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Explaining confidence. Here is an explanation from the Associated Press concerning one of its opinion polls. Explain briefly but clearly in what way this explanation is incorrect. For a poll of 1,600 adults, the variation due to sampling error is no more than three percentage points either way. The error margin is said to be valid at the 95 percent confidence level. This means that, if the same questions were repeated in 20 polls, the results of at least 19 surveys would be within three percentage points of the results of this survey.

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Answer:

The mistake in the analysis is saying that 95% of other polls' outcomes would be similar to the outcome of this poll. The correct statement would be that the outcomes of other surveys will be close to the actual result and not the outcome of this particular survey. Therefore, it is not right to say 95% means exactly 19 out of 20.

Step-by-step explanation:

The mistake in the analysis is saying that 95% of other polls' outcomes would be similar to the outcome of this poll. The correct statement would be that the outcomes of other surveys will be close to the actual result and not the outcome of this particular survey. Therefore, it is not right to say 95% means exactly 19 out of 20.

User Seub
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Answer:

The explanation in the question is wrong and the way it is incorrect is explained as follows

It is wrong to say that the next 200 polls will behave in the same manner and have the same result as in the poll case considered. On carrying out more experiments, what should be seen is that the 95% results comes from the infinite number of experiments held and not on the basis of a single considered experiment. Furthermore, it is improper to say that 19 out of 20 surveys would lie between 3 percentage points.Knowing that a single experiment has results of 95% confidence intervals does not mean that it would happen for all similar cases

Step-by-step explanation:

User Tbert
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