Chapter 2: Describing Data

Suppose you are trying to summarize a data set with a maximum value of 70 and a minimum value of 1. If you have decided to use 7 classes, which one of the following would be a reasonable class interval? 1 10 7 70

10

Place the following steps used in construction a frequency distribution into the correct order. Decide on number of classes Set individual class limits Tally the number of observations in each class Determine class width

Decide on number of classes Determine class width Set individual class limits Tally the number of observations in each class

Which of the following is NOT a useful practice in setting individual class limits for a frequency distribution? Excluding outliers that case the interval to be too wide. Set clear limits so that observations will only fit one limit. Place excessive interval space equally in the two tails of the distribution. Round the class interval up to get a convenient class size.

Excluding outliers that case the interval to be too wide.

A frequency distribution table shows the number of observations for each class interval of data.How is this data plotted as a frequency polygon?

Frequency is plotted on the vertical axis and the class midpoint is plotted on the horizontal axis.

Which of the following are used to summarize quantitative data? Select all that apply. Frequency table Frequency polygon Bar Chart Histogram

Frequency polygon Histogram

Which of the following are true regarding the class midpoint? Select all that apply. Its is halfway between the lower limits of two consecutive classes. Its is halfway between the upper limits of two consecutive classes. It best represents the values in a class. It is halfway between the highest and lowest classes. The average value of the observations in a class interval.

Its is halfway between the lower limits of two consecutive classes. Its is halfway between the upper limits of two consecutive classes. It best represents the values in a class.

Which of the following can be observed from a histogram? Select all that apply. The approximate number of observations. The spread of the data. The concentration of the data. The Shape of the distribution. The relationship between two variables.

The approximate number of observations. The spread of the data. The concentration of the data. The Shape of the distribution.

Which of the following is a feature of relative frequency distribution?

The sum of the relative frequencies must be one (Assuming no rounding errors)

Relative Frequencies are:

the fraction or percentage of observations in each class interval.

Which of the following would be a use for a frequency table? Select all that apply. Gender of students in a Business Statistics course. Age of students in a Business Statistics course. State of residence of students in a Business Statistics course. Majors of students in a Business Statistics course.

Gender of students in a Business Statistics course. State of residence of students in a Business Statistics course. Majors of students in a Business Statistics course.