Drawing Inferences (Two Sample)

STEP-BY-STEP explanation

1.A vicious debate between behaviorists and traditional medical doctors concerns the merits of using the stimulant Ritalin in treating childhood hyperactivity. A large group of hyperactive children in an urban school system was randomly assigned to either a behavior modification program or a drug therapy program. The dependent variable measured is the children's' hyperactivity score after 18 weeks of treatment. Use the data shown directly below to determine if there is a significant difference on these children's' hyperactivity scores.

Behavior

22, 24, 27, 18, 21, 19, 18, 17, 14, 17,

20, 16, 13, 20, 16, 12, 14, 22, 23, 18

Drug

26,32, 31, 20, 34, 36, 22, 29, 27, 25,

24, 32, 24, 20, 32, 32, 29, 27, 33, 30

2. Based upon the results of a manual dexterity test, two matched groups of BSIT Automotive Major college students were formed. One group of students was asked to drive an automobile simulator after having consumed three bottles of beer in one hour. The second group of students drove the same simulator after consuming three bottles of non-alcoholic beer in the same time period. The numbers of errors per minute were recorded in the simulator. Is there a significant decrease in the errors per minute recording of the non-alcoholic group? Use an alpha level of 0.01.

Alcohol = 6,4,9,3,15,5,9,7,6,8

Non - alcohol = 5,5,6,0,8,2,4,2,8,4

3. The Dean of the College of Industrial Technology and Engineering wants to investigate whether there is any difference between the scores of the students in mathematics for those who attend classes during the day and those who work during the day and attend evening classes. Records of both day and evening classes revealed that

Student Mean Score SD No.of samples taken

DAY 90 12 53

EVENING 94 15 46

Use the 6 step procedure and arrive at a decision from a 0.05 level of significance.