21. When an area (between high and low values) of the sampling distribution of means have been bracketed on the basis of a reasonable expectation of containing (estimating) the population mean, then: a. the Central Limit theorem has been proven b. the point estimate has been proven c. the alpha level has been calculated d. the confidence interval has been calculated 22. The true population mean is expected to fall outside a .99 confidence interval: a. 1% of the time b. 99% of the time c. 100% of the time d. none of these 23. Increasing the confidence-interval level from .95 to .99: a. increases the likelihood of including the population mean within its limits b. decreases the likelihood of including the population mean within its limits c. increases the number of degrees of freedom d. none of these, since a confidence level may never include the true population mean 24. The single-sample t ratio is used to compare: a. two population means b. a sample mean with an assumed or known population mean c. two sample means d. a single sample's mean with that same sample's standard deviation 25. Other things being equal, the higher the value of the t ratio: a. the greater the likelihood of rejecting the null hypothesis b. the less the likelihood of rejecting the null hypothesis c. the more certain that the samples represent a single population d. the greater the likelihood of a sampling error 26. Rejecting the null hypothesis when, in fact, it should have been accepted, causes the: a. standard error b. sampling error c. omega error d. alpha error 27. For the t ratio, the larger the sample size, the larger the: a. alpha error b. beta error c. number of groups d. number of degrees of freedom 28. For the t ratio, the larger the difference between the sample mean and the population mean (other things being equal), the greater the likelihood of: a. rejecting the null hypothesis c. sampling error b. accepting the null hypothesis d. committing the standard error 29. Whenever the calculated value of t is less than the tabled value of t (for a given number of degrees of freedom), then: a. the null hypothesis is accepted c. the null hypothesis is no longer relevant b. the null hypothesis is rejected d. the alpha error increases 30. The relationship between the alpha error and the confidence level is such that: a. the lower the alpha, the higher the confidence level b. the lower the alpha, the lower the confidence level c. they are not related until the confidence level reaches .95 d. none of these, since they are not related at all 3