Which Statistics To Use?

I am looking at the effects of 4 different driving training methods on 4 different groups of people. My dependent variables are thier number of accidents, number of points on driving record, and number of citations at 3 months after receiving their license and then a year later after receiving their license. What test do I use to determine if any of the training methods were effective?

Also each group will be rating their perceptions of effectiveness using a likert scale. What test would I use to determine if there are any differences amongst the four groups in the perceptions of effectiveness?

thank you much!!:)


TS Contributor
On each dependent variable, do a 1-way ANOVA.

I would not recommend MANOVA since it requires you to combine the DV's into one linear combination, and in this case it doesn't make sense to do so.
Thank you very much for your help. I guess I am not really understanding the differences between a MANOVA and an ANOVA. Why is it not advantageous to include all the DV's into on combination? Don't I inflate my Type 1 error rate when I perform multiple one-way ANOVA's? Much thanks!! This site is wonderful!


TS Contributor
Technically, yes, your Type I error rate will go up, but it's not a big deal because I'm assuming that you planned, as part of your study, prior to collecting data, to examine these variables....

MANOVA will tell you which IVs are significant for a specific linear combination of DVs, which may or may not make sense from a practical viewpoint.

If you were able to combine the DVs into a meaningful, composite "index" of driver safety, then OK, maybe MANOVA makes sense.