06    0
## T1LookNewspaper       0.65 0.18 0.06 0.00 0.06 0.06 0.00    0
## T1DoCard              0.59 0.12 0.00 0.18 0.06 0.00 0.06    0
## T1IndependentBook     0.00 0.00 0.00 0.06 0.00 0.41 0.53    0

Factor 2 - Adults value placed on literacy

##                          term sumsq meansq df statistic p.value etasq
## 1                 (Intercept)  1.55   1.55  1      1.97   0.184 0.094
## 2    adults_literacy_total_t1  3.44   3.44  1      4.35   0.057 0.209
## 3                   ChildsAge  0.36   0.36  1      0.45   0.514 0.022
## 4 relevel(Condition, ref = 2)  0.86   0.86  1      1.08   0.317 0.052
## 5                   Residuals 10.29   0.79 13        NA      NA    NA
##   partial.etasq omegasq partial.omegasq cohens.f power
## 1         0.131   0.044           0.051     0.39  0.29
## 2         0.251   0.153           0.157     0.58  0.54
## 3         0.033  -0.025          -0.032     0.19  0.10
## 4         0.077   0.004           0.005     0.29  0.18
## 5            NA      NA              NA       NA    NA
## 
## Call:
## lm(formula = adults_literacy_total_t2 ~ adults_literacy_total_t1 + 
##     ChildsAge + relevel(Condition, ref = 2), data = dataset)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -1.2520 -0.7447  0.0027  0.3269  2.0061 
## 
## Coefficients:
##                              Estimate Std. Error t value Pr(>|t|)  
## (Intercept)                    1.3998     1.2123    1.15    0.269  
## adults_literacy_total_t1       0.4530     0.2171    2.09    0.057 .
## ChildsAge                      0.0276     0.0412    0.67    0.514  
## relevel(Condition, ref = 2)1   0.5053     0.4855    1.04    0.317  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.89 on 13 degrees of freedom
## Multiple R-squared:  0.316,  Adjusted R-squared:  0.158 
## F-statistic:    2 on 3 and 13 DF,  p-value: 0.164
## 
## Reliability analysis   
## Call: alpha(x = ., check.keys = T)
## 
##   raw_alpha std.alpha G6(smc) average_r S/N  ase mean  sd median_r
##       0.82      0.82    0.95      0.28 4.6 0.06  3.8 1.2     0.27
## 
##  lower alpha upper     95% confidence boundaries
## 0.71 0.82 0.94 
## 
##  Reliability if an item is dropped:
##                     raw_alpha std.alpha G6(smc) average_r S/N alpha se
## SendTextMsg              0.82      0.82    0.95      0.29 4.5    0.062
## WriteEmails              0.80      0.80    0.94      0.27 4.0    0.068
## ReadOnline               0.82      0.82    0.94      0.29 4.4    0.063
## LeaveWrittenMessage      0.80      0.80    0.91      0.27 4.0    0.068
## ToBuyOrDoList            0.79      0.79    0.93      0.26 3.8    0.071
## ReadMagazine             0.82      0.82    0.94      0.29 4.5    0.060
## ReadNewspaper            0.82      0.81    0.92      0.28 4.2    0.063
## ReadBookNovel-           0.85      0.84    0.94      0.33 5.4    0.054
## UseDictionary            0.81      0.81    0.93      0.28 4.2    0.063
## ReadAdvertisements       0.80      0.80    0.92      0.26 3.9    0.070
## UseCookBook              0.79      0.79    0.94      0.25 3.7    0.074
## ReadBible                0.80      0.80    0.91      0.26 3.9    0.069
##                     var.r med.r
## SendTextMsg         0.057  0.28
## WriteEmails         0.055  0.27
## ReadOnline          0.058  0.31
## LeaveWrittenMessage 0.048  0.26
## ToBuyOrDoList       0.056  0.24
## ReadMagazine        0.049  0.29
## ReadNewspaper       0.048  0.29
## ReadBookNovel-      0.036  0.31
## UseDictionary       0.049  0.27
## ReadAdvertisements  0.054  0.26
## UseCookBook         0.047  0.26
## ReadBible           0.051  0.27
## 
##  Item statistics 
##                      n raw.r std.r r.cor r.drop mean  sd
## SendTextMsg         17  0.46  0.47  0.40  0.364  5.7 1.8
## WriteEmails         16  0.68  0.65  0.62  0.560  3.9 2.5
## ReadOnline          17  0.52  0.51  0.48  0.404  6.1 1.7
## LeaveWrittenMessage 17  0.66  0.66  0.66  0.575  2.8 1.8
## ToBuyOrDoList       17  0.74  0.73  0.71  0.662  4.1 2.3
## ReadMagazine        17  0.43  0.48  0.46  0.326  2.8 1.7
## ReadNewspaper       16  0.51  0.58  0.58  0.428  2.3 1.7
## ReadBookNovel-      17  0.18  0.16  0.12  0.039  3.6 2.0
## UseDictionary       17  0.53  0.58  0.57  0.443  2.3 1.5
## ReadAdvertisements  17  0.72  0.69  0.69  0.622  4.4 2.2
## UseCookBook         17  0.79  0.77  0.76  0.718  3.8 2.2
## ReadBible           16  0.76  0.70  0.71  0.622  3.3 1.9
## 
## Non missing response frequency for each item
##                        1    2    3    4    5    6    7 miss
## SendTextMsg         0.06 0.00 0.06 0.12 0.12 0.12 0.53 0.00
## WriteEmails         0.25 0.19 0.06 0.06 0.00 0.19 0.25 0.06
## ReadOnline          0.06 0.00 0.06 0.00 0.00 0.29 0.59 0.00
## LeaveWrittenMessage 0.35 0.06 0.35 0.06 0.06 0.06 0.06 0.00
## ToBuyOrDoList       0.29 0.00 0.06 0.18 0.06 0.29 0.12 0.00
## ReadMagazine        0.35 0.18 0.06 0.24 0.12 0.06 0.00 0.00
## ReadNewspaper       0.56 0.06 0.00 0.25 0.12 0.00 0.00 0.06
## ReadBookNovel       0.06 0.24 0.12 0.06 0.00 0.47 0.06 0.00
## UseDictionary       0.41 0.24 0.18 0.06 0.06 0.06 0.00 0.00
## ReadAdvertisements  0.24 0.00 0.06 0.18 0.12 0.24 0.18 0.00
## UseCookBook         0.29 0.06 0.00 0.24 0.18 0.12 0.12 0.00
## ReadBible           0.25 0.19 0.00 0.31 0.06 0.19 0.00 0.06

