A brief introduction to one-way Analysis of Variance (ANOVA). I discuss the null and alternative hypotheses and conclusions of the test. I also illustrate the difference between and within group variance using a visual example. In other related videos, I discuss the ANOVA formulas in detail and work through a real-world example.
I look at the calculation formulas and the meaning of the terms in the one-way ANOVA table. In other related videos, I have a brief introduction to one-way ANOVA, and work through a real world example.
The example and data used here is based on information and summary statistics from: Grattan-Miscio, K. and Vogel-Sprott, M. (2005). Alcohol, intentional control, and inappropriate behavior: Regulation by caffeine or an incentive. Experimental and Clinical Psychopharmacology, 13:48-55.
Finding significance in a one-way ANOVA F test means there is strong evidence that not all population means are equal. Which are different? We can explore that with a multiple comparison procedure. Here we look at the simplest one: Fisher’s LSD confidence intervals.
An example of finding the p-value in one-way ANOVA. The p-value (the area to the right of the F test statistic) is found using both the F table and the statistical software R.