In: Math
A magazine subscriber study asked, "In the past 12 months, when traveling for business, what type of airline ticket did you purchase most often?" A second question asked if the type of airline ticket purchased most often was for domestic or international travel. Sample data obtained are shown in the following table.
Type of Ticket | Type of Flight | |
---|---|---|
Domestic | International | |
First class | 29 | 22 |
Business class | 97 | 123 |
Economy class | 516 | 133 |
(a)
Using a 0.05 level of significance, is the type of ticket purchased independent of the type of flight?
State the null and alternative hypotheses.
H0: The type of ticket purchased is not
independent of the type of flight.
Ha: The type of ticket purchased is independent
of the type of flight.
H0: The type of ticket purchased is
independent of the type of flight.
Ha: The type of ticket purchased is not
independent of the type of
flight.
H0: The type of ticket purchased is not
mutually exclusive from the type of flight.
Ha: The type of ticket purchased is mutually
exclusive from the type of flight.
H0: The type of ticket purchased is mutually
exclusive from the type of flight.
Ha: The type of ticket purchased is not
mutually exclusive from the type of flight.
Find the value of the test statistic. (Round your answer to three decimal places.)
Find the p-value. (Round your answer to four decimal places.)
p-value =
State your conclusion.
Reject H0. We conclude that the the type of ticket purchased is not independent of the type of flight.
Do not reject H0. We cannot conclude that the type of ticket purchased and the type of flight are not independent.
Do not reject H0. We cannot conclude that the type of ticket purchased and the type of flight are independent.
Reject H0. We conclude that the type of ticket purchased is independent of the type of flight.
(b)
Discuss any dependence that exists between the type of ticket and type of flight.
A higher percentage of first class and business class tickets are purchased for domestic flights compared to international flights. Economy class tickets are purchased more for international flights.
The type of ticket purchased is independent of the type of flight.
A higher percentage of first class and business class tickets are purchased for international flights compared to domestic flights. Economy class tickets are purchased more for domestic flights.
A lower percentage of economy class tickets are purchased for domestic flights compared to international flights. First class and business class tickets are purchased more for domestic flights.
Given table data is as below
MATRIX | col1 | col2 | TOTALS |
row 1 | 29 | 22 | 51 |
row 2 | 97 | 123 | 220 |
row 3 | 516 | 133 | 649 |
TOTALS | 642 | 278 | N = 920 |
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calculation formula for E table matrix
E-TABLE | col1 | col2 |
row 1 | row1*col1/N | row1*col2/N |
row 2 | row2*col1/N | row2*col2/N |
row 3 | row3*col1/N | row3*col2/N |
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expected frequecies calculated by applying E - table matrix
formulae
E-TABLE | col1 | col2 |
row 1 | 35.589 | 15.411 |
row 2 | 153.522 | 66.478 |
row 3 | 452.889 | 196.111 |
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calculate chisquare test statistic using given observed
frequencies, calculated expected frequencies from above\
Oi | Ei | Oi-Ei | (Oi-Ei)^2 | (Oi-Ei)^2/Ei |
29 | 35.589 | -6.589 | 43.415 | 1.22 |
22 | 15.411 | 6.589 | 43.415 | 2.817 |
97 | 153.522 | -56.522 | 3194.736 | 20.81 |
123 | 66.478 | 56.522 | 3194.736 | 48.057 |
516 | 452.889 | 63.111 | 3982.998 | 8.795 |
133 | 196.111 | -63.111 | 3982.998 | 20.31 |
chisqr^2 o = 102.009 |
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set up null vs alternative as
null, ho: the type of ticket purchased is independent of the type
of flight.
alternative, h1: the type of ticket purchased is not independent of
the type of flight.
level of significance, alpha = 0.05
from standard normal table, chi square value at right tailed,
chisqr^2 alpha/2 =5.991
since our test is right tailed,reject Ho when chisqr^2 o >
5.991
we use test statistic chisqr^2 o = Σ(Oi-Ei)^2/Ei
from the table , chisqr^2 o = 102.009
critical value
the value of |chisqr^2 alpha| at los 0.05 with d.f (r-1)(c-1)= ( 3
-1 ) * ( 2 - 1 ) = 2 * 1 = 2 is 5.991
we got | chisqr^2| =102.009 & | chisqr^2 alpha | =5.991
make decision
hence value of | chisqr^2 o | > | chisqr^2 alpha| and here we
reject Ho
chisqr^2 p_value =0
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a.
H0: The type of ticket purchased is independent of the type of
flight.
Ha: The type of ticket purchased is not independent of the type of
flight.
b.
test statistic: 102.009
c.
p-value:0
d.
decision: Reject H0. We conclude that the the type of ticket
purchased
is not independent of the type of flight.
e. a higher percentage of first class and business class tickets
are purchased for international flights compared to domestic
flights