cornflakes; after two weeks their low-density-lipoprotein cholesterol
levels were recorded. Each man was then switched to the alternative diet.
After a second two-week period, the LDL cholesterol level of each per-
son was recorded again (Table E7.6). Test to compare the means LDL
cholesterol level. Name the test and state clearly your null and alterna-
tive hypotheses and choice of test size.TABLE E7.6
LDL (mmol/L)
Subject Cornflakes Oat Bran
1 4.61 3.84
2 6.42 5.57
3 5.40 5.85
4 4.54 4.80
5 3.98 3.68
6 3.82 2.96
7 5.01 4.41
8 4.34 3.72
9 3.80 3.49
10 4.56 3.84
11 5.35 5.26
12 3.89 3.73
13 2.25 1.84
14 4.24 4.147.7 Data in epidemiologic studies are sometimes self-reported. Screening
data from the hypertension detection and follow-up program in Minne-
apolis, Minnesota (1973–1974) provided an opportunity to evaluate the
accuracy of self-reported height and weight (see Example 7.4). Table 7.3
gives the percent discrepancy between self-reported and measured height:
x¼self-reported heightmeasured height
measured height100%
Example 7.4 was focused on the sample of men with a high school edu-
cation. Using the same procedure, investigate the di¤erence between self-
reported height and measured height among:
(a) Men with a college education.
(b)Women with a high school education.
(c) Women with a college education.
In each case, name the test and state clearly your null and alternative
hypotheses and choice of test size. Also, compare the mean di¤erence in
percent discrepancy between:EXERCISES 273