Factor 3 - Press for achievement

##                          term  sumsq meansq df statistic p.value etasq
## 1                 (Intercept)  3.683  3.683  1     5.249   0.039 0.131
## 2  press4achievement_total_t1 14.069 14.069  1    20.052   0.001 0.502
## 3                   ChildsAge  1.178  1.178  1     1.679   0.218 0.042
## 4 relevel(Condition, ref = 2)  0.002  0.002  1     0.002   0.964 0.000
## 5                   Residuals  9.121  0.702 13        NA      NA    NA
##   partial.etasq omegasq partial.omegasq cohens.f power
## 1          0.29   0.104           0.191    0.635  0.62
## 2          0.61   0.465           0.514    1.242  0.99
## 3          0.11   0.017           0.036    0.359  0.25
## 4          0.00  -0.024          -0.059    0.013  0.05
## 5            NA      NA              NA       NA    NA
## 
## Call:
## lm(formula = press4achievement_total_t2 ~ press4achievement_total_t1 + 
##     ChildsAge + relevel(Condition, ref = 2), data = dataset)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -1.5473 -0.3785  0.0877  0.6129  1.0905 
## 
## Coefficients:
##                              Estimate Std. Error t value Pr(>|t|)    
## (Intercept)                    2.4034     1.0325    2.33  0.03672 *  
## press4achievement_total_t1     0.8448     0.1887    4.48  0.00062 ***
## ChildsAge                     -0.0546     0.0421   -1.30  0.21764    
## relevel(Condition, ref = 2)1  -0.0195     0.4177   -0.05  0.96351    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.84 on 13 degrees of freedom
## Multiple R-squared:  0.615,  Adjusted R-squared:  0.527 
## F-statistic: 6.93 on 3 and 13 DF,  p-value: 0.00498
## 
## Reliability analysis   
## Call: alpha(x = .)
## 
##   raw_alpha std.alpha G6(smc) average_r S/N   ase mean  sd median_r
##       0.76      0.76    0.83      0.34 3.1 0.089  4.6 1.2     0.38
## 
##  lower alpha upper     95% confidence boundaries
## 0.59 0.76 0.93 
## 
##  Reliability if an item is dropped:
##                     raw_alpha std.alpha G6(smc) average_r S/N alpha se
## TalkSoundsLetters        0.75      0.74    0.81      0.36 2.8    0.089
## TalkAlphabet             0.75      0.75    0.82      0.38 3.0    0.096
## ReadSignboardWChild      0.64      0.64    0.72      0.26 1.8    0.141
## HelpChildWrite           0.66      0.67    0.72      0.29 2.0    0.126
## PrintedInstructGame      0.78      0.78    0.81      0.41 3.5    0.083
## TakeChildLibrary         0.73      0.72    0.81      0.34 2.6    0.099
##                     var.r med.r
## TalkSoundsLetters   0.067  0.40
## TalkAlphabet        0.079  0.41
## ReadSignboardWChild 0.063  0.32
## HelpChildWrite      0.056  0.38
## PrintedInstructGame 0.029  0.38
## TakeChildLibrary    0.073  0.37
## 
##  Item statistics 
##                      n raw.r std.r r.cor r.drop mean  sd
## TalkSoundsLetters   17  0.63  0.62  0.52   0.41  4.6 2.1
## TalkAlphabet        17  0.52  0.58  0.47   0.38  5.8 1.2
## ReadSignboardWChild 17  0.88  0.87  0.88   0.78  4.6 2.1
## HelpChildWrite      17  0.82  0.80  0.81   0.71  4.5 2.0
## PrintedInstructGame 16  0.50  0.50  0.42   0.29  5.4 1.9
## TakeChildLibrary    17  0.66  0.66  0.56   0.48  2.8 1.8
## 
## Non missing response frequency for each item
##                        1    2    3    4    5    6    7 miss
## TalkSoundsLetters   0.18 0.00 0.06 0.18 0.12 0.29 0.18 0.00
## TalkAlphabet        0.00 0.00 0.06 0.12 0.12 0.35 0.35 0.00
## ReadSignboardWChild 0.12 0.12 0.06 0.06 0.24 0.24 0.18 0.00
## HelpChildWrite      0.18 0.00 0.06 0.18 0.24 0.24 0.12 0.00
## PrintedInstructGame 0.06 0.06 0.06 0.00 0.12 0.38 0.31 0.06
## TakeChildLibrary    0.35 0.18 0.12 0.18 0.06 0.12 0.00 0.00

