1) The main purpose of descriptive statistics is to
A. summarize data in a useful and informative manner
B. make inferences about a population
C. determine if the data adequately represents the population
D. gather or collect data
2) The general process of gathering, organizing, summarizing,analyzing, and interpreting data is called
B. descriptive statistics
C. inferential statistics
D. levels of measurement
3) The performance of personal and business investments is measuredas a percentage, return on investment. What type of variable isreturn on investment?
4) What type of variable is the number of robberies reported inyour city?
5) What level of measurement is the number of auto accidentsreported in a given month?
6) The names of the positions in a corporation, such as chiefoperating officer or controller, are examples of what level ofmeasurement?
7) Shoe sizes, such as 7B, 10D, and 12EEE, are examples of whatlevel of measurement?
8) Monthly commissions of first-year insurance brokers are $1,270,$1,310, $1,680, $1,380, $1,410, $1,570, $1,180, and $1,420. Thesefigures are referred to as
A. a histogram
B. raw data
C. frequency distribution
D. frequency polygon
9) A small sample of computer operators shows monthly incomes of$1,950, $1,775, $2,060, $1,840, $1,795, $1,890, $1,925, and $1,810.What are these ungrouped numbers called?
B. Class limits
C. Class frequencies
D. Raw data
10) The sum of the deviations of each data value from this measureof central location will always be 0
D. Standard deviation
11) For any data set, which measures of central location have onlyone value?
A. Mode and median
B. Mode and mean
C. Mode and standard deviation
D. Mean and median
12) A sample of single persons receiving social security paymentsrevealed these monthly benefits: $826, $699, $1,087, $880, $839,and $965. How many observations are below the median?
13) A dot plot shows
A. the general shape of a distribution
B. the mean, median, and mode
C. the relationship between two variables
D. the interquartile range
14) The test scores for a class of 147 students are computed. Whatis the location of the test score associated with the thirdquartile?
15) The National Center for Health Statistics reported that ofevery 883 deaths in recent years, 24 resulted from an automobileaccident, 182 from cancer, and 333 from heart disease. Using therelative frequency approach, what is the probability that aparticular death is due to an automobile accident?
A. 24/883 or 0.027
B. 539/883 or 0.610
C. 24/333 or 0.072
D. 182/883 or 0.206
16) If two events A and B are mutually exclusive, what does thespecial rule of addition state?
A. P(A or B) = P(A) + P(B)
B. P(A and B) = P(A) + P(B)
C. P(A and/or B) = P(A) + P(B)
D. P(A or B) = P(A) – P(B)
17) A listing of all possible outcomes of an experiment and theircorresponding probability of occurrence is called a
A. random variable
B. probability distribution
C. subjective probability
D. frequency distribution
18) The shape of any uniform probability distribution is
A. negatively skewed
B. positively skewed
D. bell shaped
19) The mean of any uniform probability distribution is
A. (b – a)/2
B. (a + b)/2
C. ÎŁ x/ Îˇ
20) For the normal distribution, the mean plus and minus 1.96standard deviations will include about what percent of theobservations?
21) For a standard normal distribution, what is the probabilitythat z is greater than 1.75?
22) A null hypothesis makes a claim about a
A) Population parameter
B. sample statistic
C. sample mean
D. Type II error
23) What is the level of significance?
24) Suppose we test the difference between two proportions at the0.05 level of significance. If the computed z is -1.07, what is ourdecision?
25) Which of the following conditions must be met to conduct a testfor the difference in two sample means?
26) Which of the following statements about the two sample sizes isNOT true? Assume the population standard deviations are equal.
27) What is the chart called when the paired data (the dependentand independent variables) are plotted?
A. Scatter diagram
B. Bar chart
C. Pie chart
28) What is the variable used to predict the value of anothercalled?
A. Independent variable
B. Dependent variable
C. Correlation variable
D. Variable of determination
29) Twenty randomly selected statistics students were given 15multiple-choice questions and 15 open-ended questions, all on thesame material. The professor was interested in determining on whichtype of questions the students scored higher. This experiment is anexample of
A. a one sample test of means
B. a two sample test of means
C. a paired t-test
D. a test of proportions
30) The measurements of weight of 100 units of a productmanufactured by two parallel processes have same mean but thestandard of process A is 15 while that of B is 7. What can youconclude?
A. The weight of units in process A are grouped closer than inprocess B
B. The weight of units in process B are grouped closer than inprocess A
C. Both processes are out of control
D. More data is needed to draw a conclusion