1. If two lists of numbers have exactly the same mean of 30 and the same standard deviation of 5, then the percentage of numbers between 25 and 35 must be exactly the same for both lists.
(a) True
(b) False
2. If the slope of a regression line is zero, then the correlation coecient is zero. Likewise, if the slope of the line is one, then the correlation coecient is one.
(a) True
(b) False
3. I calculate the residuals from a regression line predicting weight from height. I nd that all the residuals are negative. This is impossible; I must have made a mistake in my calculations.
(a) True
(b) False
4. In drawing a sample from a population, the sampling variability increases with sample size.
(a) True
(b) False
5. A 90% condence interval for a population proportion p is constructed from a random sample of size 500 and is found to be 0:48 0:04. If another random sample of the same size is drawn, the 90% condence interval for p constructed based on this new sample will have a 90% chance of including the value 0.48.
(a) True
(b) False
6. Farmers concerned with the aect of snowfall levels on their crops found that there wasn't sucient evidence of a decrease in crop growth. They based this conclusion on a hypothesis test using = 0:05. They would have made the same decision at = 0:01.
(a) True
(b) False
7. One-way ANOVA provides evidence against the null hypothesis that the population means are all equal when the between-group variation is large compared to the within-group variation.
(a) True
(b) False
8. Consider the following histograms of two data sets (both contains 80 observations): Which of the following statements is (are) true about the two data sets?
(1) Data 1 has a smaller median that data 2.
(2) Data 1 has a larger standard deviation than data 2.
(3) Data 1 has a smaller IQR than data 2.
(4) The range of the two data sets is approximately the same.
(a) (3) only
(b) (1) and (2) only
(c) (1) and (3) only
(d) (1) and (4) only
9. For which of the 4 plots below will you expect the corresponding residual plot to be patternless?
(a) Y1 * X1 only
(b) Y4 * X4 only
(c) Y1 * X1 and Y2 * X2
(d) Y3 * X3 only
(e) Y1 * X1 and Y4 * X4
10. Data were collected within a group of males in an athletic association in BC. Based on this dataset, a regression model was computed to predict weight Y (in kg) from height X (in cm). The model tted was
Y = 0:28X + 27:00:
If intending to predict height from weight using the same dataset, which of the following statements most precisely describes what you can say about the appropriate regression line?
(a) The slope of the regression line would be 0.28.
(b) The slope of the regression line would be 27.00
(c) The slope of the regression line would be positive.
(d) The slope of the regression line would be negative.
(e) The slope of the regression line would be 3.57.
11. A study on the accreditation rate of food-and-drink businesses by the Better Business Bureau obtained a sample from the telephone directory's Yellow Page listings of food-and-drink businesses in Greater Vancouver. The investigator of this study rst drew a simple random sample of 4 cities in Greater Vancouver. Then within each selected city, he randomly sampled 50 businesses. For various reasons, the study got no response from 39.5% of the 200 businesses chosen. Interviews were completed with 121 businesses that responded.
(1) The population of interest to the investigator is
(a) all food-and-drink businesses in Greater Vancouver that are listed under the telephone directory's Yellow Page.
(b) all food-and-drink businesses in Greater Vancouver.
(c) the 200 businesses that were chosen by the investigator.
(d) the 121 businesses that responded.
(2) What is the statistic?
(a) The proportion of all food-and-drink businesses in Greater Vancouver listed under the telephone directory's Yellow Pages that are accredited by the Better Business Bureau.
(b) The proportion of all food-and-drink businesses in Greater Vancouver that are accredited by the Better Business Bureau.
(c) The proportion of the 200 businesses sampled by the investigator that are accredited by the Better Business Bureau.
(d) The proportion of the 121 businesses that responded which are accredited by the Better Business Bureau.
(3) The sampling method that the investigator employed in choosing the 200 businesses is
(a) simple random sampling
(b) stratied random sampling
(c) multistage sampling
(d) systematic sampling
12. An education researcher was interested in examining the eect of teaching method and the eect of the particular teacher on students' scores on a reading test. In a study, there were two dierent teachers (Juliana and John) and three dierent teaching methods (method A, method B, and method C). Two hundred and fty students were randomly assigned to a teaching method and teacher.
(1) For this experiment, identify the response variable.
(a) Teaching method
(b) The education researcher
(c) Teacher
(d) Score on reading test
(2) Identify the factors in the study.
(a) Teaching method and teacher
(b) Juliana and John
(c) Juliana and method A, Juliana and method B, Juliana and method C, John and method A, John and method B, John and method C
(d) Method A, method B and method C
(3) Which of the following is a correct statement about the study?
(a) This is a completely randomized design.
(b) This study uses a placebo.
(c) This study cannot justify a cause-and-eect relationship.
(d) All of the above.
(4) The researcher wants to compare the scores on the reading test between dierent treatment groups. Which of the following four display(s) is (are) appropriate for the comparison?
(1) contingency table
(2) side-by-side boxplots
(3) scatterplot
(4) bar graph
(a) (2) only
(b) (2) and (4) only
(c) (1) and (3) only
(d) (2), (3) and (4) only
13. Consider sampling with replacement from a large population of people. Within the population, the variance of IQ is denoted 2. The sample size is n; and the mean of the sample IQs is found. The variance of this sample mean is
(a) 2 provided n is large.
(b) 2 for any value of n:
(c) 2=n provided n is large.
(d) 2=n for any value of n:
(e) 2= n for any value of n:
The next four questions (Q14 - Q17) refer to the following situation.
A politician must decide whether or not to run the next local election. He would be inclined to do so if more than 30% of the voters would favour his candidacy. The results of a poll of 225 local citizens showed that 81 favour the politician. Should the politician decide to run the election based on the results of this survey? Carry out an appropriate hypothesis test at = 0:01 to answer this question.
14. What is the parameter of interest?
(a) 30%
(b) The proportion of citizens who favor the politician among the poll of 225 local citizens.
(c) 36%
(d) The proportion of all citizens who favor the politician.
15. Denote p as the parameter of interest. What are the correct hypotheses?
(a) H0 : p = 0:36 v.s HA : p > 0:36
(b) H0 : p = 0:30 v.s HA : p 6= 0:30
(c) H0 : p = 0:30 v.s HA : p > 0:30