Types of graphs

MST 101

Dr. Maureen Markel September, 2006

Column or bar : for discontinuous, unordered or qualitative (male, female) data.

0

5

10

15

20

25

30

Num

ber o

f Stu

dent

s

TV dancing sports studying

Favorite Activity of MST Students

Pie: contribution of each category to the total (e.g. proportion of a population of mice that are white, gray, or black).

Favorite Activities of MST students

TV29%

dancing16%

sports21%

studying34%

Clustered Bar: for situations when you wish to express the part of the whole that data play (e.g. percent of the diet that four foods occupy for three species of fish).

Favorite Activities of MST students

05

101520253035

TV dancing sports studying

num

ber o

f stu

dent

s

Males

Females

XY Scatter Plot: For continuous data. The data are pairs of X and Y values (although there can be additional Y’s) representing an independent and one or more dependent variables.

Relationship of Calories to Fat in McDonalds' Burgers

0

10

20

30

40

0 100 200 300 400 500 600

Calories

Fat (

g)

The data will appear as points that can be connected by lines.

In this kind of graph, the points can be connected by lines or a trend line can be added to indicate the fit of a line to the data.

Line Graph: Similar in use to X-Y for continuous quantitative independent variables. Intervals on X-axis must be uniform and data must be ordered.

Price of Eggs over the Decade

0.85

0.9

0.95

1

1.05

1989 1990 1991 1992 1993 1994 1995 1996

Year

Pric

e ($

)

Line graphs usually show trends over time.

Creating a Pie Graph from a bar/column graph

1. Compute Total2. Find percentage of each part3. Multiply each percentage by total degrees in circle4. Create circle and draw radius5. Measure angle using the last line drawn

0

5

10

15

20

25

30

Num

ber o

f Stu

dent

s

TV dancing sports studying

Favorite Activity of MST Students

Questions