Question

TABLE: You have been asked to find the relationship between the dosage of a medication and its effect on blood pressure Amount of medication() Blood Pressure (y) 100 1. Find the correlation coefficient (a) 0.98 (b)-0.52 (c) 0,07 (d) 0.54 (6)0,95 2. What can you conclude (ie strong vs. weak, positive vs negative correlation) (a) Strong negative (b) Waak negative (e) no correlation (e) Strong positive (d) weak positive 3. (d)5.5 (e) 9 Find the slope(m) of the regression line: (b) 55 (c) 0,5 Find the y-intercept: b: (a) 84 (b) 86 (c) 102 4. (d) 131 (e) 160 5. For 10% level of significance (2 tail a), find the critical value. (a) +2.353 (b) 11.886 (c) 2.920 (d) 14.303 (0) 21.638

Answer 1

Answer Date: 08/08/2019 1) The correlation coefficient is, First, compute the calculation table then find correlation coefficient. The calculation table is, X2 XY Y 100 90 1 Y2 100000 8100 3600 2500 24200 4 16 36 56 60 180 240 300 720 50 300 Total

The correlation coefficient is, 1 = nE xv-EXSv) Vr (Ex2)-(Ex} \n(Sy2)-(»)? 4x720 - 12 x 300 14x56 – (12) 4x 24200 - (300)2 = -0.98 The correlation coefficient is -0.98. The answer is a). The correlation coefficient between amount of medication and blood pressure is -0.98 conclude there is a strong negative relationship between amount of medication and blood pressure. The answer is a 3)

The slop of the regression line is, m = n (8x2)-(2x) 4x720 - 12 x 300 4x 56 -(12) = -9 The slop of the regression line is -9. The answer is a. 4)

The y-intercept is, b = - B, xĨ INI - B x _300 -(-9)*** = 102 The y-intercept is 102. The answer is G. The t critical value for the 95% confidence is, The sample size is small and two-tailed test. Look in the column headed a = 0.10 and the row headed in the t distribution table by using degree of freedom is,

d.f.=n-2 = 4-2 = 2 The t critical value for the 95% confidence is 2.9201. The answer is C