Statistical concept expressing the degree of confidence that, for instance, total losses will be below or above a given amount in any specified period, typically 1 year. The confidence level, or per [..]

A confidence interval for the difference between two means specifies a range of values within which the difference between the means of the two populations lies.

Means for stating numerically the level of confidence about a result

A confidence interval is an interval on a scale (e.g., score scale, percent scale) that indicates where the true value (e.g., average, percentage) most likely is located. Because NAEP is a survey with [..]

A range of values for a variable of interest, e.g., a rate, constructed so that this range has a specified Probability of including the true value of the variable.

A range of values for a variable of interest, e.g., a rate, constructed so that this range has a specified probability of including the true value of the variable.

All of the effect sizes produced by impact evaluations are estimates. Typically, confidence intervals provide the range of values that has a 95% probability of including the real effect size. The width of the confidence interval indicates the confidence we can place in a finding: the wider the interval, the less confidence we can have.

The range around a survey percentage, plus or minus, that is likely to contain the population parameter (the correct answer).

A confidence interval (CI) is a computed interval with a given probability (calculated at 95% probability in this report) that a true value of a variable, such as a rate, mean or proportion, is contained within the interval. The confidence interval is the likely range of the true value.