12. Sampling error is assumed to result: a. when any sample is selected b. only when a non-representative sample is selected c. only when a biased sample is selected d. only when the researcher makes a mistake 13. Any sample which contains fewer than 50% of the total population: a. must be biased c. must be inaccurate b. must be non-random d. none of these 14. The Central Limit theorem states that the sampling distribution of means is: a. only available by inference b. only available when sample sizes are less than 10 c, only available when the very high and very low means have been eliminated d. approximately normal in shape 15. When the standard deviation of the entire distribution of random sample means had been calculated, the resulting value is called: a. the deviation score c. the standard error of the mean b. the parameter mean d. sampling error 16. When comparing the size of the standard error of the mean with the size of the standard deviation of the underlying distribution of individual scores: a. the standard error of the mean is always larger b. the standard error of the mean is always smaller c. the standard error of the mean is sometimes larger and sometimes smaller, depending on the sample size d. none of these 17. The standard error of the mean must equal: a. the standard deviation of the sample's distribution of individual scores b. the standard deviation of the entire population's distribution of individual scores c. the "average" of the sample's distribution of individual scores and the population's distribution of individual scores d. the standard deviation of the entire sampling distributions of means 18. According to the text, the highest value that should be assigned to the alpha error is: a. .95 b. .99 c. .10 d. .05 19. If it is determined that there is no difference between the population mean being represented by the sample and the mean of the population at large, then: a. the alpha error must have been accepted b. the alpha error must have been rejected c. the alpha error must have been committed d. the null hypothesis must have been accepted 20. When a given difference is determined to be "significant",: a. then the alpha error must have been accepted b. then the alpha error must have been rejected c. then the null hypothesis must have been rejected d. then the null hypothesis must have been accepted