Displaying Data

Displaying data is an important part of understanding and interpreting information. There are several ways to display data, including tables, charts, and graphs. Each method has its own advantages and is suited for different types of data.

Types of Data Displays

1. Tables: Tables are a clear and organized way to display data, especially when dealing with large amounts of information. They are useful for displaying numerical data and making comparisons between different categories.

2. Charts: Charts, such as bar charts, line charts, and pie charts, are visual representations of data. They are useful for showing trends, comparisons, and proportions within the data.

3. Graphs: Graphs, including line graphs, scatter plots, and histograms, are used to visually represent the relationship between variables. They are helpful for displaying patterns and relationships within the data.

Choosing the Right Display

When choosing a method to display data, it's important to consider the type of data and the purpose of the display. For example, if you want to compare the sales performance of different products over time, a line chart would be a good choice. If you want to show the distribution of ages in a population, a histogram would be more appropriate.

Study Guide

Key Concepts

Understanding the different types of data displays
Knowing when to use tables, charts, and graphs
Interpreting the information presented in each type of display
Choosing the right display for a given set of data

Practice Questions

What are the advantages of using a table to display data?
When would you use a bar chart instead of a line chart?
How can a histogram help in understanding the distribution of a data set?
Give an example of a real-world situation where a scatter plot would be useful.

Practice Problems

1. Create a bar chart to display the sales figures for the following products:

Product	Sales
A	150
B	200
C	100

2. Use a line graph to show the temperature variations over a week with the following data:

Day	Temperature (°C)
Monday	25
Tuesday	28
Wednesday	26
Thursday	24
Friday	30
Saturday	29
Sunday	27

3. Create a histogram to display the distribution of the following data set:

Age Group	Number of People
10-20	15
21-30	25
31-40	20
41-50	18
51-60	12

These practice problems will help reinforce your understanding of the different data display methods and how to use them effectively.

◂Math Worksheets and Study Guides Eighth Grade. Displaying data

Organizing & Displaying Data

The resources above cover the following skills:

Data Analysis and Probability (NCTM)

Formulate questions that can be addressed with data and collect, organize, and display relevant data to answer them.

Select, create, and use appropriate graphical representations of data, including histograms, box plots, and scatterplots.

Select and use appropriate statistical methods to analyze data.

Discuss and understand the correspondence between data sets and their graphical representations, especially histograms, stem-and-leaf plots, box plots, and scatterplots.

Develop and evaluate inferences and predictions that are based on data.

Make conjectures about possible relationships between two characteristics of a sample on the basis of scatterplots of the data and approximate lines of fit.

Grade 8 Curriculum Focal Points (NCTM)

Data Analysis and Number and Operations and Algebra: Analyzing and summarizing data sets

Students use descriptive statistics, including mean, median, and range, to summarize and compare data sets, and they organize and display data to pose and answer questions. They compare the information provided by the mean and the median and investigate the different effects that changes in data values have on these measures of center. They understand that a measure of center alone does not thoroughly describe a data set because very different data sets can share the same measure of center. Students select the mean or the median as the appropriate measure of center for a given purpose.

Connections to the Grade 8 Focal Points (NCTM)

Data Analysis: Building on their work in previous grades to organize and display data to pose and answer questions, students now see numerical data as an aggregate, which they can often summarize with one or several numbers. In addition to the median, students determine the 25th and 75th percentiles (1st and 3rd quartiles) to obtain information about the spread of data. They may use box-and-whisker plots to convey this information. Students make scatterplots to display bivariate data, and they informally estimate lines of best fit to make and test conjectures.