Question

Which of the following is true?

A. When the p-value is less than 0.05 for an independent samples t test, the 95% confidence interval of the difference between groups will cross zero.

B. When the p-value is larger than 0.05 for any test, it means that the effect size is zero.

C. When the p value is larger than 0.05 for an independent samples t test, it means that there are no significant differences between groups at the level of alpha = .05.

Answer 1

pvalue <0.05 indicates statistical significance. If a 95% confidence interval crosses the value 0, then there is no statistically meaningful or statistically significant difference between the groups. So A is not true

p_value>0.05 implies that the data has not provided enough evidence to reject the null hypothesis. So that doesn't mean that effect size which is the difference between the group means is zero. It only means that the difference is not statistically significant at the given significance level. so B is not true

So only C follows