Factor 4 - Attitude toward reading

##                          term sumsq meansq df statistic p.value etasq
## 1                 (Intercept) 0.001  0.001  1     0.011    0.92 0.000
## 2         attitude_factor1_t1 4.973  4.973  1    58.700    0.00 0.787
## 3                   ChildsAge 0.002  0.002  1     0.020    0.89 0.000
## 4 relevel(Condition, ref = 2) 0.242  0.242  1     2.856    0.12 0.038
## 5                   Residuals 1.101  0.085 13        NA      NA    NA
##   partial.etasq omegasq partial.omegasq cohens.f power
## 1         0.001  -0.013          -0.058    0.029 0.051
## 2         0.819   0.763           0.762    2.125 1.000
## 3         0.001  -0.013          -0.058    0.039 0.052
## 4         0.180   0.025           0.093    0.469 0.390
## 5            NA      NA              NA       NA    NA
## 
## Call:
## lm(formula = attitude_factor1_t2 ~ attitude_factor1_t1 + ChildsAge + 
##     relevel(Condition, ref = 2), data = dataset)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -0.3631 -0.2117 -0.0473  0.1772  0.5009 
## 
## Coefficients:
##                              Estimate Std. Error t value Pr(>|t|)    
## (Intercept)                   0.16258    0.37141    0.44     0.67    
## attitude_factor1_t1           0.86462    0.11285    7.66  3.6e-06 ***
## ChildsAge                     0.00184    0.01316    0.14     0.89    
## relevel(Condition, ref = 2)1 -0.24856    0.14708   -1.69     0.11    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.29 on 13 degrees of freedom
## Multiple R-squared:  0.841,  Adjusted R-squared:  0.805 
## F-statistic:   23 on 3 and 13 DF,  p-value: 0.0000179
##                          term sumsq meansq df statistic p.value etasq
## 1                 (Intercept) 3.559  3.559  1      64.6   0.000 0.744
## 2         attitude_factor2_t1 0.049  0.049  1       0.9   0.361 0.010
## 3                   ChildsAge 0.082  0.082  1       1.5   0.243 0.017
## 4 relevel(Condition, ref = 2) 0.378  0.378  1       6.9   0.021 0.079
## 5                   Residuals 0.716  0.055 13        NA      NA    NA
##   partial.etasq omegasq partial.omegasq cohens.f power
## 1         0.833   0.724           0.779     2.23  1.00
## 2         0.065  -0.001          -0.006     0.26  0.16
## 3         0.103   0.006           0.027     0.34  0.23
## 4         0.345   0.067           0.246     0.73  0.74
## 5            NA      NA              NA       NA    NA
## 
## Call:
## lm(formula = attitude_factor2_t2 ~ attitude_factor2_t1 + ChildsAge + 
##     relevel(Condition, ref = 2), data = dataset)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -0.5826 -0.0833  0.0328  0.1412  0.2644 
## 
## Coefficients:
##                              Estimate Std. Error t value Pr(>|t|)    
## (Intercept)                    2.7286     0.3529    7.73  3.2e-06 ***
## attitude_factor2_t1            0.1034     0.1092    0.95    0.361    
## ChildsAge                      0.0142     0.0116    1.22    0.243    
## relevel(Condition, ref = 2)1   0.3052     0.1165    2.62    0.021 *  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.23 on 13 degrees of freedom
## Multiple R-squared:  0.509,  Adjusted R-squared:  0.396 
## F-statistic:  4.5 on 3 and 13 DF,  p-value: 0.0225
##                          term sumsq meansq df statistic p.value etasq
## 