A researcher used a procedure to select a sample of n objects from a population in such a way that each member of the population is chosen strictly by chance, is equally likely to be chosen, and every possible sample of size n has the same chance of
selection. The procedure used by the researcher is known as:A) descriptive statistics.
B) inferential statistics.
C) simple random sampling.
D) None of the above
Q. 2When grouping data into classes it is recommended to have:
A) exactly 5 classes.
B) between 5 and 20 classes.
C) at least 5 classes.
D) at most 10 classes.
Q. 3Consider the following frequency distribution generated by Excel. What is the missing frequency value identified by the asterisk?Bin Frequency Cumulative 584 1 4.001774.4 64.002964.8 4 80.004155.2 3 92.005345.6 1 96.00More 1 100.00
A) 3
B) 15
C) 16
D) 25
Q. 4Consider the following frequency distributions generated by Excel. What is the missing cumulative value identified by the asterisk?Bin Frequency Cumulative 12.8 1 5.0041.6 5 30.0070.4 6 60.0099.2 6 More 2 100.00
A) 60.00
B) 5.00
C) 100
D) 90
Q. 5The length of time it takes to assemble a particular electronic component varies from one employee to another. Management has collected the time (in minutes) it took 20 different employees to assemble the component.
The information is summarized in the following frequency distribution generated by Excel:Bin Frequency Cumulative 10 1 5.0015 9 50.0020 1 55.0025 7 90.00More 2 100.00Which of the following statements is true?A) 50 of all the workers took exactly 15 minutes to assemble the component.
B) 100 of all the workers took longer than 25 minutes to assemble the component.
C) Eleven workers assembled the component in 20 minutes or less.
D) Seven workers took 25 minutes or longer to assemble the component.
Q. 6The width of each bar in a histogram corresponds to the:
A) midpoint of the class.
B) number of observations in the class.
C) boundaries of the class.
D) percentage of observations in the class.
Q. 7Which of the following statements involve descriptive statistics as opposed to inferential statistics?
A) The Alcohol, Tobacco and Firearms Department reported that Seattle had 1,825 registered gun dealers in 2013.
B) Based on a survey of 380 magazine readers, the magazine reports that 30 of its readers prefer double column articles.
C) The FAA samples 425 traffic controllers in order to estimate the percent retiring due to job stress related illness.
D) Based on a sample of 350 professional baseball players, a baseball magazine reported that 23 of the parents of all professional baseball players did not play baseball.