We looked at the distributions of each of the variables. The distribution of the hotness ratings were skewed to the right. The distribution of overall ratings was skewed to the left.
Then we looked at the data in order to answer this question:
Do easier professors get higher overall ratings?
We looked at a crosstab of overall ratings by easiness. We found that the answer appears to be yes. An overwhelming majority (over 70%) of professors who were rated as very easy also got very high overall ratings. Meanwhile, professors who were rated as very difficult were very unlikely to get a very high rating.
OK - if people rate their professors partly based on how easy the class was, how do we know who is really a "good teacher"? How do we separate out "good teaching" from simple easiness?
Next week, we will look at a method that allows you to do this.
For homework, please read pp. 292-297 and pp. 300-305 about regression. This is the technique we will be using with the RateMyProfessor data.