AP Statistics – Review First Semester Name ___________________________________
1. Given the following scores on an attitude test for a sample of 18 students: {154, 109, 137, 115, 152,
140, 154, 178, 101, 103, 126, 126, 137, 165, 165, 129, 200, 148}. Make a stemplot of these data.
Are there any outliers? About where is the center of the distribution? What is the spread of the
scores (ignoring any outliers)?
2. In a right-skewed distribution, arrange mean, median and mode in smallest to largest order.
3. Given the following data: 20 25 25 27 28 31 33 34 36 37 44 50 59 85 86
Would mean or median be the better measure for center and why?
Calculate the IQR (the middle 50%)
Test for outliers.
Make a modified boxplot.
Which measures for center and spread are greatly influenced by outliers?
4. Age (months) 36 48 51 54 57 60
Height (cm) 86 90 91 93 94 95
Find the LSRL. Interpret the slope in the context of the problem.
NOTE: understand the difference (effect) of outliers and influential observations. (Outliers usually have large residuals/they do not have as much effect on the LSRL. Influential observations have greater effect on the LSRL and can increase the correlation. They tend to have small residuals)
5.
(a) What is the smallest cirumference? How many people in the study have this circumference?
(b) What is the highest strength? How many people have this strength?
(c) How many people have strength of 40?
(d) Describe the association.
6. Gas consumption is based on average number of heating degree days each day for a month. Degree days has a mean of 22.31 and standard deviation of 17.74. Gas consumption has a mean of 5.31 and standard deviation of 3.37. The correlation is .995. Find the least squares regression line to show the relationship between degree days and gas consumption.
7. Speed 20 60 50 60 60
MPG 24 28 30 28 24
Graph the scatterplot and graph the residuals (on your calculator if you choose). Interpret the residual plot.
8. What is the difference between an experiment and an observational study?
9.
(i) What is the probability that a person chosen in female or takes the bus?
(ii) What is the probability that a person is male, given that they take personal transportation?
(iii) What is the probability that a person is a male who rides with someone?
10. What is a voluntary response sample?
11. What is a simple random sample?
12. Scores on an aptitude test are normally distributed with a mean of 150 and a standard deviation of 23. What score would a person need to fall in the top 2%?
13. Suppose P(X) = .35 and P(Y) = .40. If P(X|Y) =.28, what is P(Y|X)?
14. What is a stratified random sample?
15. What is the difference in a control group and an experimental group?
16. Can an experiment give good evidence for causation?
17. Give the three principals of experimental design.
18. What is blocking?
19. Review undercoverage, nonresponse, response bias, and wording of questions
20. Which is more likely, getting 50 heads on 100 flips or getting 500 heads on 1000 flips?
21. Make a probability distribution table for the number of tails when flipping 3 coins. What is the probability of getting at least one tail?
22. Transform the given data to achieve linearity and find the resulting LSRL
1978 63042
1979 226260
1980 907075
1981 2826095
Review transformations to achieve linearity. Exponential” LSRL will be log y = a + bx OR ln y = a + bx. Power: LSRL will be log y = a + b log x OR ln y = a + b ln x.
23. Make a segmented bar graph showing the percent of students who smoke and the percent who don’t smoke based on parental smoking behavior.
Student smokes Student doesn’t smoke
Both parents smoke 400 1380
One parent smokes 416 1823
Neither parent smokes 188 1168
24. Salary of computer technicians in the US is normally distributed with mean $32,550 and standard deviation $2000. Find the probability that a randomly selected computer technician will earn more than $35,000.
25. The average score on the Math SAT is 650 with standard deviation of 60. If each score increases by 10%, give the new mean and standard deviation.
26. Given the following distributions for X and Y:
X 1 2 3 Y 1 2 3
P(X) .1 ? ? P(Y) ? ? .2
X and Y are independent and two joint probabilities are P(X = 1, Y = 1) = .025 and P(X = 3, Y = 3) = .08. What is P(X = 2, Y = 2)?
27. It is estimated that 30% of all cars parked in a metered lot receive tickets for meter violations. In a
random sample of 5 cars parked in this lot, what is the probability that at least one receives a
parking ticket?
28. A poll shows that 65% of the registered voters in a country are Democrats and the rest are
Republicans. Suppose that 60% of the Democrats and 50% of the Republicans support a bond
Issue. What is the probability that a registered voter supports the bond issue? What is the
probability that a voter chosen at random who turns out to support the bond issue is a Democrat?
29. What is sampling error?
30. Suppose that for a certain Caribbean island in any 3-year period the probability of a major
hurricane is 0.25, the probability of flooding is 0.44, and the probability of both a hurricane and
flooding is 0.22. What is the probability of flooding given that there is a hurricane?
GOOD LUCK J