(b)If it is known that the average body mass index for middle-aged men
who do not develop diabetes is 24.0 kg/m^2 , what can you say about
the relationship between body mass index and diabetes in middle-
aged men?4.29 A study was undertaken to clarify the relationship between heart disease
and occupational carbon disulfide exposure along with another impor-
tant factor, elevated diastolic blood pressure (DBP), in a data set ob-
tained from a 10-year prospective follow-up of two cohorts of over 340
male industrial workers in Finland. Carbon disulfide is an industrial
solvent that is used all over the world in the production of viscose rayon
fibers. Table E4.29 gives the mean and standard deviation (SD) of serum
cholesterol (mg/100 mL) among exposed and nonexposed cohorts, by
diastolic blood pressure (DBP). Compare serum cholesterol levels
between exposed and nonexposed cohorts at each level of DBP by cal-
culating the two 95% confidence intervals for the means (exposed and
nonexposed groups).
TABLE E4.29
Exposed Nonexposed
DBP
(mmHg) n Mean SD n Mean SD
< 95 205 220 50 271 221 42
95–100 92 227 57 53 236 46
b 100 20 233 41 10 216 484.30 Refer to the data on cancer of the prostate in Exercise 2.39, and calcu-
late the 95% confidence interval for Pearson’s correlation between age
and the level of serum acid phosphatase.
4.31 Table E4.31 give the net food supply (x, the number of calories per per-
son per day) and the infant mortality rate (y, the number of infant
TABLE E4.31
Country xyCountry xy
Argentina 2730 98.8 Iceland 3160 42.4
Australia 3300 39.1 India 1970 161.6
Austria 2990 87.4 Ireland 3390 69.6
Belgium 3000 83.1 Italy 2510 102.7
Burma 1080 202.1 Japan 2180 60.6
Canada 3070 67.4 Netherlands 3010 37.4
Chile 2240 240.8 New Zealand 3260 32.2
Cuba 2610 116.8 Sweden 3210 43.3
Egypt 2450 162.9 U.K. 3100 55.3
France 2880 66.1 U.S. 3150 53.2
Germany 2960 63.3 Uruguay 2380 94.1184 ESTIMATION OF PARAMETERS