7.2.12 After surgery a patient’s blood volume is often depleted. In one study, the total circulating volume of blood plasma was measured for each patient immediate- ly after surgery. After infusion of a “plasma expander” into the bloodstream, the plasma volume was measured again and the increase in plasma volume (ml) was calcu- lated. Two of the plasma expanders used were albumin (25 patients) and polygelatin (14 patients). The accompa- nying table reports the increase in plasma volume.13 [Note: Formula (6.7.1) yields 33.6 df.]

 

Use a t test to compare the mean increase in plasma volume under the two treatments. Let a = 0.01.

 

 

 

 

                         ALBUMIN POLYGELATIN

 

a = 0.10, and the P-value is 0.07. For each of the follow-

 

ing statements, say whether the statement is true or false and explain why.

 

(a)     We reject H0 with a = 0.10.

 

(b)     We have significant evidence for HA with a = 0.10.

 

(c)     We would reject H0 if a were 0.05.

 

(d)     We do not have significant evidence for HA with

 

a  = 0.05.

(e)     The probability that Y1 is greater than Y2 is 0.07