Could mud-wrestling be the cause of a rash contracted by University of Washington students in the spring of 1992? Two physicians at the University of Washington health center wondered this when one male and six female students complained of rashes after participating in a mud-wrestling event. Questionnaires were sent to students in the residence halls that participated in the event. The questionnaire asked about the appearance of a rash and about attendance at the mud-wrestling event. The results, by gender, are summarized in the following table.
Let x be the indicator variable .
We wish to fit a logistic regression model log
= β0 + β1x
where p is the binomial probability of developing a rash and log is the natural logarithm. The estimate b1 of 1 based on the data in our table is
A. -1.557.
B. -1.152.
C. 0.405.