The required sample size is. (Round up to the nearest integer. Would it be reasonable to sample this number of students? No. This number of IQ test scores is a fairly small number. OYes. This number of IQ test scores is a fairly small number. O Yes. This number of IQ test scores is a fairly large number. O No. This number of IQ test scores is a fairly large number.

P3. Show that the mle of unknown standard deviation when the mean is known is different from the sample standard deviation when the random sample is taken from a normal population characterized by two parameters, mean and variance. Which estimator is unbiased? Justify your answer. Show that a sample mean is a minimum variance unbiased estimator of the mean of a normal population with known variance.

Assume that we have made 10 repeated measurements of a quantity, and as a result the error assigned to the “best estimate” of the mean is 6. If we then expand our data set to a total of 20 measurements, the error in the mean will reduce to just 3. True or False

If we meet these conditions, the sampling distribution of the mean will have a normal shape and ... The mean of the sampling distribution will be u, (i.e., the same as the population mean) and the standard deviation of the sampling distribution will be (that's the population standard deviation divided by the square root of the sample size). In the AP Stats Guy video, he talks about the number of text messages his students send during class. Suppose the average number of text messages his students send during class is u = 30 text messages. If we take samples of say, n = 36 students at a time, we would expect the mean of the sampling distribution we create to be the same as the population mean, 30 text messages. If we can further say that standard deviation of the number of text messages is 12 text messages, by how much would we expect the sample means to vary? (hint, use the formula above) text messages