Showing posts with label hypothesis testing. Show all posts
Showing posts with label hypothesis testing. Show all posts

Tuesday, September 30, 2008

Meeting Summary for 9/30/2008

I spoke about FDR Correction and gave a brief outline of the methods involved in Multiplicity Adjustment and FDR Correction:
Multiplicity/ P Value Adjustment

- Single Step
---Boneferonni
---Sidak

- Step-down
---Holms
---Westfall & Young (min P/ max T)

FDR Correction
---Benjamini & Hochberg

Useful reference for this is : Benjamini & Hochberg 1995, J. Roy. Statist. Soc. Ser. B 57:289-300

Jang went over Hypergeometric tests, Fisher's exact test and its difference with Chi Squared Test.

For the next meeting(Friday instead of Thursday), Mike said he would look at applying Fisher's exact test and FDR Correction(GoMiner).

We also decided we would start off with an introduction to regression.

Thursday, September 25, 2008

Meeting Summary for 9/25/08

I gave an overview of T-tests and ANOVA. For further information see their respective wikipedia articles. Linked here are some slides from Philip Stafford's biostatistics class a few years ago: http://www.public.asu.edu/~mverdic/stafford/

Ina gave an overview of the Binomial test Chi-square test, and saved details of KS and DA tests for Tuesday. She'll post any relevant documents in the comments of this post.

Jang will discuss Fisher's exact and Hypergeometric tests on Tuesday. He will post any pre-reading materials here in the comments.

Archana discussed p-value correction. She will discuss FDR and the beginnings of regression analysis on Tuesday. She will post any references to her talking points and pre-reading materials in the comments.

Next meeting is Tuesday at 9ish.

Tuesday, September 23, 2008

Summary for Tuesday 23 September

Today we reviewed the papers posted from last time and discussed hypothesis testing and p-value usage in papers. Here are the tasks for Thursday's meeting:

Mike: Brief overview and examples for T-test/F-test/ANOVA
Ina: Brief overview and examples for Chi-Square-Test/Binomial Test/KS-Test/DA-Test
Jang: Brief overview and examples for Hypergeometric Test/Fisher's Exact Test
Archana: Overview of FDR/Corrections/P-Value Adjustments for task distribution.

Next time we will also revise the semester schedule. Please post references, links and other resources you encounter in your studies.

Monday, September 15, 2008

Meeting Summary for 9/15/08

Ina discussed how we can apply hypothesis testing to the gene expression data from microarrays. We got to know difference in Z-statistic formula when applied to observations directly versus the mean of observations (which follows the Normal Distribution according to the Central Limit theorem). The rest of the chapter on Hypothesis Testing will be studied individually and an overview of tests will be discussed on Wednesday, when they are applied, how they are applied and differences between tests conducted in same scenarios.

References :
1. X. Cui, G. A. Churchill, "Statistical tests for differential expression in cDNA microarray experiments", (Review), Genome Biology 2003, 4:210.
2. J. A. C. Sterne, G. D. Smith, "Sifting the evidence - what's wrong with significance tests?", (Education and Debate)BMJ, 27 January 2001, Volume 322.

Wednesday, September 10, 2008

Meeting Summary for 9/10/08

Ina went over a brief summary of Point Estimation and a general overview of Hypothesis Testing. Mike went over a paper he had found on normalization and statistical analysis of microarray experiments. We decided to finish the chapter on Hypothesis Testing, and read some papers on microarray normalization. I've posted the review papers on normalization on Citeulike (tagged by csbstudy and normalization).