In: Statistics and Probability
The table below gives beverage preferences for random samples of teens and adults.
Teens |
Adults |
Total |
|
Coffee |
50 |
200 |
250 |
Tea |
100 |
150 |
250 |
Soft Drink |
200 |
200 |
400 |
Other |
50 |
50 |
100 |
400 |
600 |
1,000 |
We are asked to test for independence between age (i.e., adult and
teen) and drink preferences. If the value of the test statistic is
greater than the critical value of the test statistic, what is the
result of the test?
Select one:
A. hypothesis of independence can be rejected
B. hypothesis of independence cannot be rejected
C. test is inconclusive
D. None of these alternatives is correct.
H0: There is independence between age (i.e., adult and teen) and drink preferences
H1: There is not independence between age (i.e., adult and teen) and drink preferences
Let the los be alpha = 5%
The expected frequencies are
Teens | Adults | Total | |
Coffee | 100 | 150 | 250 |
Tea | 100 | 150 | 250 |
Soft Drink | 160 | 240 | 400 |
Other | 40 | 60 | 100 |
Total | 400 | 600 | 1000 |
The chi-square contribution values are
Oi | Ei | (Oi-Ei)^2 /Ei |
50 | 100 | 25 |
200 | 150 | 16.6667 |
100 | 100 | 0 |
150 | 150 | 0 |
200 | 160 | 10 |
200 | 240 | 6.6667 |
50 | 40 | 2.5 |
50 | 60 | 1.6667 |
Total: | 62.5001 |
Degrees of freedom: 3
Test Statistic, X^2: 62.5000
Critical X^2: 7.814736
P-Value: 0.0000
Here Test statistic of Chisquare value > Chisquare critical value and P-value < alpha 0.05 so we reject H0
Thus we conclude that there is not independence between age (i.e., adult and teen) and drink preferences
Correct answer: Option (A). hypothesis of independence can be rejected