Aims

Objectives

The following objectives will help you to assess how well you have mastered the relevant material. By the end of this section you should be able to:

• State the model assumptions under which a simple linear regression model is appropriate for describing and analysing a set of data consisting of predictor values and corresponding response values.

• Produce a scatter plot of response values against predictor values, both by hand and in R.

• Compute least squares estimates of the slope and intercept of the fitted regression line, by hand and in R, and add the line to a scatter plot of the data.

• Comment critically on any deviations from the assumptions of the model that are apparent from the plot of the data values together with the fitted regression line.

• Compute the fitted values and the residual values, plot the residual values against either the predictor values or the fitted values, and comment critically on any deviations from the assumptions of the model that are apparent from the plot.

Suggested Reading

Handouts and Problem Sheets

Questions - set this week

PROBLEM SHEET 4 -- Question 1, 2, 3

Interesting links