Intro to Statistics MCCC Ch. 2 Exam Questions and Answers

Intro to Statistics MCCC Ch. 2 Exam Questions and Answers After constructing a relative frequency distribution summarizing IQ scores of college students, what should be the sum of the relative frequencies? - Answer-If percentages are used, the sum should be 100%. If proportions are used, the sum should be 1. Among fatal plane crashes that occurred during the past 70 years, 269 were due to pilot error, 54 were due to other human error, 665 were due to weather, 85 were due to mechanical problems, and 479 were due to sabotage. Construct the relative frequency distribution. What is the most serious threat to aviation safety, and can anything be done about it? What is the relative frequency for pilot error, other human error, weather, mechanical problems, and sabotage? Round to one decimal point. What is the most serious threat to aviation safety, and can anything be done about it? - Answer-Pilot Error: 17.3% Other Human Error: 3.5% Weather: 42.8% Mechanical problems: 5.5% Sabotage: 30.9% Weather is the most serious threat to aviation safety. Weather monitoring systems could be improved. Whi Which characteristic of data is a measure of the amount that the data values vary? a. variation b. distribution c. time d. center - Answer-variation - are sample values that lie very far away from the majority of the other sample values. - Answer-outliers A -- helps us understand the nature of the distribution of a data set. - Answer-frequency distribution Class width is found by -------. - Answer-subtracting a lower class limit from the next consecutive lower class limit In a -- distribution, the frequency of a class is replaced with a proportion or percent. - Answer-relative frequency The population of ages at inauguration of all U.S. Presidents who had professions in the military is 62, 46, 68, 64, 57. Why does it not make sense to construct a histogram for this data set? - Answer-With a data set that is so small, the true nature of the distribution cannot be seen with a histogram.