Slide 8 of 25
Notes:
- On the basis of observing the sample, the researcher makes generalizations to the population.
- When we select a sample in order to make a statement about a population on a given dimension (for example, the average number of children), we want to ensure we are using a representative sample of the population. If the population has 60% males and 40% females, we want our sample to reflect this. Do not want a biased sample that will lead us to erroneous statements about the population.
- One procedure for approximating a representative sample is random sampling. Random has very precise meaning in scientific discourse. As applied to sampling problems, essential characteristic of random sampling is that every member of the population has an equal chance of being selected for the sample.
- Random sampling is an ideal that is seldom achieved in practice.
- Use of random sampling does not guarantee that sample will be representative of the sample.
