Question

1. Which of the following describes the correct correlation between Confidence Percent Level and Margin of Error ‘E’:

A. As the confidence percent level of my CI increases (from 90% to 95% to 99%), the Margin of Error E decreases in value.
B. As the confidence percent level of my CI decreases (from 99% to 95% to 90%), the Margin of Error E increases in value.

C. As the confidence percent level of my CI increases (from 90% to 95% to 99%), the Margin of Error E also increases in value.

D. None

Answer 1

We know that the formula of Margin of error is directly proportional to the z-value of the problem; and thereby to the Confidence percent level.

This is also true in the intuitive sense, that when we want to be confident about our confidence interval, then the interval would evidently be larger, and the Margin of Error would also be larger.

So, this means that there is a positive correlation between confidence percent level and margin of error.

So, this means that, if the confidence level increases, then the margin of error must also increase.

This implies, the correct answer is option (C) As the confidence percent level of my Confidence Interval increases (from 90% to 95% to 99%), the Margin of Error E also increases in value.