In: Statistics and Probability
Presidential candidate Donald Trump caused quite a stir over his recent announcement to meet with the North Korean President. A sample of 400 hundred people were asked where they get their news and if they agree with the decision to meet with the North Korean President.
Watches | Watches | Watches | Watches | |
Fox News | CNN | MSNBC | Disney Channel | |
Should meet NKO Pres | 60 | 50 | 60 | 55 |
Should not meet NKO Pres | 30 | 70 | 20 | 55 |
a. At the 5% level does the above data support the hypothesis that ones opinions about the meetings and their favorite news channel are unrelated? Write out the expected frequency table.
We are given the data
Observed | Watches | Total | |||
FOX | CNN | MSNBC | DISNEY | ||
Should | 60 | 50 | 60 | 55 | 225 |
Should not | 30 | 70 | 20 | 55 | 175 |
Total | 90 | 120 | 80 | 110 | 400 |
Null Hypothesis: Ones opinions about the meetings and their favorite news channel are unrelated
Alternate Hypothesis: Ones opinions about the meetings and their favorite news channel are related
Test Statistic:
Where are the Observed and expected values of the ijth Cell. , are the ith Row and jth column totals with T being the overall Total.
We shall now calculate the expected frequency table:
Expected | Watches | Total | |||
FOX | CNN | MSNBC | DISNEY | ||
Should | 50.625 | 67.5 | 45 | 61.875 | 225 |
Should not | 39.375 | 52.5 | 35 | 48.125 | 175 |
Total | 90 | 120 | 80 | 110 | 400 |
O-E | Watches | |||
FOX | CNN | MSNBC | DISNEY | |
Should | 9.375 | -17.5 | 15 | -6.875 |
Should not | -9.375 | 17.5 | -15 | 6.875 |
The Chi square critical value at 3 df=7.815 at 5% level of significance.
Since the calculated value 27.5131>tabulated value, we reject the Null hypothesis and conclude that at the 5% level the above data support that ones opinions about the meetings and their favorite news channel are related.
The expected frequency table:
Expected | Watches | Total | |||
FOX | CNN | MSNBC | DISNEY | ||
Should | 50.625 | 67.5 | 45 | 61.875 | 225 |
Should not | 39.375 | 52.5 | 35 | 48.125 | 175 |
Total | 90 | 120 | 80 | 110 | 400 |