A Clinical Neuropsychologist Develops a New Treatment for Recovery from Head

Multiple Choice

A clinical neuropsychologist develops a new treatment for recovery from head trauma and administers it to one half (randomly selected) of a sample of 50 people.He measures the level of cognitive functioning one month after the trauma and analyses the data in SPSS.The output of a between-participant t-test is shown below: Which of the following statements is true?

A) There are good grounds to suspect that the variances are unequal.
B) We should reject the results of this test due to the unequal variances.
C) Both (a) and (b) .
D) It is not surprising that the cognitive functioning is variable following head trauma so we should pay no attention to unequal variances, especially as the t-test is robust to violation of assumptions.
E) All of the above.