There are responses of my school's alumni on the skills they perceive they acquired during the studies and are required from their job now. 18 skills evaluated from 1 to 5 (ordinal values, right?). Also they are 18 classes of graduation (around 30 responses from each year). There are also such attributes of the respondents as a master's degree, current status, so on. There is no regression model I could construct up to this moment, but I'm at least interested if the difference in averages of the skills between different groups are significant. I try R over and over. I managed only to tabulate the means for the groups. But then I'm lost.
- Are there tests I should run the data through first?
- How to know what distribution my data follows?
- And what are the ways to see if the means differ significantly across the groups?
- Is it possible without a regression model at all?