6. In an investigation of environmental causes of disease, data were collected on the annual mortality...
72. Hard water by region Recall from Chapter 7, Exercise 75, that data were collected on the annual mortality rate (deaths per 100,000) for males in 61 large towns in England and Wales. In addition, the water hardness was recorded as the calcium concen- tration (parts per million, ppm) in the drinking water. The dataset also notes, for each town, whether it was south or north of Derby. Is there a significant difference in mortality rates in the two re-...
Data were collected on the annual mortality rate (deaths per 100,000) for males in 61 large towns in England and Wales. The data set also notes for each town whether it was south or north of Derby. The summary statistics are given below. Is there a significant difference in mortality rates in the two regions? Answer parts a and b. Assume a significance level of alphaequals0.05. Group Count Mean Median StdDev North 28 1612.31 1612 125.97 South 33 1592.56 1575...