Thursday, 31 January 2019

Statistics MCQ's


╬  Inferential statistics is the:
A.        Process of using a population parameter to estimate the values for sample statistics
B.        Process of using sample statistics to estimate population parameters
C.        Process which allows the researcher to determine the exact values for population parameters
D.        Process that eliminates the problem of sampling error
E.         Branch of statistics involving using population parameters to estimate sampling distributions

╬         Which of the following statements are correct?
A.        A point estimate is an estimate of the range of a population parameter
B.        A point estimate is an unbiased estimator if its standard deviation is the same as the actual value of the population standard deviation
C.        A point estimate is a single value estimate of the value of a population parameter
D.        All of the above statements are correct
E.         None of the above statements are correct

╬         A point estimator is defined as:
A.        The average of the sample values
B.        The average of the population values
C.        A single value that is the best estimate of an unknown population parameter
D.        A single value that is the best estimate of an unknown sample statistic
E.         A number which can be used to estimate a point in time which is unknown

╬         Which of the following statements is/are correct?
A.        An interval estimate is an estimate of the range of possible values for a population parameter
B.        An interval estimate describes a range of values that is likely not to include the actual population parameter
C.        An interval estimate is an estimate of the range for a sample statistic
D.        All of the statements above are correct
E.         None of the statements above are correct

╬         A confidence interval is defined as:
A.        A point estimate plus or minus a specific level of confidence
B.        A lower and upper confidence limit associated with a specific level of confidence
C.        An interval that has a 95% probability of containing the population parameter
D.        A lower and upper confidence limit that has a 95% probability of containing the population parameter
E.         An interval used to infer something about an unknown sample statistic value

╬         The term 1 – α refers to the:
A.        Probability that a confidence interval does not contain the population parameter
B.        The level of confidence minus one
C.        The level of confidence
D.        The level of confidence plus one
E.         The level of significance

╬         A 95% confidence interval for the population mean is calculated to be 75.29 to 81.45. If the confidence level is reduced to 90%, the confidence interval will:
A.        Become narrower
B.        Remain the same
C.        Become wider
D.        Double in size
E.         Most likely no longer include the true value of the population mean

╬         A 95% confidence interval for the population mean is calculated to be 75.29 to 81.45. If the confidence level is increased to 98%, the confidence interval will:
A.        Become narrower
B.        Remain the same
C.        Become wider
D.        Double in size
E.         Most likely no longer include the true value of the population mean

╬         In the formula for the confidence interval, zα/2 is part of the formulA.      What does the subscript α/2 refer to?
A.        The level of confidence
B.        The level of significance
C.        The probability that the confidence interval will contain the population mean
D.        The probability that the confidence interval will not contain the population mean
E.         The area in the lower tail or upper tail of the sampling distribution of the sample mean