Welch’s two-sample t-test (as opposed to Student’s) given lack of homogeneity of variance, and two groups are completely independent (no overlap in students)
Levene’s test for spread as distribution is not normal (required for F-test)
$accuracy_mean_test
Welch Two Sample t-test
data: Accuracy by type_10
t = -6.1644, df = 1994.4, p-value = 8.541e-10
alternative hypothesis: true difference in means between group Irregular and group Regular is not equal to 0
95 percent confidence interval:
-0.07377433 -0.03816238
sample estimates:
mean in group Irregular mean in group Regular
0.7644619 0.8204303
$rcpm_mean_test
Welch Two Sample t-test
data: RCPM by type_10
t = -11.004, df = 2290.2, p-value < 2.2e-16
alternative hypothesis: true difference in means between group Irregular and group Regular is not equal to 0
95 percent confidence interval:
-1.583494 -1.104480
sample estimates:
mean in group Irregular mean in group Regular
5.353307 6.697294
$accuracy_levene
Levene's Test for Homogeneity of Variance (center = median)
Df F value Pr(>F)
group 1 394.51 < 2.2e-16 ***
2467
---
Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
$rcpm_levene
Levene's Test for Homogeneity of Variance (center = median)
Df F value Pr(>F)
group 1 13.524 0.0002405 ***
2467
---
Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1