Binary Response, Three Potential Predictors, Independent Observations

In a hypothetical study, a sample of 500 subjects had three potential predictors measured: age, sex, and systolic blood pressure, and a diagnosis of a certain disease (present/absent) was made. There is assumed to be no interaction between age and blood pressure. The relationship between continuous variables and the probability of disease is smooth. The data are found in the attachments below. To read the dataset into R you can run save the .rda file to a temporary area, then load('prob1.rda') which will create a data frame d in your workspace (search position 1). Alternatively, you can load the file ready for analysis directly from the WWW using loadURL('http://biostat.mc.vanderbilt.edu/twiki/pub/Main/Puzzler1/prob1.rda').

Find a model that fits these data reasonably well. -- FrankHarrell - 09 May 2004

Request: May I get a didactic but introductory reference to the assumptions implied by the statement "The relationship...is smooth?". -- DavidAirey 17 May 2004