F Distribution and ANOVA: Practice
1.6
2008/06/22 15:17:54 GMT-5
2008/08/15 13:42:19.608 GMT-5
Barbara
Illowsky
illowskybarbara@deanza.edu
Susan
Dean
deansusan@deanza.edu
Connexions
cnx@cnx.org
elementary
statistics
This module provides a practice on F Distribution and ANOVA as a part of Collaborative Statistics collection (col10522) by Barbara Illowsky and Susan Dean.
Student Learning Outcome
- The student will explore the properties of ANOVA.
Given
Suppose a group is interested in determining whether teenagers obtain their drivers licenses at approximately the same average age across the country.
Suppose that the following data are randomly collected from five teenagers in each region of the country. The numbers represent the age at which teenagers obtained their drivers licenses.
Northeast
South
West
Central
East
16.3
16.9
16.4
16.2
17.1
16.1
16.5
16.5
16.6
17.2
16.4
16.4
16.6
16.5
16.6
16.5
16.2
16.1
16.4
16.8
x
¯
=
size 12{ {overline {x}} ={}} {}
________
________
________
________
________
s
2
=
size 12{s rSup { size 8{2} } ={}} {}
________
________
________
________
________
Hypothesis
State the hypotheses.
Ho size 12{H rSub { size 8{O} } } {}:Ha size 12{H rSub { size 8{a} } } {}:
Data Entry
Enter the data into your calculator or computer.
degrees of freedom - numerator:
df(n)= size 12{ ital "df" \( n \) ={}} {}
d
f
(
1
)
=
4
degrees of freedom - denominator:
df(d)= size 12{ ital "df" \( d \) ={}} {}
d
f
(
2
)
=
15
F test statistic =
Test statistic
=
F
=
4.22
p-value =
0.017
Decisions and Conclusions
State the decisions and conclusions (in complete sentences) for the following preconceived levels of
α size 12{α} {} .
α=0.05 size 12{α=0 "." "05"} {}
Decision:
Conclusion:
α
=
0
.
01
size 12{α=0 "." "01"} {}
Decision:
Conclusion: