Representing Data

EQ: How do you determine the best way to represent a set of

data?

Frequency Tables

• A frequency table shows how often something occurs

• A frequency table shows the category, tally, and frequency of items

• The best time to use a frequency table is to keep track and organize data

Frequency Tables

Trip Location

Tally Frequency

San Diego /// 3

Chicago //// //// / 11

Boston //// // 7

Denver //// 5

Bar Graphs

• A bar graph compares amounts• A bar graph is best used to compare

data• A multiple bar graph also includes a key

Bar Graphs

0

10

20

30

40

50

60

70

80

90

1st Qtr 2nd Qtr 3rd Qtr 4th Qtr

East West North

222324252627282930

6thGrade

7thGrade

8thGrade

Number of Students

Single Bar Graph Multiple Bar Graph

Pictograph

• Uses pictures to represent numbers• Has a key that tells the value of each

picture• The best time to use this graph is to

compare data• It is also very eye-catching and is often

used in newspapers and magazines

Pictograph

Histogram

• A histogram is a special bar graph that shows how ranges of data change or how they differ

• There are no spaces between the bars• A histogram is used to compare data

Histogram

Line Plots

• A line plot is a graph that shows frequency of data along a number line.

• In creating a line plot, you should include your entire range of numbers.

Line Plots

• It is best to use a line plot when you want to quickly analyze your data.

• Line plots allow you to easily identify your outliers- numbers that are significantly smaller or larger than the other values.

Line Plot

Number of Pets in Each Household

The numbers along the x axis represent the number of pets, the x’s represent the households with those number of pets

Line Plot

Line Graph

• A line graph shows how something has changed over time.

• By looking at the line graph you can determine if the data is increasing, decreasing, or staying the same over time.

• Line graphs help predict the outcome of an event.

Parts of a Line Graph

• Title of the graph, • The x and y axes, labels of axes, and the

equal intervals along the axes, • and the representation of the data as

points connected by a line.

Line Graph

Use the data in the table to create a line graph.

Circle Graph

• A circle graph shows the relationship between parts to a whole

• A circle graph is interpreted by comparing the “pieces of the pie” to one another

• Circle graphs are best used when comparing percentages

• The whole circle must total 100%

Circle Graphs

Hair Color of Students

black29%

brown36%

blonde21%

red14%

black

brown

blonde

red