I'm doing a stats assignment and for one of the questions I need to make a judgement of whether there is skew and kurtosis from a p-p plot in SPSS. I've been over the lecture, and we were told to look for "snaking" around the line for skew, and points "hanging" off the line for kurtosis. I'm having trouble telling just from eyeballing it - the examples they used in the lecture haven't made it clear to me how to differentiate accurately between skew and kurtosis. Can you tell me how to make the call exactly? Here's the p-p plot.
There is some curvature in the upper end of the plot, not in the lower end. That could indicate some skew in the distribution. The effects are small, so difficult to say if what we see is significant. You could simulate an envelope around the plot. Also, have a look at the answers here: Interpreting QQplot - Is there any rule of thumb to decide for non-normality?
I don't think I would try to assess kurtosis from that plot!