3. How does level of affluence affect health care? To address one dimension of the problem a group of heart attack victims was selected. Each was categorized as a low-, medium-, or high-income earner. Each was also categorized as having survived or died. A demographer notes that in our society 21% fall into the low-income group, 49% into the medium-income group and 30% are in the high-income group. Furthermore, an analysis of heart attack victims reveals that 12% of low-income people, 9% of medium-income people and 7% of high-income people die of heart attacks.
a. What is the probability of dying from a heart attack?
b. Find the probability that a survivor of a heart attack is in the low-income group.
4. Random samples from two normal populations produced the following statistics:
ð‘ 12=350,ð‘›1=30,ð‘ 22=700,ð‘›2=30
a) Can we infer at the 10% significance level that the two population variances differ?
b) Now, repeat part a) changing the sample sizes to 15. What happens to the test statistic when the sample size decreases?
The answer to this question... View the full answer