A Conceptual Introduction to Item Response Theory: Part 2. IRT Is a Probability Model

[@drmennaallah]

it is very nice well prepared video god bless you .

[@ilgncebioglu1352]

This was extremely helpful! Thank you very much for the excellent explanation!

[@lefanjard]

thanks Karon - this is a great series for students :)

[@rebeccaworsham1182]

Hello! What is the difference between theta and a logit? How does one compute theta from raw scores? Thanks so much for your videos, they are a wonderful resource.

[@karoncook]

These are innacurately credited to Yen Ling Lam. Not sure why, since I developed them. Karon Cook

[@jepurpura]

and where does it come from?

[@sarahlachance7506]

What does the 1+ in the denominator do?

[@janmeeuwissen899]

Just a trick to make sure that we are getting a number between 0 and 1. If you take ANY number and divide it by 1+ that number, the answer will always be between 0 and 1.

[@einsteinwallah2]

what is "n" in theta(n) on right hand side?

[@tajmartin-simpson3780]

Person?

[@einsteinwallah2]

@@tajmartin-simpson3780 yes it is and he says so too at 4:13 but thanks for reply ... i must have missed when i saw this video first

[@BryanTanner]

I'd like for this video to emphasize the distinction between "likelihood" and "probability."

[@jepurpura]

why the constant 2.7?

[@tseeiks1250]

It's Euler's Number en.wikipedia.org/wiki/E_(mathematical_constant)

[@Fracasse-0x13]

The question was why not what is​@@tseeiks1250

[@jeremyjaytaylor1]

Very we'll done, Karon.

[@universalsoulmate]

very useful! thanks so much!

[@jeremyjaytaylor1]

well*... Darn autocorrect

[@eunicecui9005]

person n