topic Re: Omega hierarchical (reliability) in Discussions

Omega hierarchical (reliability)

profjmb — Sat, 21 Mar 2020 21:54:09 GMT

My snobby psychometrics colleagues don't like alpha (even though it's used 98% of the time), because one can get a high alpha even if one has no general factor. Omega (hierarchical; not general) is the solution. I am writing to plea for consideration for future JMP (or if anyone is sufficiently challenged, an add-in). Thanks.

Re: Omega hierarchical (reliability)

txnelson — Sat, 21 Mar 2020 22:09:58 GMT

Make sure you submit the request to the JMP Wish List?

Re: Omega hierarchical (reliability)

LauraCS — Mon, 23 Mar 2020 16:42:26 GMT

Thank you @profjmb! It's a great suggestion. I just added it to our to-do list. We'll eventually get to it!

Best,

~Laura

Re: Omega hierarchical (reliability)

LauraCS — Tue, 09 Jun 2020 13:36:45 GMT

Hello @profjmb,

I just wanted to let you know that JMP 16.0 will have an option to obtain coefficient omega from a CFA. Whether users obtain omega hierarchical or general will depend of the type of CFA that was fit. For example, a standard CFA with 3 factors would result in omega_general for subscales. However, if such CFA is extended to a bifactor model (by adding a general factor that loads on all manifest variables), the result will be omega_hierarchical for the general factor and omega_hierarchical for subscales for the group factors. This follows the review of omega coefficients in Rodriguez, Reise, & Haviland (2015). These options are available in the Early Adopter program so we'll keep improving them as we receive feedback.

Thank you again for your suggestion!

~Laura

Re: Omega hierarchical (reliability)

Fernando — Fri, 24 Jul 2020 22:28:07 GMT

Hi Laura,

Thanks for the info.

I'm trying to obtain the coefficient omega using the early adopter but I cannot find it.

Please could you provide indications about where to find it in the program?

Thanks

Re: Omega hierarchical (reliability)

LauraCS — Mon, 27 Jul 2020 11:48:27 GMT

Dear @Fernando,

We included coefficient omega as part of a "mini dashboard" of related statistics that quantify the adequacy of the measurement model at hand, thus, you'll find it in under the red triangle menu for a fitted model as, "Assess Measurement Model."

Best,

~Laura