Biostatistics for the Clinician## Biostatistics for the Clinician

## University of Texas-Houston

Health Science Center## Lesson 2.1

## Sampling Distribution of Means

Lesson 2: Inferential Statistics 2.1 - 1

Biostatistics for the Clinician## 2.1 Sampling Distribution of Means

## 2.1.1 Why Important

In Lesson 1 you learned that there are two cases where you don't need to worry about statistics. When you have the whole population, and when you have large samples. Unfortunately, most medical experiments fall outside those. You typically have a small sample, and you typically want to generalize to a larger group. This is the job of inferential statistics.Actually, in the context above, the word "statistics" was being used in the more restrictive sense of inferential statistics or hypothesis testing statistics. Inferential statististical methods are the kind you use when you're trying to make inferences or generalize to the entire population based upon research that includes a small portion of that population.

Of course, you can always use the summary statistics or descriptive statistics of Lesson 1 to summarize or describe data where you're not trying to generalize beyond the group you've collected the data from. If you have quantitative data from any group, you can always find the mean, the median, and the mode. You can find the mean age or the standard deviation or any other of those descriptive measures. These are descriptive statististics. Descriptive statistics can be used to summarize group performance no matter what the size of the group and whether you have the whole group. a part of it, or anything else.