jamovi

Hello!

I am doing an Item Analysis with Jamovi and I am not quite sure which mean value I have to use for computing the item difficulty. The mean value of the items computed with the "descriptives" option is different from the mean value of the items when using the item statistics mean of the reliability analysis.

So which mean value is best for computing the item difficulty?
And why do these two means differ?


Thanks!

you can download "snowIRT" module in the jamovi library. you will get the "proportion" and IRT "measure", which can be used as item difficulty.