type I error - non parametric stats

[johnboy]

i have run multiple non parametric stats to analyse my data. i read that you cannot make a type I error because the data is not normally distributed, and therefore it is fine to run multiple tests. however, running multiple parametric stats is likely to cause a type I error. is my understanding correct?

thanks

[JohnM]

You can make Type I and Type II errors with nonparametric tests, and with running multiple tests, just like you can with parametric tests.

However, since nonparametric tests tend to be slightly less powerful than parametric tests, the probability of a Type I error is going to be a little lower.