1                 (Intercept) 0.077  0.077  1     1.078   0.318 0.035
## 2           attitude_total_t1 1.179  1.179  1    16.440   0.001 0.533
## 3                   ChildsAge 0.022  0.022  1     0.305   0.590 0.010
## 4 relevel(Condition, ref = 2) 0.003  0.003  1     0.036   0.852 0.001
## 5                   Residuals 0.932  0.072 13        NA      NA    NA
##   partial.etasq omegasq partial.omegasq cohens.f power
## 1         0.077   0.002           0.004    0.288 0.179
## 2         0.558   0.485           0.462    1.125 0.980
## 3         0.023  -0.022          -0.040    0.153 0.085
## 4         0.003  -0.030          -0.057    0.053 0.054
## 5            NA      NA              NA       NA    NA
## 
## Call:
## lm(formula = attitude_total_t2 ~ attitude_total_t1 + ChildsAge + 
##     relevel(Condition, ref = 2), data = dataset)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -0.3478 -0.1609 -0.0405  0.1177  0.5234 
## 
## Coefficients:
##                              Estimate Std. Error t value Pr(>|t|)   
## (Intercept)                   0.51004    0.48798    1.05   0.3150   
## attitude_total_t1             0.87143    0.21492    4.05   0.0014 **
## ChildsAge                    -0.00729    0.01321   -0.55   0.5902   
## relevel(Condition, ref = 2)1 -0.02614    0.13750   -0.19   0.8522   
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.27 on 13 degrees of freedom
## Multiple R-squared:  0.594,  Adjusted R-squared:  0.501 
## F-statistic: 6.35 on 3 and 13 DF,  p-value: 0.00695
## 
## Reliability analysis   
## Call: alpha(x = ., check.keys = TRUE)
## 
##   raw_alpha std.alpha G6(smc) average_r S/N  ase mean   sd median_r
##       0.86      0.86       1      0.33 6.4 0.05  1.7 0.56     0.34
## 
##  lower alpha upper     95% confidence boundaries
## 0.76 0.86 0.96 
## 
##  Reliability if an item is dropped:
##                                        raw_alpha std.alpha G6(smc)
## CantReadChildNoSpaceT1                      0.84      0.84       1
## DontHaveMatT1                               0.85      0.85       1
## CantReadChildMoreImportantThingsToDoT1      0.83      0.84       1
## CantReadChildMovesTooMuchT1                 0.86      0.86       1
## DifficultBoringReadChildT1                  0.85      0.86       1
## DisciplineWhenReadingt1                     0.84      0.84       1
## TooBusyTiredReadChildT1                     0.84      0.84       1
## CannotReadSoCantReadChildT1                 0.85      0.85       1
## WantChildValueBookst1-                      0.86      0.87       1
## ChildLikesToBeReadT1-                       0.86      0.86       1
## FeelCloseWhenReadingT1-                     0.86      0.87       1
## TryToBeEnthusiasticWReadT1-                 0.84      0.85       1
## ReadWhenChildWantsT1-                       0.87      0.87       1
##                                        average_r S/N alpha se var.r med.r
## CantReadChildNoSpaceT1                      0.31 5.3    0.058 0.061  0.31
## DontHaveMatT1                               0.32 5.7    0.056 0.068  0.31
## CantReadChildMoreImportantThingsToDoT1      0.30 5.2    0.060 0.065  0.29
## CantReadChildMovesTooMuchT1                 0.34 6.2    0.051 0.068  0.35
## DifficultBoringReadChildT1                  0.33 6.0    0.053 0.060  0.35
## DisciplineWhenReadingt1                     