Chapter 1, Section 3: Chapter 1, Section 3: Communicating with Communicating with

GraphsGraphs

(C.P. Exploring Science)(C.P. Exploring Science)

GRAPHSGRAPHS

A visual display of information or A visual display of information or datadata

Why use graphs? Why use graphs? They show patterns in data better than They show patterns in data better than

a tablea table

GRAPHSGRAPHS

Graphs make understanding the data Graphs make understanding the data easier easier

With graphs, you can see patterns and With graphs, you can see patterns and trends and make conclusions trends and make conclusions

Which Which display is display is easier to easier to understandunderstand??

Race/Ethnicity AP Examinee Population

Asian, Asian American or Pacific Islander 10.2%Black or African American 8.2%Hispanic or Latino 15.5%American Indian or Alaska Native 0.6%White 59.4%Not reported/other 6.1%

GRAPHSGRAPHS

What are the three common types of What are the three common types of graphs?graphs? LINE, BAR, CIRCLELINE, BAR, CIRCLE

LINE GRAPHSLINE GRAPHS

Show the relationship of how the dependent variable Show the relationship of how the dependent variable changes due to changes in the independent variable changes due to changes in the independent variable

LINE GRAPHSLINE GRAPHS

You can show You can show more than one more than one event on the same event on the same graph as long as graph as long as the relationship is the relationship is the samethe same

NEEDS A KEY!NEEDS A KEY!

CONSTRUCTING LINE GRAPHSCONSTRUCTING LINE GRAPHS x-axis is the Independent Variable x-axis is the Independent Variable y-axis is the Dependent Variabley-axis is the Dependent Variable

CONSTRUCTING LINE GRAPHSCONSTRUCTING LINE GRAPHS

Because the points are RELATED, connect them Because the points are RELATED, connect them This is how you can tell if a line graph is most This is how you can tell if a line graph is most

appropriate. appropriate. If you are not looking to see CHANGE If you are not looking to see CHANGE then you don’t need a line graphthen you don’t need a line graph..

Should this be a line graph?

NO! There is no relationship in the change. It should be a bar graph.

CONSTRUCTING LINE GRAPHSCONSTRUCTING LINE GRAPHS

MEASUREMENT MEASUREMENT – all should be – all should be in the SAME in the SAME unit and be unit and be sure your sure your divisions make divisions make sense. sense.

Use a “break” Use a “break” if you need it.if you need it.

BAR GRAPHSBAR GRAPHS Used to compare TOTALS that don’t need to Used to compare TOTALS that don’t need to

show change over timeshow change over time Show comparisons of quantities counted at a Show comparisons of quantities counted at a

particular time.particular time.

BAR GRAPHSBAR GRAPHS Multiple bar graphs show two or more Multiple bar graphs show two or more

sets of data:sets of data:

Like a multiple line graph, you will need a key.

CIRCLE (PIE) GRAPHSCIRCLE (PIE) GRAPHS

Show how some fixed quantity is broken down Show how some fixed quantity is broken down into partsinto parts

The whole circle represents the totalThe whole circle represents the total The slices represent the PERCENTAGES of the The slices represent the PERCENTAGES of the

totaltotal

CIRCLE (PIE) GRAPHSCIRCLE (PIE) GRAPHS To create a circle graph, To create a circle graph,

start with the total and start with the total and divide each part by the divide each part by the total and multiply by 360⁰ total and multiply by 360⁰ to find the angle the slice to find the angle the slice will occupywill occupy FOR EXAMPLE: if the FOR EXAMPLE: if the

total number of grades total number of grades counted were 100 and counted were 100 and the number of A’s were the number of A’s were 31, to get the size angle 31, to get the size angle A’s occupy would be: A’s occupy would be:

31 ÷ 100 × 360⁰ = 112⁰31 ÷ 100 × 360⁰ = 112⁰ (size of the slice for A’s)(size of the slice for A’s)

WHAT’S WRONG WITH THESE WHAT’S WRONG WITH THESE GRAPHS???GRAPHS???

WHAT’S WRONG WITH THESE WHAT’S WRONG WITH THESE GRAPHS???GRAPHS???

WHAT’S WRONG WITH THESE WHAT’S WRONG WITH THESE GRAPHS???GRAPHS???

WHAT’S WRONG WITH THESE WHAT’S WRONG WITH THESE GRAPHS???GRAPHS???