SOLUTION: If you could help me w/ this problem I would really appreciate it! Why is a 99% confidence interval wider than a 95% confidence interval? Thank you!

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Question 1048816: If you could help me w/ this problem I would really appreciate it!
Why is a 99% confidence interval wider than a 95% confidence interval?
Thank you!
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

For a 95% confidence interval, we will look up the z values that separate the middle 95% of the area beneath the normal distribution from the remaining 5%. This remaining 5% is split between the right and left tails and half of 5% in each tail (i.e., 2.5% or .025). The z values that separate the middle 95% from the outer 5% are ±1.960 and our z multiplier is 1.960.
What if we wanted to be more conservative and use a 99% confidence interval? Now we need the z values that separate the middle 99% from the outer 1%. There will be 1% split between the left and right tails. The z values that separate the middle 99% from the outer 1% are ±2.58 and our z multiplier for a 99% confidence interval is 2.576.

The value of the multiplier+increases as the confidence+level+increases. This leads to wider intervals for higher confidence levels. We are more confident of catching the population value when we use a wider interval.