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Member Training: How to Avoid Common Graphical Mistakes

December 1st, 2019 by

Good graphs are extremely powerful tools for communicating quantitative information clearly and accurately.

Unfortunately, many of the graphs we see today confuse, mislead, or deceive the reader.

These poor graphs result from two key limitations. One is a graph designer who isn’t familiar with the principles of effective graphs. The other is software with a poor choice of default settings.

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Member Training: Practical Advice for Establishing Reliability and Validity

October 30th, 2019 by

How do you know your variables are measuring what you think they are? And how do you know they’re doing it well?

A key part of answering these questions is establishing reliability and validity of the measurements that you use in your research study. But the process of establishing reliability and validity is confusing. There are a dizzying number of choices available to you.

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Member Training: Interpretation of Effect Size Statistics

August 30th, 2019 by

Effect size statistics are required by most journals and committees these days ⁠— for good reason. 

They communicate just how big the effects are in your statistical results ⁠— something p-values can’t do.

But they’re only useful if you can choose the most appropriate one and if you can interpret it.

This can be hard in even simple statistical tests. But once you get into  complicated models, it’s a whole new story. (more…)


Member Training: A Predictive Modeling Primer: Regression and Beyond

May 31st, 2019 by

Predicting future outcomes, the next steps in a process, or the best choice(s) from an array of possibilities are all essential needs in many fields. The predictive model is used as a decision making tool in advertising and marketing, meteorology, economics, insurance, health care, engineering, and would probably be useful in your work too! (more…)


Member Training: Non-Parametric Analyses

April 1st, 2019 by

Oops—you ran the analysis you planned to run on your data, carefully chosen to answer your research question, but your residuals aren’t normally distributed.

Maybe you’ve tried transforming the outcome variable, or playing around with the independent variables, but still no dice. That’s ok, because you can always turn to a non-parametric analysis, right?

Well, sometimes.
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Member Training: What’s the Best Statistical Package for You?

February 1st, 2019 by

Choosing statistical software is part of The Fundamentals of Statistical Skill and is necessary to learning a second software (something we recommend to anyone progressing from Stage 2 to Stage 3 and beyond).

You have many choices for software to analyze your data: R, SAS, SPSS, and Stata, among others. They are all quite good, but each has its own unique strengths and weaknesses.

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