What is the general term for sampling not based on probability that relies on knowledge or judgment?

What is the general term for sampling not based on probability that relies on knowledge or judgment?

• A. A non-statistical
• B. Simple random
• C. Stratified random
• D. Systematic grid

Answer: (A)

In sampling, you distinguish methods that rely on random selection (probability sampling) from those that rely on the investigator’s knowledge or judgment (non-probability or non-statistical sampling). When you choose units based on what you know about the situation, or pick convenient or specifically targeted sites because they’re most informative, you’re using a non-statistical approach. This captures the general term described: sampling not based on probability and driven by expertise or judgment. This approach is common in field work where a complete sampling frame isn’t available or when quick, focused insights are needed. It includes purposive or convenience selections, which are practical but can introduce bias and limit how well you can generalize findings to a larger population. The other terms imply some random component or a systematic scheme with known probabilities. Simple random, stratified random, and systematic grid all involve probability or a prescribed random-like process, which is not the case when the choice is driven by knowledge or judgment rather than a probabilistic rule.

In sampling, you distinguish methods that rely on random selection (probability sampling) from those that rely on the investigator’s knowledge or judgment (non-probability or non-statistical sampling). When you choose units based on what you know about the situation, or pick convenient or specifically targeted sites because they’re most informative, you’re using a non-statistical approach. This captures the general term described: sampling not based on probability and driven by expertise or judgment.

This approach is common in field work where a complete sampling frame isn’t available or when quick, focused insights are needed. It includes purposive or convenience selections, which are practical but can introduce bias and limit how well you can generalize findings to a larger population.

The other terms imply some random component or a systematic scheme with known probabilities. Simple random, stratified random, and systematic grid all involve probability or a prescribed random-like process, which is not the case when the choice is driven by knowledge or judgment rather than a probabilistic rule.