In statistics, interval estimation is the use of sample data to calculate an interval of possible values of an unknown population parameter; this is in contrast to point estimation, which gives a single value. • In general, the confidence level is 1 -α. This is a new concept which is the focus of this lesson. • Developed from a sample • For a given confidence level • A confidence level C is a measure of the degree of reliability of the interval. Such intervals are built around point estimates which is why understanding point estimates is important to understanding interval estimates. p^ is a sample mean, a well-behaved estimator that inherits the properties of the SRS ) Ave(x p) = 0 and few x’s far from p August 14, 2020 4 / 14. Point Estimate Lower Confidence Limit Upper Confidence Limit Confidence Intervals • Provides a range of plausible values for a parameter. Interval Estimation for a Binomial Proportion Abstract We revisit the problem of interval estimation of a binomial proportion. • Typical confidence levels: .95 or .99 or .90. A major advantage of using interval estimation is that you provide a range of values with a known probability of capturing the population parameter (e.g., if you obtain from SPSS a 95% confidence interval you can claim to have 95% confidence that it will include the true population parameter. Jerzy Neyman (1937) identified interval estimation ("estimation by interval") as distinct from point estimation ("estimation by unique estimate"). 7.2 Interval Estimation of a Mean, Known Standard Deviation • A confidence interval is a range of probable values for a parameter. PROPERTIES OF INTEGRALS For ease in using the definite integral, it is important to know its properties. We revisit the problem of interval estimation of a binomial proportion. PI. The erratic behavior of the coverage probability of the standard Wald confidence interval has previously been remarked on in the literature (Blyth and Still, Agresti and Coull, Santner and others). Tolerance Intervals • Want to find an interval that captures certain percentage of the values in a normal distribution • Allow some uncertain factor (confidence level) • Tolerance interval for capturing at least k% of the values, with a confidence level 95% • Critical values … Interval Estimates Interval estimates give an interval as the estimate for a parameter. 6 Chapter 5: Interval estimation and testing 5.3 FURTHER PROPERTIES OF LARGE SAMPLES In order to understand the derivation of the conÞdence intervals in the pre-vious section, and of the statistical tests described in the next section, we must state and brießy explain two more properties of large samples. Next Estimating a Difference Score. Quiz: Point Estimates and Confidence Intervals Previous Point Estimates and Confidence Intervals. • A confidence interval has a confidence level. The erratic behavior of the coverage probability of the standard Wald confidence interval has previously been remarked on in the literature …