Collecting Data

Limit the survey to those who have listed exercise as an interest on social media profiles.

Only call people during business hours on weekdays to ensure consistency in responses.

Use voluntary response where only interested individuals call back to give their answers.

Follow up with multiple calls at different times of day or days of week if there is no initial response.

Response bias, since respondents may not feel comfortable sharing truthful answers over the phone.

Undercoverage, because it misses segments of the population that do not have landlines.

Sampling variability, as results might differ from sample to sample even if they represent the same population.

Nonresponse, due to people refusing to participate in phone surveys.

Standard deviation

Range

Variance

Interquartile range

Undercoverage bias

Convenience sampling

Nonresponse bias

Voluntary response bias

Cross-validation using new data not included in model creation.

Replication of the models with the same initial dataset.

Confirmation of predictive accuracy using theoretical distributions only.

Assessment based on the highest R-squared value from initial results.

Results may be skewed by those who feel strongly enough to respond.

Respondents will provide socially desirable answers rather than honest ones.

Responses will be too varied to draw any conclusions.

Only positive feedback will be received, ignoring negative perspectives.

Convenience sampling

Undercoverage bias

Voluntary response bias

Nonresponse bias

Undercoverage bias

Response bias

Nonresponse bias

Voluntary response bias

Individuals who are chosen for a sample cannot or will not respond.

A question's wording influences the responses of an individual.

The individuals in a sample are selected based on availability, not with a random sampling method.

A portion of the population has a reduced chance of being included in a sample.

Undercoverage bias

Nonresponse bias

Response variance

Observer bias