The Sampling Distribution of a Sample Mean
Sampling Distribution of the Mean
Answers
- The mean of the sampling distribution of the mean is the mean of the
population from which the scores were sampled, in this case \(14\).
- The variance of the sampling distribution of the mean is the population
variance divided by \(N\). The population SD is \(6\), so the population
variance is \(36\). \(36/9 = 4\)
- The standard error is the standard deviation of the population divided by the square root of \(N\). In this case, \(12/4 = 3\)
- According to the central limit theorem, regardless of the shape of the
parent population, the sampling distribution of the mean approaches a
normal distribution as \(N\) increases. In this case, a sample size of \(30\) is
sufficiently large to cause the sampling distribution of the mean to
look about normal.
- Mean = \(75\), SD = \(2\), Skew = about \(0\): This problem is asking about the sampling distribution of the mean: Mean
= \(75\), SD = \(10/sqrt(25)\) = \(10/5\) = \(2\), Skew = about \(0\) because the central
limit theorem states that the sampling distribution of the mean would be
about normal with a large enough \(N\).