Question

a sample of blood - pressure measurements is taken from a data set and those values (mm hg) are listed below. the values are matched so that subjects each have systolic and diastolic measurements. find the mean and median for each of the two samples and then compare the two sets of results. are the measures of center the best statistics to use with these data? what else might be better? systolic: 136 145 99 100 140 134 155 122 111 151 diastolic: 76 66 80 65 69 58 85 51 77 54 what else might be better? a. because the data are matched, it would make more sense to investigate whether there is an association or correlation between the two blood - pressures. b. because the data are matched, it would make more sense to investigate any outliers that do not fit the pattern of the other observations. c. since measures of center are appropriate, there would not be any better statistic to use in comparing the data sets. d. since measures of center would not be appropriate, it would make more sense to talk about the minimum and maximum values for each data set.

Explanation:

Step1: Recall measure - of - center concepts

The measures of center are mean and median. When data is matched (paired), we can consider if there is an association between the two variables (systolic and diastolic blood pressures here). If there is an association, it makes sense to check for outliers and see if they affect the relationship.

Step2: Analyze options

Option A is correct because when data is matched, we should investigate for outliers that can distort the relationship or pattern between the two blood - pressure measurements. Options B and C are incorrect as measures of center (mean and median) are still relevant for comparing the two data sets even if they are matched. Option D is incorrect as minimum and maximum values are not the best way to compare the data sets when we are interested in the central tendency and the relationship between the paired data.

Answer:

A. Because the data are matched, it would make more sense to investigate whether there is an association or correlation between the two blood pressures.