1) A poll is planned to determine what proportion of all students favor an increase in fees to support a new track and field stadium. A questionnaire will be published and the first 1000 completed questionnaires will be analyzed. Which of the following errors will be associated with the sample?
A. Errors due to interviewer bias and selection bias
B. Sampling errors only
C. Only non-sampling errors
D. Sampling errors and errors due to selection bias
2) A recent study of breast cancer revealed that 13% of the women in the sample used antibiotics more than 500 days in their lifetime. Further, 79% of these “heavy antibiotics users” developed breast cancer. According to the American Cancer Society, one in twelve women will develop breast cancer at some time in her life. Of the numbers mentioned, which are parameters?
A. 13% and one in twelve
B. 79% and one in twelve
C. 79% and 500 days
D. 13% and 79%
3) What is the difference between probability sampling and simple random sampling?
A. Probability sampling is a type of simple random sample.
B. In probability sampling each item has an identical chance of being chosen.
C. Simple random sampling is a type of probability sampling.
D. There is no difference.
4) Which of the following is an example of statistical inference?
A. Calculating the mean number of fruit trees damaged by Mediterranean fruit flies in California last year.
B. Calculating the amount of fly spray needed for your orchard next season.
C. Calculating the mean age of patients discharged from hospitals in New York State in 1997.
D. Counting the number of patients who file malpractice suits after being discharged from hospitals in New York State.
5) Which of the following statements is false?
A. A summary measure calculated from some of the items of interest is a statistic.
B. Statistical inference is the process of making a prediction based on only a small piece of information.
C. The main goal of descriptive statistics is to estimate characteristics of populations.
D. A summary measure calculated from all items of interest is a parameter.
6) Which of the following is NOT a characteristic of an ideal statistician?
A. Communicates well (both written and oral)
B. Can deal with imperfect information
C. Adapts answers to client desires
D. Technically current (e.g. software)
7) If terms such as positive, negative, more than, and less than, are used, then these hypotheses are_________.
A. alternative hypotheses
B. nondirectional hypotheses
C. null hypotheses
D. directional hypotheses
8) The manipulation of the independent variable is known as the ________.
B. experimental test
9) Name the item that is NOT a recognized survey guideline.
B. quality control
C. ability to find friendly survey respondents
D. pilot or beta test
10) Which of these is NOT an acceptable type of survey question?
A. ranking questions
B. leading question
D. Likert scale
11) Which of these is NOT an acceptable type of survey question?
A. Closed ended
B. Prejudicial or biased questions
C. Fill in the blank
D. Open ended
12) Which of the following is NOT an ethical concern for the statistical researcher?
A. Use of sound methodology
B. Monetary compensation
C. Informed consent
D. Protection of confidentiality
13) Which of the following is NOT an ethical concern for the statistical researcher?
A. Maintain data accuracy
B. Conceal financial support
C. Accurate reporting of procedures
D. Accepted procedures are followed
14) Which of the following is not an ethical concern for the statistical researcher?
A. Inhumane treatment of animals
B. Cite sources
C. Manipulation of data
D. Privacy of privacy
15) The average score for a class of 30 students was 75. The 20 male students in the class averaged 70. The 10 female students in the class averaged
Textbook PriceNumber of Textbooks
$25 to $352
35 to 4516
45 to 555
55 to 657
65 to 7520
Estimate the standard deviation of the price of a textbook.
17) A supermarket has determined that daily demand for eggs has a bell-shaped distribution, with a mean of 55 cartons and a standard deviation of six cartons. If the supermarket begins each morning with a stock of 61 cartons of eggs, approximately what percentage of days will there be a surplus of eggs?
18) Which measurement uses absolute values?
A. ordinal scale
B. harmonic scale
C. ratio correct
D. interval scale
19) Identify the scale which has no meaningful zero.
20) Which of these measurement scales has a rank order associated with its use?
21) Ten bolts were selected randomly from a production line and the diameter of each was measured. Why do these diameters not have a binomial distribution?
A. The diameters of the bolts are not independent of one another.
B. Diameter is a continuous random variable.
C. They have equal probability of success.
D. They do have a binomial distribution.
22) The Information Commons in the main library has 150 personal computers. The probability that any one of them will require repair on a given day is 0.02. To find the probability that exactly 25 of the computers will require repair, one would use what type of probability distribution?
A. Poisson distribution
B. Normal distribution
C. Binomial distribution
D. Hypergeometric distribution
23) Which of the following cannot generate a Poisson distribution?
A. The number of customers arriving at an ATM in a minute
B. The number of people at a movie theatre on Friday evening
C. The number of defects in a new automobile
D. The number of goals in the World Cup soccer game
24) Which of these parameters associated with a binomial experiment will produce a probability distribution with the smallest standard deviation; given n is the same for each situation?
A. p = 0.4
B. p = 0.5
C. p = 0.3
D. (1- p) = 0.1.
A popular restaurant recently asked 300 customers how may times per month they ate steak for dinner. The results were used to build the following probability distribution:
x01234 or more
What is the probability that revenues from pizza slice sales will be greater than $1.00 per customer?
26) Trudy Jones recently completed her certification examination and learned that her z-score was –2.5. The examining board also informed her that a failure to pass would be all scores that were 1 or more standard deviations below the mean and that those with scores higher than 2 standar
d deviations above the mean would receive a special commendation award. Trudy can, therefore, conclude that she
A. needs more data to determine if she passed the exam
B. failed the exam
C. passed the exam and will receive a special commendation award
D. passed the exam, but no commendation award is forthcoming
27) A random variable follows the student’s t distribution. The probability that it will be positive is
C. less than 0.50.
28) The standard error of the sample mean is equal to 5 when n=25. If the sample size increases by a factor of four, how will the standard error change?
A. It will be cut in half
B. It will double
C. It will be cut to ¼ of 5
D. It will quadruple
29) The use of the student’s t distribution requires which of the following assumptions?
A. The population variance is known
B. The sample size is greater than 30
C. The population is normal
D. The sample is drawn from a positively skewed distribution
30) A random sample of 25 observations is selected from a normally distributed population. The sample variance is 10. In the 95% confidence interval for the population variance, the upper limit will be:
A study of 200 insomniacs paid for by the Serta Mattress Company found that the average insomniac counted 350 sheep before falling asleep, with a standard deviation of 120. An insomniac is a person who has difficulty falling asleep. Some useful numbers might be:
Out of the 200 insomniacs, 98 reported regularly watching The Late Show with David Letterman before they began to count sheep.Calculate the margin of error for a 78% confidence interval of the true proportion of insomniacs who regularly watch David Letterman before counting sheep.
32) Ceteris paribus, which is narrower, a 95% confidence interval with n=100 or a 99% confidence interval with n=30?
A. The 99% confidence interval
B. Need the margin of error to tell
C. They are the same width.
D. The 95% confidence interval
33) When the results of a process are either defective or acceptable, the charts used for SPC are called
A. control charts for attributes.
B. control charts for variables.
C. control charts for in control process.
D. control charts for out of control process.
34) To tell if the standard deviation of a process has changed, the control charts used are
A. p and R charts.
B. S and x bar charts.
C. R and S charts.
D. x bar and p charts.
35) When the only sources of variation in a production process are caused by chance, the process is said to be
A. out of control but in balance.
B. out of control.
C. under control.
D. out of balance but under control.