- Make five graphs of api99: histogram, kdensity plot, boxplot, symmetry plot and normal quantile plot.
- What is the correlation between api99 and meals?
- Regress api99 on meals. What does the output tell you?
- Create and list the fitted (predicted) values.
- Graph meals and api99 with and without the regression line.
- Look at the correlations among the variables api99 meals ell avg_ed using the corr and pwcorr commands. Explain how these commands are different. Make a scatterplot matrix for these variables and relate the correlation results to the scatterplot matrix.
- Perform a regression predicting api99 from meals and ell. Interpret the output.