Statistics Questions & Answers

Statistics Questions & Answers A class interval, which is the width of a class, can be determined by subtracting the lower limit of a class from the lower limit of the next higher class. - ANSWER: A difference between calculating the sample mean and the population mean is - ANSWER: Only in the symbols, we use n instead of N. A disadvantage of the range is - ANSWER: Only two values are used in its calculation. A discrete variable is - ANSWER: Can assume only certain clearly separated values. A frequency distribution groups data into classes showing the number of observations in each class. - ANSWER: A negatively skewed distribution is not symmetrical. The long tail is to the left or in the negative direction. - ANSWER: A nominal scale variable is - ANSWER: Usually the result of counting something. A pie chart is used when we wish to emphasize - ANSWER: The percent of observations in each category. A population is a collection of all individuals, objects, or measurements of interest. - ANSWER: True A relative frequency distribution shows the number of observations in each class. - ANSWER: A row of a stem-and-leaf chart appears as follows: 3 | 0 1 3 5 7 9. Assume that the data is rounded to the nearest unit. - ANSWER: A sample is a portion or part of the population of interest. - ANSWER: True A set of ordinal, interval or ratio level data may only have one mode. - ANSWER: A study of the scores on an in-plant course in management principles and the years of service of the employees enrolled in the course resulted in these statistics: - Mean test score was 200 with a standard deviation of 40 - Mean number of years of service was 20 years with a standard deviation of 2 years. In comparing the relative dispersion of the two distributions, what are the coefficients of variation? - ANSWER: