November 15, 2012.
Lecture 8 – Sampling Distribution of the Mean
What is a sampling distribution?
Helps us evaluate the statistic from our sample
Matched to a statistic
All possible values blah blah blah seen this slide before…
Generating a Sampling Distribution
Probability Approach: uses basic probabilities
Empirical Approach: uses an actual or theoretical set of population scores that exist if the IV has
Let’s define population of 400 unbiased coin flips
o A priori probability: 50% heads
Null-Hypothesis Population of Coin Flips
General Characteristics of the Sampling Distribution of the Mean, for any N
It’s a frequency distribution of means
o Those means are calculated by drawing all possible samples of N sized samples from the
null population, calculating the mean for each sample, and plotting it.
It contains all values the mean can take
Its mean equals