test the hypothesis that two nominal variables are related
1. (1) Which of the following can be used to test the hypothesis that two nominal variables are related?
Answer
a contingency table.
a chi-square table.
an ANOVA table.
a scatter diagram.
7. (2) On a very hot summer day, 5 percent of the production employees at Midland States Steel are absent from work. The production employees are randomly selected for a special in-depth study on absenteeism. What is the probability of randomly selecting 10 production employees on a hot summer day and finding that none of them are absent?
Answer
0.0
02
0.344
0.599
0.1
00
8. (3) A farmer who grows genetically engineered corn is experiencing trouble with corn borers. A random check of 5,000 ears revealed the following: many of the ears contained no borers. Some ears had one borer; a few had two borers; and so on. The distribution of the number of borers per ear approximated the Poisson distribution. The farmer counted 3,500 borers in the 5,000 ears. What is the probability that an ear of corn selected at random will contain no borers?
Answer
0.3476
0.4966
1.0
00
0.0631
10. (4) David’s gasoline station offers 4 cents off per gallon if the customer pays in cash and does not use a credit card. Past evidence indicates that 40% of all customers pay in cash. During a one-hour period twenty-five customers buy gasoline at this station.
What is the probability that no more than twenty pay in cash?
Answer
0.0
0.1
0.9
1.0
11. (5) A tire manufacturer advertises, “the median life of our new all-season radial tire is 50,000 miles. An immediate adjustment will be made on any tire that does not last 50,000 miles.” You purchased four of these tires. What is the probability that all four tires will wear out before traveling 50,000 miles?
Answer
1/10 or 0.10
¼ or 0.25
1/64 or 0.0156
1/16 or 0.0625
13. (6) If two events are independent, then their joint probability is
Answer
computed with the special rule of addition
computed with the special rule of multiplication
computed with the general rule of multiplication
computed with Bayes theorem
14. (7) A sample of the paramedical fees charged by clinics revealed these amounts: $55, $49, $50, $45,
$52
and $55. What is the median charge?
Answer
$47.50
$51.00
$52.00
$55.00
15. (8) The following are the weekly amounts of welfare payments made by the federal government to a sample of six families: $139, $136, $130, $136,
$14
7 and $136. What is the range?
Answer
$0
$14
$52
$17
16. (9) A disadvantage of using an arithmetic mean to summarize a set of data is
Answer
The arithmetic mean sometimes has two values.
It can be used for interval and ratio data.
It is always different from the median.
It can be biased by one or two extremely small or large values.
17. (10) What level of measurement is the price of an admission ticket to a movie theater?
Answer
Nominal
Ordinal
Interval
Ratio
18. (11) A survey includes a question regarding marital status that has the following responses: single, married, divorced, separated or widowed. What is the scale of measurement for this question?
Answer
Ratio
Interval
Ordinal
Nominal
20. (12) What is the variable used to predict the value of another called?
Answer
Independent variable
Dependent variable
Correlation variable
Variable of determination
22. (13) Which symbol is a test statistic used to test a hypothesis about a population mean?
Answer
α
β
μ
z
23. (14) What is a Type II error?
Answer
Accepting a false null hypothesis
Rejecting a false null hypothesis
Accepting a false alternate hypothesis
Rejecting a false alternate hypothesis
24. (15) What is another name for the alternate hypothesis?
Answer
Null hypothesis
Hypothesis of no difference
Rejected hypothesis
Research hypothesis
26. (16) What is the difference between a sample mean and the population mean called?
Answer
Standard error of the mean
Sampling error
Interval estimate
Point estimate
27. (17) A survey of an urban university (population of 25,450) showed that 750 of 1100 students sampled attended a home football game during the season. Using the 90% level of confidence, what is the confidence interval for the proportion of students attending a football game?
Answer
[0.7510, 0.8290]
[0.6620, 0.6980]
[0.6659, 0.6941]
[0.6795, 0.6805]
28. (18) How is the t distribution similar to the standard z distribution?
Answer
Both are continuous distribution
Both are bell-shaped
Both are families of distributions
A and B
29. (19) A sample of 50 is selected from a known population of 250 elements. The population standard deviation is 15. Using the finite correction factor, what is the standard error of the sample means?
Answer
2.89
1.90
2.12
Cannot be determined
30. (20) Administering the same test to a group of 15 students and a second group of 15 students to see which group scores higher is an example of
Answer
a one sample test of means.
a two sample test of means.
a paired t-test.
a test of proportions.
31. (21) Of 250 adults who tried a new multi-grain cereal, “Wow!”, 187 rated it excellent; of 100 children sampled, 66 rated it excellent. What test statistic should we use?
Answer
z-statistic
Right one-tailed test
Left one-tailed test
Two-tailed test
33. (22) The weekly mean income of a group of executives is $1000 and the standard deviation of this group is $100. The distribution is normal. What percent of the executives have an income of $925 or less?
Answer
About 15%
About 85%
About 50%
About 23%
34.(23) A random variable from an experiment where outcomes are normally distributed
Answer
can have any value between – ∞ and + ∞.
can have only a few discrete values.
can have a mean of 0 and a standard deviation of 1.
can have no values.
35. (24) Which of the following is true in a normal distribution?
Answer
Mean equals the mode and the median
Mode equals the median
Mean divides the distribution into two equal parts
All of the above are correct
36. (25) What does the interquartile range describe?
Answer
The lower 50% of the observations
The middle 50% of the observations
The upper 50% of the observations
The lower 25% and the upper 25% of the observations