0.31 5.3    0.059 0.069  0.29
## TooBusyTiredReadChildT1                     0.31 5.4    0.058 0.071  0.29
## CannotReadSoCantReadChildT1                 0.33 5.9    0.054 0.069  0.35
## WantChildValueBookst1-                      0.35 6.5    0.049 0.071  0.36
## ChildLikesToBeReadT1-                       0.35 6.3    0.051 0.067  0.36
## FeelCloseWhenReadingT1-                     0.35 6.4    0.051 0.066  0.35
## TryToBeEnthusiasticWReadT1-                 0.32 5.7    0.056 0.074  0.31
## ReadWhenChildWantsT1-                       0.36 6.8    0.047 0.063  0.36
## 
##  Item statistics 
##                                         n raw.r std.r r.cor r.drop mean
## CantReadChildNoSpaceT1                 16  0.81  0.80  0.80   0.73  1.7
## DontHaveMatT1                          17  0.67  0.69  0.69   0.60  1.6
## CantReadChildMoreImportantThingsToDoT1 17  0.83  0.83  0.83   0.76  1.8
## CantReadChildMovesTooMuchT1            16  0.53  0.53  0.53   0.43  1.9
## DifficultBoringReadChildT1             16  0.53  0.58  0.58   0.49  1.4
## DisciplineWhenReadingt1                16  0.79  0.79  0.79   0.76  1.8
## TooBusyTiredReadChildT1                16  0.76  0.76  0.76   0.71  2.2
## CannotReadSoCantReadChildT1            17  0.59  0.62  0.62   0.52  1.5
## WantChildValueBookst1-                 17  0.46  0.44  0.44   0.34  1.7
## ChildLikesToBeReadT1-                  17  0.49  0.48  0.48   0.39  1.7
## FeelCloseWhenReadingT1-                17  0.47  0.45  0.45   0.37  1.5
## TryToBeEnthusiasticWReadT1-            17  0.71  0.69  0.69   0.62  1.8
## ReadWhenChildWantsT1-                  17  0.34  0.36  0.36   0.22  2.0
##                                          sd
## CantReadChildNoSpaceT1                 0.87
## DontHaveMatT1                          1.00
## CantReadChildMoreImportantThingsToDoT1 1.01
## CantReadChildMovesTooMuchT1            1.06
## DifficultBoringReadChildT1             0.62
## DisciplineWhenReadingt1                0.86
## TooBusyTiredReadChildT1                0.86
## CannotReadSoCantReadChildT1            0.87
## WantChildValueBookst1-                 1.05
## ChildLikesToBeReadT1-                  0.85
## FeelCloseWhenReadingT1-                0.80
## TryToBeEnthusiasticWReadT1-            1.03
## ReadWhenChildWantsT1-                  1.00
## 
## Non missing response frequency for each item
##                                           1    2    3    4 miss
## CantReadChildNoSpaceT1                 0.50 0.38 0.06 0.06 0.06
## DontHaveMatT1                          0.65 0.24 0.00 0.12 0.00
## CantReadChildMoreImportantThingsToDoT1 0.47 0.35 0.06 0.12 0.00
## CantReadChildMovesTooMuchT1            0.44 0.31 0.12 0.12 0.06
## DifficultBoringReadChildT1             0.69 0.25 0.06 0.00 0.06
## DisciplineWhenReadingt1                0.50 0.25 0.25 0.00 0.06
## TooBusyTiredReadChildT1                0.19 0.44 0.31 0.06 0.06
## CannotReadSoCantReadChildT1            0.65 0.24 0.06 0.06 0.00
## WantChildValueBookst1                  0.12 0.06 0.24 0.59 0.00
## ChildLikesToBeReadT1                   0.06 0.06 0.41 0.47 0.00
## FeelCloseWhenReadingT1                 0.06 0.00 0.35 0.59 0.00
## TryToBeEnthusiasticWReadT1             0.12 0.06 0.29 0.53 0.00
## ReadWhenChildWantsT1                   0.12 0.12 0.41 0.35 0.00

