Post-hoc tests, pairwise or other linear contrasts, are typical in an analysis of variance (ANOVA) setting to understand which group means differ. They incorporate p-value adjustments to avoid concluding that group means differ when they actually do not. There are several adjustments that can be considered for conducting multiple post-hoc tests, including single-step and stepwise adjustments. (more…)
Membership Webinars
Member Training: ANOVA Post-hoc Tests: Practical Considerations
October 1st, 2021 by TAF Support
Member Training: Matrix Algebra for Data Analysts: A Primer
August 31st, 2021 by Karen Grace-Martin
If you’ve been doing data analysis for very long, you’ve certainly come across terms, concepts, and processes of matrix algebra. Not just matrices, but:
- Matrix addition and multiplication
- Traces and determinants
- Eigenvalues and Eigenvectors
- Inverting and transposing
- Positive and negative definite
Member Training: Moving to a World Beyond p<0.05
August 2nd, 2021 by TAF Support
For nearly a hundred years the concept of “statistical significance” has been fundamental to statistics and to science. And for nearly that long, it has been controversial and misused as well. (more…)
Member Training: A (Gentle) Introduction to k-Nearest Neighbor
July 1st, 2021 by TAF Support
Missing data is a common problem in data analysis. One of the successful approaches is k-Nearest Neighbor (kNN), a simple approach that leverages known information to impute unknown values with a relatively high degree of accuracy. (more…)
Member Training: An Introduction into the Grammar of Graphics
June 1st, 2021 by TAF Support
As it has been said a picture is worth a thousand words and so it is with graphics too. A well constructed graph can summarize information collected from tens to hundreds or even thousands of data points. But not every graph has the same power to convey complex information clearly. (more…)
Member Training: Writing Study Design and Statistical Analysis Plans
May 3rd, 2021 by TAF Support
One component often overlooked in the ‘Define & Design’ phase of a study, is writing the analysis plan. The statistical analysis plan integrates a lot of information about the study including the research question, study design, variables and data used, and the type of statistical analysis that will be conducted.