Chapter 2, Problem 1CR

Critical Thinking Consider these types of graphs: histogram, bar graph. Pareto chart, pie chart, stem-and-leaf display.

(a) Which are suitable for qualitative data?

(b) Which are suitable for quantitative data?

To determine

Whether the graph types histogram, bar graph, Pareto chart, Pie chart, and stem-and-leaf are suitable for qualitative data.

Answer to Problem 1CR

Solution: The graph types bar graph, Pareto chart, and Pie chart are suitable for qualitative data.

Explanation of Solution

Qualitative data involves categories that are not numerical, such as eye color, type of coffee bean, and species of birds seen in a garden. The only numbers that can be related to these categories are frequencies, so only charts with one numerical axis can be used. It can be represented through pictures that explore the data in a visual way and visual representations focus on the themes found in the data.

Bar graph and Pareto chart are a way to visually represent qualitative data. Data are displayed either horizontally or vertically and allow viewers to compare items, such as amounts, characteristics, times, and frequency.

Pie chart graph is helpful when graphing qualitative data, where the information describes a trait or attribute and is not numerical. Each slice of pie represents a different category, and each trait corresponds to a different slice of the pie.

The graph types bar graph, Pareto chart, and Pie chart are suitable for qualitative data.

To determine

Whether the graph types histogram, bar graph, Pareto chart, Pie chart, and stem-and-leaf are suitable for quantitative data.

Answer to Problem 1CR

Solution: All graph types histogram, bar graph, Pareto chart, Pie chart, and stem-and-leaf are suitable for quantitative data.

Explanation of Solution

Quantitative data is information about quantities, that is, information that can be measured and written down with numbers. 

A histogram is kind of graph that uses bars in its display. This type of graph is used with quantitative data. 

A Bar graph is a diagram in which the numerical values of variables are represented by the height or length of lines or rectangles of equal width. In Pareto graph, data are displayed either horizontally or vertically and allow viewers to compare items, such as amounts, characteristics, times, and frequency.

A stem and leaf plot breaks each value of a quantitative data set into two pieces: a stem, typically for the highest place value, and a leaf for the other place values. It provides a way to list all data values in a compact form.

A pie chart is a circular chart used to compare parts of the whole. It is divided into sectors that are equal in size to the quantity represented.

All graph types are suitable for quantitative data.