Question

In a study on the healing process of a cut, researchers observed the time required to completely heal the cut. Ten rats were randomly divided into two groups of five. No treatment was done to one group and a medical treatment was given to the other group. The time spent (in hours) to completely heal the cut for each rat is given below. Control: 23, 27, 30, 26, 31Treatment: 21, 22, 18, 24, 30 Test if the mean duration of healing can be reduced by the medical treatment What is the value of the test statistic (round off to second decimal place)

Answer 1

0.44

Explanation:

Given the data:

Control: 23, 27, 30, 26, 31

Treatment: 21, 22, 18, 24, 30

The mean and variance using calculator :

Control :

Mean, x1 = 27.4

Variance, s1 = 10.3

n1 = 5

Treatment :

x2 = 23

s² = 20

H0 : μ1 = μ2

H0 : μ1 > μ2

The test statistic :

(x1 - x2) / √(s1²/n1) + (s2²/n2)

(27.4 - 23) / √(10.3²/5) + (20²/5)

4.4 / 10.060715

Test statistic = 0.437

Test statistic = 0.44