Sampling And Sampling Distribution by group 3.pdf
- 2. A sampling distribution of sample means is a frequency distribution using the means computed from all possible random samples of a specific size taken from a population. The means of the sample are less than or greater than the mean of the population.
- 3. SAMPLING ERROR • It is the difference between the sample mean and the population.
- 4. IMPORTANCE OF SAMPLING AND SAMPLING DISTRIBUTION Efficiency : Sampling allows researchers to gather data more efficiently and cost- effectively compared to studying the entire population. Generalizability : By carefully selecting a representative sample, researchers can generalize their findings to the broader population. Statistical Inference : Sampling distributions are crucial for making inferences about population parameters based on sample data. This allows researchers to test hypotheses and draw conclusions about the population.
- 5. There are two main categories of sampling: NON-PROBABILITY SAMPLING • In non-probability sampling, the selection of participants is not based on random chance. This can lead to bias, but it's often used in situations where probability sampling is impractical or impossible. PROBABILITY SAMPLING • In probability sampling, every member of the population has a known chance of being selected for the sample. This ensures a higher degree of representativeness and allows for statistical inferences about the larger population. TYPES OF SAMPLING
- 6. Steps in Constructing the sampling distribution of the means
- 7. STEP 1 : Determine the number of sets of all possible random samples that can be drawn from the given population by using the formula, Ncn, where N is the population size and n is the sample size. STEP 2 : List all the possible samples and compute the means of each sample
- 8. STEP 3 : Construct the sampling distribution. STEP 4 : Construct a histogram of the sampling distribution of the means.
- 9. EXAMPLE 1 A population consists of the numbers 2, 4, 9, 10 and 5. Let us list all possible samples size of 3 from this population and compute the mean of each sample.
- 10. EXAMPLE 2 Adrian Cedrick receives 82 or 83 as his grade on his three major subjects. Construct the sampling distribution of his mean grade.