Slides are here:
To prepare for this class:
A. Please read the following:
- from PDQ Statistics, pages 41-52 “Comparison Among Many Means: ANOVA”
B. Please consider the following questions for discussion in class:
- What are different sources of variability within a dataset?
- What is “within group” variability and how does it compare with “between group” variability?
- What is the null hypothesis for an ANOVA?
- What methods can we use to visualize the relationship between a continuous variable and a categorical variable?
C. Get your radon dataset ready for analysis
- Ensure that you know how to define the reference category for categorical variables in Deducer
Objectives of this class:
A. Hypothesis generation for categorical variables
- Which variables in the radon dataset are categorical?
- How might they be associated with the radon concentrations?
- How can we test our hypotheses?
B. Visualization of continuous variables by categorical variables
- Density plots for each value of the dichotomous variable
- Box plots
C. Comparing the means to multiple groups of samples
- ANOVA (analysis of variance)
- Overall association with the categorical variable
- Association with specific categories of the variable
D. Simple linear regression
- Dependent and independent variables
- The null hypothesis
- Dummy variables for categorical variables
- Interpretation of coefficients
- Standard reporting
Last updated on February 2, 2017 @4:44 pm
