# Intro to Probability & Stats

 True or False? The sum of all class frequencies is equal to the size of the data set. True True or False? The cumulative frequency always increases from lower to higher classes True True or False? A class frequency cannot be equal to zero. False It may be equal to zero if none of the scores fallinto a certain class. However, if the upper class turns out empty, itmeans that the class width was chosen incorrectly: it's is too large. How do we define the class width while arranging a data set in classes? The data range (maximum minus minimum) is divided by the number of classes. The quotient can be rounded UP and never down. If the calculated class width is a decimal, how do we round it off? We round it only UP. If the class width turns out a whole number,increase it by 1; otherwise, the upper class will be wider than theother classes. True or False? The lower limit of the lowest class must be equal to the smallest number in the data set. False It may be even smaller, if that is convenient. True or False? The class midpoint is midway betweeen the lower and the upper limit of the same class. True True or False? For a given data set and given number of classes, there still may be a variety of class distributions. True You still can vary the class width and the lower limit of the lowest class. Authorju1iet ID3938 Card SetIntro to Probability & Stats DescriptionA basic interactive activity created by the instructor for memorizing key concepts learned in Chapter 2, week 2 Updated2010-01-10T06:18:25Z Show Answers