Practical Predictive Analytics

Simulating the negative cases

We just simulated the positive cases. Now, let's set up some similar code to simulate the non-diabetes patients (outcome=0).

For the negative cases, we will also multiply sample.bin by -1, so that in the future, we know that all the positive sample.bin instances correspond to positive cases and all the negative sample.bin instances correspond to negative ones:

set.seed(123)  nbins2=base::round(n2/400,0) correlationMatrix <- cor(PimaIndians[PimaIndians$diabetes =='neg',1:8])  covarianceMatrix <- stats::cov(PimaIndians[PimaIndians$diabetes =='neg',1:8])  out_sd2 <- as.DataFrame(data.frame(data.frame(  sample.bin=base::sample(1:nbins2,n2,replace=TRUE)*(-1),   outcome=0,  mvrnorm(n2, mu = means.neg, Sigma = matrix(covarianceMatrix, ...