Question 56

Increasing the Sample Size Enhances Confidence Levels

To increase the level of confidence in a confidence interval, the researcher should increase the sample size. A larger sample size reduces the margin of error, leading to a more precise estimate of the population parameter.

A) Use a different estimator

Using a different estimator may not necessarily increase the confidence level of the interval. While different estimators can have varying properties, simply changing the estimator does not inherently affect the width of the confidence interval or the level of confidence unless it is more efficient than the current one.

B) Collect another sample

Collecting another sample could provide additional data, but it is not a direct method to increase the level of confidence. This action could be beneficial for validation or to increase the overall sample size, but on its own, it does not guarantee a higher confidence level unless the sample size is appropriately increased.

C) Decrease the sample size

Decreasing the sample size would have the opposite effect and is counterproductive. A smaller sample size typically leads to a wider confidence interval and a lower level of confidence, as it increases the margin of error and reduces the reliability of the estimate.

D) Increase the sample size

Increasing the sample size directly contributes to a higher level of confidence in the results. A larger sample reduces variability and provides a more accurate representation of the population, thus narrowing the confidence interval and enhancing the reliability of the estimate.

Conclusion

Increasing the sample size is the definitive method to improve the level of confidence in a confidence interval. Options A, B, and C either do not address the need for increased confidence or are detrimental to the accuracy of the data. Thus, option D stands out as the most effective strategy for achieving a more reliable estimate in research.