Wjastle

Hello, Wjastle! Welcome to Wikipedia! Thank you for your contributions to this free encyclopedia. If you decide that you need help, check out Getting Help below, ask me on my talk page, or place {{helpme}} on your talk page and ask your question there. Please remember to sign your name on talk pages by clicking or using four tildes (~~~~); this will automatically produce your username and the date. Finally, please do your best to always fill in the edit summary field. Below are some useful links to facilitate your involvement. Happy editing! Million_Moments (talk) 10:30, 27 June 2008 (UTC) Getting started A tutorial • Our five pillars • Getting mentored How to: edit a page • upload and use images Getting help Frequently asked questions • Tips Where to ask questions or make comments Request administrator attention Policies and guidelines Neutral point of view • No original research Verifiability • Reliable sources • Citing sources What Wikipedia is not • Biographies of living persons Manual of Style • Three-revert rule • Sock puppetry Copyrights • Policy for non-free content • Image use policy External links • Spam • Vandalism Deletion policy • Conflict of interest • Notability The community Build consensus • Resolve disputes Assume good faith • Civility • Etiquette No personal attacks • No legal threats Community Portal • Village pump Signpost • IRC channels • Mailing lists Writing articles Be bold in editing • Develop an article The perfect article • Manual of style Stubs • Categories • Disambiguation Pages needing attention • Peer review Miscellaneous User name • User pages • Talk pages Clean up: General - Spam - Vandalism Join a WikiProject • Translation Useful templates • Tools • User scripts

{{}}

Polygamma in Beta Distribution Higher Moments section

Wjastle,

Could you please double check your math?

Instead of your posted result:

$\operatorname {E} (\log ^{2}X)=\psi ^{2}(\alpha )-\psi ^{2}(\alpha +\beta )+[\psi ^{(1)}(\alpha )-\psi ^{(1)}(\alpha +\beta )]^{2},$

I get:

$\operatorname {E} (\log ^{2}X)=(\psi (\alpha )-\psi (\alpha +\beta ))^{2}+\psi ^{(1)}(\alpha )-\psi ^{(1)}(\alpha +\beta ),$

same problem for the other result

Thanks,

Dr. J. Rodal (talk) 01:04, 11 August 2012 (UTC)

Yes you are right, I got the notation confused: mixed powers and orders of poly-gammas.

• I just added "Should the Mean and the Variance based on Ln[X] (rather than X) be included in the statistical property box?" to the Beta Distribution talk page. It will be interesting to hear your views on this subject, and for our Wikipedia community to arrive at a consensus. Thanks Dr. J. Rodal (talk) 15:30, 11 August 2012 (UTC)