1. 9.4 Displays of Data Essential Question:
How can you display data to help you make decisions?

2. Shows data in specific categories
bar graph:
Shows data in specific categories
Ex:
Number of students taking each college class

3. double bar graph: Compares data from within categories
Use different colors to show urban and rural speed limits. 80 60 40 20
State Urban Rural
Florida mi/h 70 mi/h
Texas mi/h 70 mi/h
Vermont 55 mi/h 65 mi/h

4. Shows frequency of data values in intervals of the same size
Histogram:
Shows frequency of data values in intervals of the same size
Special type of bar graph
no space between the bars
Ex:
Number of hours of tv watched by students 20 16 12 8 4
1–3
4–6
7–9
1–3
Frequency
Number of Hours of TV 15
4–6 17
7–9

5. circle graph (or pie chart):
Shows how data is divided into parts of a whole - PERCENTS!!
Ex:
Favorite subjects of a group of students.

6. Shows how data changes over time
line graph:
Shows how data changes over time
Ex: Visitors to National Parks each month
432
May
657
June
856
July
723
August
Visitors
Months

7. Orders numerical data shows how they are distributed
stem-and-leaf plot:
Orders numerical data shows how they are distributed
(least to greatest)
The data shows the number of years coached by the top 15 coaches in the all-time NFL coaching victories. Make a stem-and-leaf plot of the data. Then find the number of coaches who coached fewer than 25 years.
33, 40, 29, 33, 23, 22, 20, 21, 18, 23, 17, 15, 15, 12, 17
List the leaves for each stem from least to greatest.
Stems Leaves 2 5 5 7 7 8 1 2 3 4 1 2 3 3 9 3 3

8. Shows the number of times each value occurs in a data set
dot plot:
Shows the number of times each value occurs in a data set
Ex: number of times she babysat each # of hours in July. 6 3 4 8
Wk 4 2 1 5
Wk 3 7
Wk 2
Wk 1 Su S F Th W T M
X X X X X X
X X X X
X X X X
X X X
X X X
X X X
X X
X X X

9. scatter plot:
Shows the relationships between two data sets by using ordered pairs in a coordinate plane (Correlations)
Ex:
Shows the relationship between age and speed of walking

10. Pictograph (or Infographics):
Shows data using pictures or a theme

11. box-and-whisker plot:
Shows the variability of a data set by using quartiles
Basketball Players
Baseball Players
t Heights of Basketball and Baseball Players (in.)
Each section has ¼ of data (¼ of data, ¼ of data, ¼ of data, ¼ of data)
Upper & Lower extremes: points at end of whiskers
Interquartile Range: Includes upper quartile and lower quartile together (the entire box)
(inter=inside) (Quartile= 4 parts) (range=between 2 #’s)
lower half of the box is the lower quartile, upper half of the box is the upper quartile

12. Venn Diagram:
show relationships between two or more data sets.

13. Which Data Display Do We Use?

16. Your Turn
What type of display would be most appropriate.
1. The number of points scored per game by the basketball team during the season.
2. The number of books read by each student in third period English class.
line graph
line plot

17. Your Turn
3. The percentage of the variety of cakes made by a bakery.
4. The number of magazine subscriptions sold by each member of the sales staff.
circle graph
bar graph

18. Your Turn
5. Identify the type of display that would be most appropriate for the description of the given data set.
The number of points scored per match by a rugby team during the season.
A. line graph
B. line plot
C. bar graph
D. circle graph

19. Your Turn
6. Identify the type of display that would be most appropriate for the description of the given data set.
The shoe size of a group of students.
A. line graph
B. line plot
C. bar graph
D. circle graph

20. the population of the U.S. divided into age groups
Your Turn
7. Identify the type of display that would be most appropriate for the description of the given data set:
the population of the U.S. divided into age groups
Histogram: show frequencies of ages in intervals of the same size

21. Your Turn
8. Number of girl and guy students in your school who play basketball, soccer, and football.
Double Bar Graph: show categories

22. Your Turn
9. Identify the type of display that would be most appropriate for the description of the given data set.
The percent of salary spent by a person on different items.
A. line graph
B. line plot
C. bar graph
D. circle graph

23. Your Turn
10. Identify the type of display that would be most appropriate for the description of the given data set.
The grades earned by a student in different subjects.
A. line graph
B. line plot
C. bar graph
D. circle graph

24. 11. Correlation between test scores and number of hours
Your Turn
11. Correlation between test scores and number of hours
Scatterplot: shows relationship between two pieces of information