Wolfram Research
Wolfram Math World: Probability and Statistics
This is a resource for many topics in probability and statistics. Click on the topic of your choice for an explanation. The sites you will be linked to are quite extensive. A degree of higher-level math is necessary for understanding...
Web Center for Social Research Methods
Research Methods Knowledge Base: Sampling in Research
Site discusses the use of sampling in research. The key statistical terms used in sampling are linked for the user to quickly find definitions. The major concepts of probability and nonprobability are also highlighted.
Other
University at Albany: Populations and Samples: The Principle of Generalization
This resource explains what generalization is in statistics, its advantages and disadvantages, and problems that can occur, e.g., sample or response bias. Includes detailed examples of sampling error and sample bias.
CK-12 Foundation
Ck 12: Statistics: Sampling Distributions
[Free Registration/Login may be required to access all resource tools.] This concept introduces the sampling distribution of the mean, inferring the population mean from samples and sampling error.
Shodor Education Foundation
Shodor Interactivate: Stats and Probability Concepts
Many topics on Statistics and Probability are defined and linked here. Click on any of them to move to a more detailed discussion of the term.