Convenience sampling is a non-probability sampling method where participants are selected based on their easy accessibility or convenience, rather than their representativeness of the population.

The purpose of using a sampling frame is to ensure that the sample is representative of the population, meaning that the characteristics of the sample are similar to those of the population.

Systematic sampling is a probability sampling method where every $k$th element from the sampling frame is selected, where $k$ is determined by dividing the population size by the desired sample size.

A census involves collecting data from every member of the population, while a sample survey involves collecting data from a representative subset of the population.

Stratified sampling reduces sampling error by dividing the population into strata (groups) and selecting a sample from each stratum, ensuring a more representative sample.

Convenience sampling can lead to biased results because the sample may not be representative of the population, as participants are selected based on their easy accessibility rather than their representativeness.

A questionnaire is a quantitative data collection method that involves asking respondents a series of structured questions to gather numerical or categorical data.

A pilot study is conducted to test the feasibility of the research design, identify potential problems with the research instrument, and collect preliminary data, helping researchers refine their methods before conducting the main study.

Simple random sampling is a probability sampling method where every member of the population has an equal chance of being selected, ensuring an unbiased and representative sample.

A sample is a subset of a population, selected to represent the characteristics of the entire population.

A focus group is a qualitative data collection method that involves gathering a small group of people to discuss a particular topic or issue, allowing researchers to gain insights into their attitudes, beliefs, and experiences.

Cluster sampling is less expensive than other sampling methods because it involves selecting a few clusters (groups) from the population and then selecting all members within those clusters, reducing the cost of data collection.

Purposive sampling is a non-probability sampling method where participants are selected based on their expertise, knowledge, or experience related to the research topic, allowing researchers to gather in-depth information from specific individuals.

Systematic sampling can lead to biased results if there is a pattern in the data that coincides with the sampling interval, resulting in an unrepresentative sample.

Stratified sampling is a probability sampling method where the population is divided into strata (groups) based on a specific characteristic, and a sample is selected from each stratum in proportion to its size, ensuring representation of different subgroups.