bonferroni correction

I recently presented some work in my department in which my colleagues and I had applied a Mann-Whitney U test for multiple pairwise comparisons. We used a Bonferroni-adjusted alpha for the test. After my presentation, a guy generally considered to be a statistics whiz told me that the...

Hi, I have a question regarding multilevel analyses using stata. My research question concerns a nested observational study design in which i collect questionnaire data from students (that cluster within classes, that cluster within schools: a 3 level design). Together with a set of...

I am conducting a hierarchical multiple regression with 6 predictor variables (2 dichotomous, 1 continuous, 3 2-way interactions) entered over 4 steps. I know that I need to control for Type I error with so many predictors, and I'm thinking of using a Bonferroni correction. My question is: do I...

Hello, I have 6 independent groups and one dependent variable. I did a univariate ANOVA analysis and the overall group significance was not significant. Is it okay to compare individual groups with the control group and do a series of unpaired t-tests? Do I need to do a Bonferroni...

Hi, I'm doing my dissertation for my Masters and I am in desperate need of help! I need to run 4x2 chi-squares in SPSS. I understand the assumptions (all expected counts must be above 1 and there should be no more than 20% of expected counts below 5), however as I am running multiple tests...

I have been using SPSS for about four months. I am not a statistician. I continue to learn something new every minute that I am working with this program. I am looking at scores for achievement levels based on race. When I run the data, here are my steps: [LIST=1] Analyze multivariate...