Question

1. Provide circumstances and examples where a pie chart cannot be drawn, but a bar graph could be drawn? Same for where a pie chart cannot be drawn, but a bar graph could be drawn.

2. For each variable, identify the type of variable, discuss the type of graphical summary you might be able to draw to provide a visual summary of the data. The data: you learned the following information about 50 individuals: age, income, marital status, number of vehicles in household.

Answer 1

1.Pie chart can only show proportions Where as bar graphs can display changes in quantities over time.

For example,

a.If you were showing the results for a class president election in school, each candidate would have his or her own bar on the x-axis and the values on the y-axis would be number of votes the candidate received.

b)If you were showing the revenues of various companies, you could use a bar chart with a bar for each company and the length corresponding to its revenue in dollars.

In both of the abive cases, you can easily see at a glance the category (in the examples, the candidate or company) that has the highest value (in votes or dollars, in the example), and the graph conveys the main information.

In these cases pie chart will not be of much use.

Pie chart works well for displaying a breakdown of sales for each item for a business. Your total sales are the whole “pie,” but the slices tell you how much each product contributes. You might sell fruit, for example, and a pie chart of the different types of fruit you sell shows that apples make up the largest chunk of your sales, followed by bananas.

This information will be more effective by Pie chart only not by Bar chart.

2. Age, income, , number of vehicles in household all are quantitative variables. But Marital status is a qualitative variable. .For Age, income no. Of vehicles in household. Histogram will be effective by making class inteval of equal width.For graphical representation of Maritial status Pie chart will be more effective.