Another way to encode categorical variables is a method that SAS/JMP calls nominal. I will illustrate it with using three variables in the model. This form is appropriate to use when using an ANOVA model, and when you need a full-rank design matrix (e.g. regstats requires this)....
Complete the following ANOVA summary table. How many conditions were in the study? Factorial Design: It is often required to analyze the joint effects of two factors on a dependent variable. For example, studying the effec...
The general guideline is to use linear regression first to determine whether it can fit the particular type of curve in your data. If you can’t obtain an adequate fit using linear regression, that’s when you might need to choose nonlinear regression. Linear regression is easier to use, s...
(TABLE)... Question: Complete the following ANOVA summary table. How many subjects were in the study? Two-Way Factorial ANOVA: A research design that involves studying the relationship of two factors each having two or more ...
To represent a significance level of 0.05, I’ll shade 5% of the distribution furthest from the null value. The two shaded regions in the graph are equidistant from the central value of the null hypothesis. Each region has a probability of 0.025, which sums to our desired total of 0.05. ...
Preliminary plots of the residuals of the dependent variable against the predicted value of the dependent variable indicated mild hetero- scedasticity in the data. However, the continuous vari- ables were categorised using bins, nullifying the effect of transforming the data. Thus, only the ...