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A proportion estimate is within 0.05 of the actual value of the population proportion. Given that the sampling distribution of p is approximately normal, explain how this information relates to the margin of error in confidence interval estimation.

User Crysta
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Final answer:

The margin of error in confidence intervals represents the range of values around the sample estimate where the true population proportion is expected to fall. It's 0.05 in this case, indicating that the confidence interval is constructed as (p' - 0.05, p' + 0.05), assuming a normal sampling distribution. This margin of error factors into determining the level of confidence and sample size requirements.

Step-by-step explanation:

When a proportion estimate is within 0.05 of the actual value of the population proportion, and the sampling distribution of p is approximately normal, this relates to the concept known as the margin of error in confidence interval estimation. The margin of error is the range of values above and below the sample statistic in a confidence interval; in this case, it is 0.05. This means that the confidence interval would be constructed as (p' - 0.05, p' + 0.05), where p' is the sample proportion. If multiple samples were taken and confidence intervals calculated, we would expect that the interval would contain the true population proportion in a certain percentage of the cases, corresponding to the chosen confidence level. For instance, if we have 95% confidence level, we'd say we are 95% confident that the interval captures the true population proportion.

The margin of error reflects the degree of uncertainty associated with the sample estimate. It is dependent on the standard deviation of the sampling distribution and the desired confidence level, denoted by z-scores in the formula for the margin of error (EBP). For example, for a 95% confidence level, the z-score is approximately 1.96. This means that if the null hypothesis is true, there is a 2.5% chance that the sample proportion falls outside the calculated confidence interval on either end of the distribution. The size of the margin of error can also determine the necessary sample size to achieve a certain level of accuracy, as seen in scenarios where specific confidence intervals are desired for a known population proportion.

User Nimmi
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