AP STATS Barrons Style Comprehensive Test Review:
(Topics 1-11) 50 Points [UPDATED: 12/15/12]
ALL QUESTIONS ARE WORTH 1 POINT
1. The regression expression equation is 3x+b and has the coordinates of (2,5) If x-bar and y-bar is the
sample mean, what is the value of y bar?
2. If the standard deviation of a set of observations is 0, you can conclude what?
3. If the average value is close to the standard deviation in value how will it be skewed? Or will it be
skewed at all?
4. Say you score 100 on a test with a standard deviation of 2.7 and a mean of 100.837, what is the
probability that you scored higher than your peers?
5. Explain Sampling Error and Sources of Bias and how they are related to each other.
6. What would a graph that has an R value of 1 look like? -1?
7. True or False? The sum and thus the mean of the residuals is always zero. No, Explain.
8. What are the possible values of the r correlation coefficient? (range)
9. According to empirical formula, what is the % in the range of -2 - 0 (z score)
10. What is the definition of independent events? Give a real life example.
11. Use the numbers 10, 15, 100, 12, 19, and 38 to find the mean, SD, range, and IQR of the numbers.
12. A company employs both men and women in its secretarial and executive positions. In reports filed with
the government, the company shows that the percentage of female employees who receive raises is higher
than the percentage of male employees who receive raises, and that the percentage of male executives
who receive raises is higher than the percentage of female executives who receive raises. Is this possible?
13. What’s the difference between observational studies and experiments? Which can you draw causation
from and why?
14. If a guy who slacks off has a 60 percent chance of doing his homework, what is the probability that he
will not do his homework on the 6th day?
15. What are characteristics of a normal curve? Explain in depth.
16. Suppose the height of policemen is 71 inches with a standard deviation of 4 inches, while the average
for policewomen is 66 inches with a standard deviation of 3 inches i. If a committee looks at all ways of
pairing up one male with one female officer, what will be the mean and standard deviation for the difference
in heights for the set of possible partners?
17. Given that 58% of all gold dealers believe next year will be a good one to speculate in South African
gold coins, in a simple random sample of 150 dealers, what is probability that between 55% and 60%
believe that it will be a good year to speculate?
18. What is the purpose of blocking?
19. IF blocking was employed what difficulties could there be in drawing inferences?
20. What is the best way to sample populations?
21. Suppose 15% of the employees in a factory are drug users. What is the probability that there will be
exactly two drug users in a randomly chosen 7 person working group?
22. Two dice are thrown on the table. What I the probability the sum will be 5?
23-26 Use the following data table to answer the questions: (WORTH 3 POINTS)
AGE
NUMBER OF SURVIVORS
0
20,000
20
19,875
40
19,245
70
13,222
What is the probability that a 40-year old will survive to be 70?
27. Explain in a detailed process how to calculate SSRESID? And SSTO
28. What is the formula for calculating confidence intervals?
29. What percent of the total population is represented between the z scores -1.7- .3
30. What is standard deviation?
31. Is the median affected when outliers are manipulated?
32.
x
P(x)
1
?
2
.2
3
.3
4
?
y
P(y)
1
.4
2
?
3
.1
If x and y are independent and the joint probability P (x=1, y=2) =.1 what is p(x=4)?
33. Each of the 29 NBA teams has 12 players. A sample of 58 players is to be chosen as follows. Each
team will be asked to place 12 cards with its player chosen as follows. Each team will be asked to place 12
cards with its player’s names into a hat and randomly draw out two names. The two names from each team
will be combined to make up the sample. Will this method result in a simple random sample of the 348
basketball players?
34. To find out the average occupancy size of student – rented apartments, a researcher picks up a simple
random sample of 100 such apartments. Even after one follow up visit, the interviewer is unable to make
contact with anyone in 27 of these apartments. Concerned about nonresponse bias, the researcher
chooses another simple random sample and instructs the interviewer to continue this procedure until
contact is made with someone in a total of 100 apartments. The average occupancy size in the final 100apartment sample is 2.78. Is this estimate too low or high?
35.
1. Although 18% of the student body is minorities, in a random sample of 20 students, 5 are
minorities.
2. In a survey about sexual habits, an embarrassed student deliberately gives the wrong answers.
3. A surveyor mistakenly records answers to one question in the wrong space.
Which of these is true?
36. If you were to sample a population by telephone what factor prohibits you from drawing accurate
conclusions?
37. If there is a 27 percent chance of lightining, 33 percent chance of a tornado occuring, and a 10 percent
chance of both, what is the probability that a thunderstorm occurs given that there is a tornado?
38. A coffee machine can be adjusted to deliver any fixed number of ounces of coffee. If the machine has a
standard deviation in delivery equal to .4 of an ounce, what should be the mean setting so that the 8 ounce
cup will overflow only .5% of the time.
39. A factory dumps an average of 2.43 tons of pollutants into a river every week. If the standard deviation
is .88 tons, what is the probability that in a week more than 3 tons are dumped?
40. When the data is skewed right is the mean greater than the median or the other way around?
41. What is under coverage bias/nonresponse bias?
42. 75% families pay $75. And 15% families pay $150. Find the mean and standard deviation of the data
43. There is a .43 chance of you beating your opponent in chess, what is the probability you beat him 4 or
more times
44. Out of a group of 13 various colored cacti, how many groups can you make with 6 of them.
45-47. WORTH 3 POINTS
769 Men Survey
HAIR LOSS
PATTERN
NONE
FRONTAL
VERTEX
Less than 25
100
24
43
Body Mass Index
25-28
208
30
66
More than 28
158
35
105
IS HAIR LOSS PATTERN RELATED TO BODY MASS INDEX?
48. How would you determine what percentile you are if you score (x) on a test given standard deviation,
and mean?
49. What is percentile given z-score 2.76?
50. What is the purpose of the various types of sampling? Give examples of 3 and explain.