study 2 designs:
2 (Mindset: perspective-taking vs. objective) by
2 (Gender: male vs. female) by
3 (Condition: Personal Need vs. Abstract Need vs. Aphorism)
study 3 designs:
2 (Mindset: perspective-taking vs. objective) by
2 (Gender: male vs. female) by
3 (Condition: Personal Need vs. Abstract Need vs. Aphorism) by
2 (Type: Covid-19 vs. general)
test of interest for study 3:
my guess is we will try to study it with linear regression–so estimating here!
diffScor = \(\beta_0\) + \(\beta_2\)CovidvGeneral + \(\beta_2\)MvF + \(\beta_3\)PerspvObj + \(\beta_4\)type1 + \(\beta_5\)type2 + \(\epsilon_i\)
study 2 test for main effect of Covid-19 vs. aphorism statements:
diffScore = \(\beta_0\) + \(\beta_1\)ApvPN + \(\epsilon_i\)
# 2. ME of covid-19 vs. aphorism
#take perspective taking condition
d2 <- as.data.frame(cbind(participant = dp1$participant, ap_catscore = dp1$ap_p_catscore, pn_catscore = dp1$pn_p_catscore))
#take remain objective condition
d3 <- as.data.frame(cbind(participant = do1$participant, ap_catscore = do1$ap_o_catscore, pn_catscore = do1$pn_o_catscore))
#merge to single dataset
d4 <- as.data.frame(rbind(d2, d3), na.pass = T)
t.test(d4$ap_catscore, d4$pn_catscore, var.equal = F, paired = T)
##
## Paired t-test
##
## data: d4$ap_catscore and d4$pn_catscore
## t = 3.9685, df = 269, p-value = 9.284e-05
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
## 0.3746517 1.1123854
## sample estimates:
## mean of the differences
## 0.7435185
#t = 3.9685, df = 269, p-value = 9.284e-05
#f_val = (PRE/(PA - PC))/((1 - PRE)/(n-PA))
f_val = 3.9685^2
f_val #[1] 15.74899
## [1] 15.74899
n = nrow(d4)
n
## [1] 270
PA = 2
PC = 1
PRE = 15.74899/(268+15.74899)
#get true PRE
eta_sq = 1 - (1-PRE)*((270-1)/(270-2))
eta_sq #0.051979
## [1] 0.051979
pwr.f2.test(u = 6, f2 = .052, sig.level = .05, power = .80)
##
## Multiple regression power calculation
##
## u = 6
## v = 261.3675
## f2 = 0.052
## sig.level = 0.05
## power = 0.8
#total sample size needed: 262
study 2 test for interaction for empathy manipulation and covid-19 vs. non-covid personal need statements:
# Interaction for empathy manipulation and covid vs. non-covid (study 2)
t.test(dp1$pn_p_catscore, do1$pn_o_catscore, var.equal = F, paired = F)
##
## Welch Two Sample t-test
##
## data: dp1$pn_p_catscore and do1$pn_o_catscore
## t = 1.9028, df = 255.8, p-value = 0.05819
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
## -0.01697305 0.98798754
## sample estimates:
## mean of x mean of y
## 0.6250000 0.1394928
## #t(255.8) = 1.9028, p = .05819, CI = [-0.017, 0.988]
n = nrow(dp1) + nrow(do1)
n
## [1] 270
f_val = 1.9028^2
f_val #3.620648
## [1] 3.620648
PRE = 3.62/(268+3.62)
PRE
## [1] 0.01332744
PA = 2
PC = 1
eta_sq = 1 - (1 - PRE)*((n - PC)/ (n - PA))
eta_sq #.01
## [1] 0.009645829
pwr.f2.test(u = 6, f2 = 0.01, sig.level = .05, power = .80)
##
## Multiple regression power calculation
##
## u = 6
## v = 1361.737
## f2 = 0.01
## sig.level = 0.05
## power = 0.8
#total sample size needed: 1362, this is about 230 subjects per cell