QMB 3200 UCF FINAL VOCAB ALREADY PASSED

QMB 3200 UCF FINAL VOCAB ALREADY PASSED Parameter A numerical characteristic of a population, such as a population mean μ, a population standard deviation σ, a population proportion p, and so on. Target population The population for which statistical inferences such as point estimates are made. It is important for the target population to correspond as closely as possible to the sampled population. Sampled population The population from which the sample is taken. Sampling distribution A probability distribution consisting of all possible values of a sample statistic. Sample statistic A sample characteristic, such as a sample mean bar(x), a sample standard deviation s, a sample proportion bar(p), and so on. The value of the sample statistic is used to estimate the value of the corresponding population parameter. Finite population correction factor the term √((N-1)/(n-1)) that is used in the formulas for standard deviation of x bar and p bar whenever a finite population, rather than an infinite population, is being sampled. the generally expected rule of thumb is to ignore this when n/N ≤ .05 Simple random sample A simple random sample of size n from a finite population of size N is a sample selected such that each possible sample of size n has the same probability of being selected. Standard error The standard deviation of a point estimator. Point estimator The sample statistic, such as bar(x), s, or bar(p), that provides the point estimate of the population parameter. Central limit theorem A theorem that enables one to use the normal probability distribution to approximate the sampling distribution of bar(x) whenever the sample size is large. Point estimate The value of a point estimator used in a particular instance as an estimate of a population parameter. Unbiased A property of a point estimator that is present when the expected value of the point estimator is equal to the population parameter it estimates. Confidence interval Another name for an interval estimate. margin of error The ± value added to and subtracted from a point estimate in order to develop an interval estimate of a population parameter. Confidence coefficient The confidence level expressed as a decimal value. For example, .95 is the confidence coefficient for a 95% confidence level. Degrees of freedom A parameter of the t distribution. When the t distribution is used in the computation of an interval estimate of a population mean, the appropriate t distribution has n − 1 degrees of freedom, where n is the size of the sample. Confidence level The confidence associated with an interval estimate. For example, if an interval estimation procedure provides intervals such that 95% of the intervals formed using the procedure will include the population parameter, the interval estimate is said to be constructed at the 95% confidence level. Null hypothesis The hypothesis tentatively assumed true in the hypothesis testing procedure. Two-tailed test A hypothesis test in which rejection of the null hypothesis occurs for values of the test statistic in either tail of its sampling distribution.