Hypothesis testing

- Before we prepare our hypothesis test,…let's briefly recap our example.…A company is trying to figure out if a new drug…is effective in reducing the chance of a heart attack.…The company gathers a large number of subjects.…The subjects are randomly placed into two groups.…One group of subjects is given this new drug.…The other group of subjects is given a placebo.…The people in the study are not to be told…if they are getting the new drug or the placebo.…

The results of the study were as follows.…For the new drug, we had a sample size 2,219.…26 of those people had a heart attack,…so our p-hat was 26 divided by 2,219.…For our placebo group, we had a sample size of 2,035.…In this case, 46 people had a heart attack,…so our p-hat here was 46 divided by 2,035.…The results and the resulting 95% confidence interval…both provide evidence that the new drug…did help reduce the rate of heart attacks.…

The question we have is,…what's the probability that our results happened by chance?…In other words,…we had 4,254 people…