Sampling Methods and Bias

Which of the following is an example of a simple random sample?

• Selecting every 10th person who walks into a store

• Drawing names from a hat containing all the names of the students in a class

• Choosing the first 30 people who arrive at an event

• Interviewing people who volunteer in response to an advertisement

What is stratified sampling?

• Dividing the population into groups and selecting a sample from each group randomly

• Selecting samples based on convenience

• Choosing samples that volunteer themselves for the study

• Selecting every nth item from the population

Which of the following is a source of sampling bias?

• Randomly selecting phone numbers from a telephone directory

• Using a random number generator to select participants

• Stratifying the population before sampling

• Ensuring the sample size is large enough

Cluster sampling is best described as:

• Dividing the population into clusters and then randomly selecting some of those clusters to study

• Selecting every nth individual in the population

• Allowing the subjects to determine whether they want to be in the sample

• Dividing the population into strata and then sampling from each stratum

Which sampling method is most likely to result in a biased sample?

• Simple random sampling

• Stratified sampling

• Convenience sampling

• Cluster sampling

In the context of sampling, what does the term "population" refer to?

• The entire group from which a sample is drawn for a study

• The sample itself

• The geographical area where the study is conducted

• The number of individuals participating in the study

What is the main purpose of using stratified sampling over simple random sampling?

• To ensure that the sample is convenient to collect

• To reduce the cost of the study

• To ensure that specific subgroups within the population are adequately represented

• To increase the speed of data collection

Which of the following scenarios is most likely to use systematic sampling?

• A researcher wants to study the eating habits of high school students across the country.

• A factory quality control officer wants to inspect every 15th item coming off the assembly line.

• A political analyst wants to predict the outcome of an election by interviewing volunteers.

• A health official wants to assess the impact of a new drug by selecting patients randomly from a list.

What is the primary reason for avoiding the use of volunteers in sampling?

• It is too costly.

• It is time-consuming.

• It may lead to a biased sample because volunteers might not represent the entire population.

• It requires advanced technology.

When is it appropriate to use cluster sampling instead of stratified sampling?

• When the population is homogenous

• When the population is too large and spread out geographically

• When the researcher is studying a small, localized group

• When detailed information on subgroups of the population is needed