next up previous
Next: Three Conventions Up: rev Previous: rev

Review of Chapter 7 in Wild and Seber

The main theme of Chapter 7 is:

The sample is not the population.
To keep this in mind, we distinguish
sample characteristics also called estimates.
and
population characteristics also called parameters.

Parameters are not random. There is only one population (in one particular application). Hence only one population mean, only one population standard deviation, and so forth. In real life, parameters are unknown quantities. You don't have population data. That's why you are using statistics on sample data.

Estimates are random variables. If the sample is random, then so are quantities (estimates) calculated from it. So, like any other random variable, an estimate has a probability distribution and a mean and standard deviation.



Subsections

Charles Geyer
2000-10-30