## geom_errorbar: na.rm = FALSE
## stat_summary: na.rm = FALSE, fun.data = function (x, mult = 1) 
## {
##     x <- stats::na.omit(x)
##     se <- mult * sqrt(stats::var(x)/length(x))
##     mean <- mean(x)
##     data.frame(y = mean, ymin = mean - se, ymax = mean + se)
## }
## position_identity
## geom_errorbar: na.rm = FALSE, width = 0.2
## stat_summary: fun.data = function (x, ...) 
## {
##     if (!requireNamespace("Hmisc", quietly = TRUE)) 
##         stop("Hmisc package required for this function", call. = FALSE)
##     fun <- getExportedValue("Hmisc", fun)
##     result <- do.call(fun, list(x = quote(x), ...))
##     plyr::rename(data.frame(t(result)), c(Median = "y", Mean = "y", Lower = "ymin", Upper = "ymax"), warn_missing = FALSE)
## }, fun.y = NULL, fun.ymax = NULL, fun.ymin = NULL, fun.args = list(), na.rm = FALSE
## position_identity

Factor 5 - Availability

##                          term  sumsq meansq df statistic p.value etasq
## 1                 (Intercept)  0.063  0.063  1     0.074    0.79 0.002
## 2             availability_t1 22.359 22.359  1    26.379    0.00 0.662
## 3                   ChildsAge  0.238  0.238  1     0.281    0.60 0.007
## 4 relevel(Condition, ref = 2)  0.077  0.077  1     0.091    0.77 0.002
## 5                   Residuals 11.019  0.848 13        NA      NA    NA
##   partial.etasq omegasq partial.omegasq cohens.f power
## 1         0.006  -0.023          -0.054    0.076 0.059
## 2         0.670   0.622           0.585    1.424 0.999
## 3         0.021  -0.018          -0.042    0.147 0.083
## 4         0.007  -0.022          -0.053    0.084 0.060
## 5            NA      NA              NA       NA    NA
## 
## Call:
## lm(formula = availability_t2 ~ availability_t1 + ChildsAge + 
##     relevel(Condition, ref = 2), data = dataset)
## 
## Residuals:
##    Min     1Q Median     3Q    Max 
## -1.470 -0.482 -0.213  0.886  1.225 
## 
## Coefficients:
##                              Estimate Std. Error t value Pr(>|t|)    
## (Intercept)                   -0.2245     1.0505   -0.21  0.83410    
## availability_t1                1.1600     0.2259    5.14  0.00019 ***
## ChildsAge                      0.0231     0.0435    0.53  0.60478    
## relevel(Condition, ref = 2)1  -0.1433     0.4746   -0.30  0.76752    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.92 on 13 degrees of freedom
## Multiple R-squared:  0.723,  Adjusted R-squared:  0.659 
## F-statistic: 11.3 on 3 and 13 DF,  p-value: 0.000631
## 
## Reliability analysis   
## Call: alpha(x = .)
## 
##   raw_alpha std.alpha G6(smc) average_r   S/N  ase mean  sd median_r
##       0.02     0.022   0.011     0.011 0.022 0.44  2.4 1.1    0.011
## 
##  lower alpha upper     95% confidence boundaries
## -0.84 0.02 0.88 
## 
##  Reliability if an item is dropped:
##                       raw_alpha std.alpha G6(smc) average_r S/N alpha se
## AdultsBooksAtHomeT1     0.01100     0.011 0.00012     0.011  NA       NA
## HowManyBooksChildHave   0.00012     0.011      NA        NA  NA       NA
##                         var.r med.r
## AdultsBooksAtHomeT1   0.01100 0.011
## HowManyBooksChildHave 0.00012 0.011
## 
##  Item statistics 
##                        n raw.r std.r r.cor r.drop mean  sd
## AdultsBooksAtHomeT1   17  0.56  0.71 0.075  0.011  2.2 1.3
## HowManyBooksChildHave 17  0.83  0.71 0.075  0.011  2.6 1.9
## 
## Non missing response frequency for each item
##                          1    2    3    4    5    6    7 miss
## AdultsBooksAtHomeT1   0.24 0.53 0.12 0.06 0.00 0.06 0.00    0
## HowManyBooksChildHave 0.35 0.24 0.18 0.06 0.06 0.06 0.06    0

