I need some beginner help with the Mann-Whitney U test, I'm just trying to learn SPSS on my own... I'm having trouble formulating my answer.
I have two sets of restaurant review scores/ratings for a single restaurant. So basically there are two different ways to rate a restaurant, with slightly different numerical systems and the data is collected in different ways. I'm trying to compare these two rating systems with the test to see if the results differ, if the other rating system gives higher ratings, or if the rating systems work in the same way for this one particular restaurant. (English is not my language, I hope you understand what I'm doing!)
I tested the two rating systems with the Mann-Whitney U test. Here are the results:
Mann-Whitney U: 19,000
Wilcoxon W: 55,000
Asymp. Sig. (2-tailed): ,252
Exact Sig. [2*(1-tailed Sig.)]: ,336b
I think the key is the 2-tailed sig, which indicates that there is not a significant difference between the two types of rating systems. But how do I formulate this into an answer? This means that the rating systems both work in the same way and looks like the results are very similar. But what do the other results (for example Z: -1,147 or the Mann-Whitney U: 19,000) indicate and how should I include them in my answer? Any help is welcome.