Systematic favoring of certain responses over others, leading to underestimation or overestimation of a value.

Bias occurring when a sample comprises volunteers, potentially skewing results due to non-random selection.

Bias resulting from a portion of the population having a reduced chance of inclusion in the sample.

Bias when individuals chosen for a sample don't respond and differ from those who do.

Bias introduced when the wording of a question influences the response.

Sampling based on ease of access or availability, rather than random selection, leading to a non-representative sample.

Occurs when only volunteers participate, leading to over-representation of individuals with strong opinions.

Happens when some members of the population are inadequately represented in the sample.

Arises when a significant portion of those sampled do not respond, and they differ systematically from respondents.

The way a question is phrased can influence the answers given by respondents.

Selecting a sample based on easy accessibility, which often leads to a non-representative sample.

It leads to data and analysis that are not representative of the population, invalidating the results.

Voluntary Response: Participants choose to participate, often with strong opinions. | Convenience Sampling: Researchers choose participants based on ease of access.

Undercoverage: Some groups have reduced chance of selection. | Nonresponse: Selected individuals don't respond, differing from respondents.