Coursera Learner working on a presentation with Coursera logo and
Coursera Learner working on a presentation with Coursera logo and

Statisticians use a confidence interval to describe the amount of uncertainty associated with a sample estimate of a population parameter.

How to Interpret Confidence Intervals

Assume that a 90% certainty interim expresses that the populace mean is more prominent than 100 and under 200. How might you translate this announcement? 

A few people think this implies there is a 90% possibility that the populace mean falls somewhere in the range of 100 and 200. This is off base. Like any populace parameter, the populace mean is a steady, not an irregular variable. It doesn’t change. The likelihood that a steady falls inside some random range is constantly 0.00 or 1.00. 

The certainty level portrays the vulnerability related with an inspecting strategy. Assume we utilized a similar examining technique to choose various examples and to figure an alternate interim gauge for each example. Some interim evaluations would incorporate the genuine populace parameter and some would not. A 90% certainty level implies that we would expect 90% of the interim appraisals to incorporate the populace parameter; a 95% certainty level implies that 95% of the interims would incorporate the parameter, etc.

Confidence Interval Data Requirements

To express a confidence interval, you need three pieces of information.

-Confidence level


-Margin of error

Given these information sources, the range of the confidence interval is defined by the sample statistic + margin of error. And the uncertainty associated with the confidence interval is specified by the confidence level.

Frequently the margin of error is not given; you must calculate it. Previously, we described how to compute the margin of error.