Five different doses of insecticide were applied under standardized conditions to an insect species. The data are as followed:
Dose (mg/l): 2.6 3.8 5.1 7.7 10.2
Number of insects: 60 60 59 57 60
Number killed: 7 16 20 48 54
I was asked to build a logistic regression model which says the logit of the chance of death changes linearly with the natural logarithm of dose.
I did this in SAS.
I'm asked to give a 95% Likelihood Ratio Confidence Interval for B. Further, translate this interval into an interval for the effect on the odds of death of increasing the dose by 50% (i.e, multiplying the dose factor by 1.5) and interpret. Hint: First translate the multiplying dose factor to the natural log scale.
I'm not sure how to do this, I've attached the appropriate SAS output I think I need to do the question with. I'm thinking take the B estimate (logc in the output is my B estimate) and exponentiate it, then times that value by 1.5. If thats right, what do i do next? same thing to the end points of the confidence interval associated with B?
Please advise!