Question

The systolic blood pressure of individuals is thought to be related to both age and weight. For a random sample of 11 men, the following data were obtained Weight (pounds) Systolic Blood pressue Age (years) 149 132 52 173 143 59 184 153 67 194 162 73 211 154 64 196 16B 74 220 137 54 188 61 188 159 65 207 128 46 167 166 72 217 (a) Generate summary statistics, including the mean and standard deviation of each variable. Compute the coefficient of variation for each variable. (Use 2 decimal places.) s CV X 150 2 X 13.63 091 X% X, 6245 ✓ 146 X% X3 195 ✓ 16 X 089 Relative to its mean, which variable has the greatest spread of data values? Which variable has the smallest spread of data values relative to its mean? O X2 X3 CX3, X2 (b) For each pair of variables, generate the correlation coefficient. Compute the corresponding coefficient of determination r. (Use 3 decimal places.) 895 which variable (other than x) has the greatest influence (by itself) on xx? Would you say that both variables x, and X, show a strong influence on x; ? Explain your answer. X; Yes, both have values close to 1. Xx: No, both have values far from 1. XyNo, both have values far from 1.

Answer 1

(a)

	x	s	CV
x1	150.09	13.63	9.08%
x2	62.45	9.11	14.59%
x3	195.00	17.31	8.88%

(b) 94.2%

(e)

	t (df=8)	p-value
b2	3.47	0.008
b3	2.56	0.034

(f)

	confidence interval
	90% lower	90% upper
x2	0.40	1.32
x3	0.09	0.58

(g)

	90% Confidence Interval
Predicted	lower	upper
153.9	150.4	157.4