Hello
I've conducted an experiment with around 100 people. I have 48 male and 52 female. Now I would like to accept or reject the following three hypothesis (i.e. to determine the p-value):
- There is a difference in performance between male and female (The people had to perform some tasks which gives me a continuous performance value for every person, i.e. I have a value per person).
- There is a difference in performance between groups of people (independent of the gender). The performance metric is the same as under 1. but now I have divided the people in four different groups. The groups have unequal sizes.
- There is a difference in performance depending on the age of people (I have also recorded the age of the people). I have ages from 18 to 30. For example, for age 18 I only have one person, for other ages there are multiple persons.
What statistical test (like t-test, ANOVA, chi-squared, Friedmann, Kruskal-Wallis, Mann-Whitney) would be appropriate for the three cases described above?
Second, does it matter if I choose There is a difference in performance between male and female or the negation There is no difference in performance between male and female as the null hypothesis?