Factor 6 - Reading

##                          term sumsq meansq df statistic p.value etasq
## 1                 (Intercept)  1.72   1.72  1       3.5   0.084 0.076
## 2                  reading_t1 13.76  13.76  1      28.0   0.000 0.613
## 3                   ChildsAge  0.00   0.00  1       0.0   0.996 0.000
## 4 relevel(Condition, ref = 2)  0.58   0.58  1       1.2   0.296 0.026
## 5                   Residuals  6.38   0.49 13        NA      NA    NA
##   partial.etasq omegasq partial.omegasq cohens.f power
## 1         0.212   0.053           0.122    0.519  0.46
## 2         0.683   0.579           0.600    1.469  1.00
## 3         0.000  -0.021          -0.059    0.002  0.05
## 4         0.084   0.004           0.010    0.302  0.19
## 5            NA      NA              NA       NA    NA
## 
## Call:
## lm(formula = reading_t2 ~ reading_t1 + ChildsAge + relevel(Condition, 
##     ref = 2), data = dataset)
## 
## Residuals:
##    Min     1Q Median     3Q    Max 
## -1.335 -0.401  0.353  0.424  0.653 
## 
## Coefficients:
##                               Estimate Std. Error t value Pr(>|t|)    
## (Intercept)                   1.844931   1.094667    1.69  0.11575    
## reading_t1                    0.622474   0.117555    5.30  0.00015 ***
## ChildsAge                    -0.000182   0.031733   -0.01  0.99551    
## relevel(Condition, ref = 2)1  0.383572   0.352080    1.09  0.29574    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.7 on 13 degrees of freedom
## Multiple R-squared:  0.687,  Adjusted R-squared:  0.615 
## F-statistic: 9.51 on 3 and 13 DF,  p-value: 0.00137
## 
## Reliability analysis   
## Call: alpha(x = .)
## 
##   raw_alpha std.alpha G6(smc) average_r S/N  ase mean  sd median_r
##       0.66      0.68    0.52      0.52 2.2 0.15  5.4 1.5     0.52
## 
##  lower alpha upper     95% confidence boundaries
## 0.36 0.66 0.97 
## 
##  Reliability if an item is dropped:
##              raw_alpha std.alpha G6(smc) average_r S/N alpha se var.r
## MomReadChild      0.52      0.52    0.27      0.52  NA       NA  0.52
## DadReadChild      0.27      0.52      NA        NA  NA       NA  0.27
##              med.r
## MomReadChild  0.52
## DadReadChild  0.52
## 
##  Item statistics 
##               n raw.r std.r r.cor r.drop mean  sd
## MomReadChild 17  0.83  0.87  0.63   0.52  6.1 1.5
## DadReadChild 17  0.91  0.87  0.63   0.52  4.6 2.0
## 
## Non missing response frequency for each item
##                 1    3    4    5    6    7 miss
## MomReadChild 0.06 0.00 0.00 0.12 0.29 0.53    0
## DadReadChild 0.18 0.06 0.06 0.41 0.12 0.18    0

Function for Correlations

corstars <- function(x, method=c("pearson", "spearman"), removeTriangle=c("upper", "lower"),
                     result=c("none", "html", "latex")) {
    #Compute correlation matrix
    require(Hmisc)
    library(xtable)
    x <- as.matrix(x)
    correlation_matrix<-rcorr(x, type=method[1])
    R <- correlation_matrix$r # Matrix of correlation coeficients
    p <- correlation_matrix$P # Matrix of p-value 
    
    ## Define notions for significance levels; spacing is important.
    mystars <- ifelse(p < .0001, "****", ifelse(p < .001, "*** ", ifelse(p < .01, "**  ", ifelse(p < .05, "*   ", "    "))))
    
    ## trunctuate the correlation matrix to two decimal
    R <- format(round(cbind(rep(-1.11, ncol(x)), R), 2))[,-1]
    
    ## build a new matrix that includes the correlations with their apropriate stars
    Rnew <- matrix(paste(R, mystars, sep=""), ncol=ncol(x))
  
    diag(Rnew) <- paste(diag(R), " ", sep="")
    rownames(Rnew) <- colnames(x)
    colnames(Rnew) <- paste(colnames(x), "", sep="")
    
