Blog

The Decided Voter: Journey into The Twilight Z…, um, Selection Bias

In the week following the first presidential debate, I was listening to a local talk radio host talking with caller who was a Trump supporter. The exchange went something like this: Caller: “I don’t believe anything that comes out of Hilary’s mouth. Everything she says is a lie.” Host: “Nothing she said is true? So…

Grit. A Researcher’s Best Friend

Instead of writing about a statistical concept in this post I wanted to share something I’ve discovered about myself and other successful people I’ve worked with. I am hoping you will also find it useful and fun… I find a large part of being a private practice statistical consultant is talking people down from the…

Statistical Significance Guaranteed!? A Problem of Overpowering

In September, 2016, I will present a webinar about a priori power analysis for determining a proper sample size, a very important aspect in the design stage of a study.  We will see how a sample that is too small will result in an inability to see significance that is truly present in our data. …

When Dummy Coding is the Wise Thing to Do

Coding groups on nominal (categorical) groups of an independent variable is not a problem in analyses such as t-tests or ANOVA. However, things can fall apart fairly quickly if nominal variables are not coded properly for use as predictors in linear models such as multiple regressions. Let’s take a simple example of a variable for…

Regression Tips – Dummy Coding

One interesting and very useful aspect of dummy coding is the ability to use these dichotomously coded variables as predictors in a regression model. A regression model does just that, it models something, represents something. Let’s investigate a hypothetical model of stress.  We want to see if biofeedback training and gender have an effect on…
Share This

Share This

Share this post with your friends!