Television networks frequently run public opinion polls on issues of concern. One network conducted a scientific poll asking a q
uestion concerning the approval rating of the way President Obama was handling the Iraq War. At about the same time a second network ran an online poll using a very similar question. The results of the two polls are summarized in the following table. Poll
Scientific Online
Approve 339 385
Disapprove 780 573
Total 1119 958
We would like to test to see if the two polls are consistent with respect to the proportion who approve of President Obama's handling of the war
If the x^2 test is used to test the null hypothesis, the expected cell count in the online poll for those who approve and that cell's contribution to the value of the test statistic are, respectively,
Group of answer choices
a. 390.1 and 7.70.
b. 333.9 and 6.78.
c. 390.1 and 6.69.
d. 333.9 and 7.81.
e. 362.0 and 1.46.
Given that television networks frequently run public opinion polls on issues of concern. One network conducted a scientific poll asking a question concerning the approval rating of the way President Obama was handling the Iraq War. At about the same time a second network ran an online poll using a very similar question.
Observed data is
Poll Scien Online total
approve 339 385 724
disapprove 780 573 1363
1119 958 2087
(Two tailed chi square test)
Let us find out expected and chi square
Expected = row total x column total/grand total
The cell count expected in the online poll for those who approve
The probability that a coin flip is a head or a tail is 0.5. The probability that a coin flip is either a head or a tail is 1. The probability that a three-coin-flip is two heads and a head or a tail is 0.25.