    ## remove upper triangle of correlation matrix
    if(removeTriangle[1]=="upper"){
      Rnew <- as.matrix(Rnew)
      Rnew[upper.tri(Rnew, diag = TRUE)] <- ""
      Rnew <- as.data.frame(Rnew)
    }
    
    ## remove lower triangle of correlation matrix
    else if(removeTriangle[1]=="lower"){
      Rnew <- as.matrix(Rnew)
      Rnew[lower.tri(Rnew, diag = TRUE)] <- ""
      Rnew <- as.data.frame(Rnew)
    }
    
    ## remove last column and return the correlation matrix
    Rnew <- cbind(Rnew[1:length(Rnew)-1])
    if (result[1]=="none") return(Rnew)
    else{
      if(result[1]=="html") print(xtable(Rnew), type="html")
      else print(xtable(Rnew), type="latex") 
    }
}

Bivariate correlation

The previous results was:

##                            ValueLiteracyMSt1 PressAchievMSt1wLIB
## ValueLiteracyMSt1                                               
## PressAchievMSt1wLIB                 0.03                        
## AvailabilityBooksMSt1               0.27                0.40    
## BookReadingWChildMOMDADSt1          0.30                0.47    
## AttitudeScaleMSt1                   0.55*               0.10    
## TOTALACIRICHILDT1                  -0.31                0.22    
## TOTALACIRIADULTT1                   0.01               -0.01    
##                            AvailabilityBooksMSt1
## ValueLiteracyMSt1                               
## PressAchievMSt1wLIB                             
## AvailabilityBooksMSt1                           
## BookReadingWChildMOMDADSt1              0.36    
## AttitudeScaleMSt1                       0.19    
## TOTALACIRICHILDT1                      -0.01    
## TOTALACIRIADULTT1                       0.25    
##                            BookReadingWChildMOMDADSt1 AttitudeScaleMSt1
## ValueLiteracyMSt1                                                      
## PressAchievMSt1wLIB                                                    
## AvailabilityBooksMSt1                                                  
## BookReadingWChildMOMDADSt1                                             
## AttitudeScaleMSt1                            0.02                      
## TOTALACIRICHILDT1                           -0.03             -0.16    
## TOTALACIRIADULTT1                            0.08              0.01    
##                            TOTALACIRICHILDT1
## ValueLiteracyMSt1                           
## PressAchievMSt1wLIB                         
## AvailabilityBooksMSt1                       
## BookReadingWChildMOMDADSt1                  
## AttitudeScaleMSt1                           
## TOTALACIRICHILDT1                           
## TOTALACIRIADULTT1                   0.62**

And the present result is:

##                            child_interest_total_t1
## child_interest_total_t1                           
## adults_literacy_total_t1                  0.17    
## press4achievement_total_t1                0.63**  
## availability_t1                           0.38    
## reading_t1                                0.42    
## attitude_total_t1                         0.26    
## TOTALACIRICHILDT1                         0.02    
## TOTALACIRIADULTT1                        -0.24    
##                            adults_literacy_total_t1
## child_interest_total_t1                            
## adults_literacy_total_t1                           
## press4achievement_total_t1                 0.03    
## availability_t1                            0.25    
## reading_t1                                 0.31    
## attitude_total_t1                         -0.11    
## TOTALACIRICHILDT1                         -0.32    
## TOTALACIRIADULTT1                          0.00    
##                            press4achievement_total_t1 availability_t1
## child_interest_total_t1                                              
## adults_literacy_total_t1                                             
## press4achievement_total_t1                                           
## availability_t1                              0.43                    
## reading_t1                                   0.50*           0.36    
## attitude_total_t1                            0.23           -0.12    
## TOTALACIRICHILDT1                            0.26            0.01    
## TOTALACIRIADULTT1                            0.00            0.26    
##                            reading_t1 attitude_total_t1 TOTALACIRICHILDT1
## child_interest_total_t1                                                  
## adults_literacy_total_t1                                                 
## press4achievement_total_t1                                               
## availability_t1                                                          
## reading_t1                                                               
## attitude_total_t1            0.04                                        
## TOTALACIRICHILDT1           -0.03             -0.44                      
## TOTALACIRIADULTT1            0.08             -0.51*             0.62**