Podcast
Questions and Answers
What is the relationship between sample size and sampling error?
What is the relationship between sample size and sampling error?
- As sample size decreases, sampling error increases.
- As sample size decreases, sampling error decreases.
- As sample size increases, sampling error decreases. (correct)
- As sample size increases, sampling error increases.
If a survey has a margin of error of 4.2 percentage points, what does this imply about the population proportions?
If a survey has a margin of error of 4.2 percentage points, what does this imply about the population proportions?
- The population proportions could differ by ±4.2% from the sample proportions. (correct)
- The population proportions could differ by ±8.4% from the sample proportions.
- The population proportions are expected to be within 4.2% of the sample proportions.
- The population proportions are expected to be exactly 4.2% different from the sample proportions.
How does the level of confidence affect the margin of error?
How does the level of confidence affect the margin of error?
- Confidence levels do not affect the margin of error.
- Higher confidence levels result in larger margins of error. (correct)
- Higher confidence levels result in smaller margins of error.
- Lower confidence levels result in larger margins of error.
What impact does a small sample size have on sampling error?
What impact does a small sample size have on sampling error?
Why do managerial issues influence sample size in probability samples?
Why do managerial issues influence sample size in probability samples?
How does the number of subgroups analyzed affect sampling error?
How does the number of subgroups analyzed affect sampling error?
What is the purpose of determining the sample size based on budget available?
What is the purpose of determining the sample size based on budget available?
Why is it crucial to consider confidence level when determining the margin of error?
Why is it crucial to consider confidence level when determining the margin of error?
What does a 90% confidence level imply about the range of results obtained?
What does a 90% confidence level imply about the range of results obtained?
What is a key consideration when determining whether a sample size is adequate?
What is a key consideration when determining whether a sample size is adequate?
What is the relationship between sample size and sampling error?
What is the relationship between sample size and sampling error?
How does the level of confidence affect the margin of error?
How does the level of confidence affect the margin of error?
Why do managerial issues influence sample size in probability samples?
Why do managerial issues influence sample size in probability samples?
What impact does a small sample size have on sampling error?
What impact does a small sample size have on sampling error?
How does the number of subgroups analyzed affect the accuracy of results?
How does the number of subgroups analyzed affect the accuracy of results?
What does a 90% confidence level imply about the margin of error?
What does a 90% confidence level imply about the margin of error?
Why is it crucial to consider budget availability when determining sample size?
Why is it crucial to consider budget availability when determining sample size?
What is the purpose of determining sample size based on past experience or client input?
What is the purpose of determining sample size based on past experience or client input?
How do financial considerations play a role in determining sample size?
How do financial considerations play a role in determining sample size?
What is significant about having a 95% confidence level when calculating margins of error?
What is significant about having a 95% confidence level when calculating margins of error?
What is the relationship between sample size and sampling error?
What is the relationship between sample size and sampling error?
Why is it essential to consider the confidence level when calculating margins of error?
Why is it essential to consider the confidence level when calculating margins of error?
How does budget availability typically influence sample size determination?
How does budget availability typically influence sample size determination?
Why does the number of subgroups analyzed pose a challenge in interpreting the results?
Why does the number of subgroups analyzed pose a challenge in interpreting the results?
What impact does a small sample size have on the margin of error?
What impact does a small sample size have on the margin of error?
Flashcards are hidden until you start studying
Study Notes
Determining Sample Size for Probability Samples
- The process involves financial, managerial, and statistical issues.
- Larger samples lead to smaller sampling errors and margins of error.
- Margin of error is a confidence interval around the sample statistic within which the population parameter is expected to be.
- It measures how many percentage points the results differ from the real population value.
Managerial Issues
- Managerial issues influence sample size based on confidence in including true population values in the chosen confidence interval.
- A survey with a 3.1 percentage point margin of error means the population proportions are expected to be within +/- 3.1 percentage points from the sample proportions.
- Managers must consider whether a 6.2 percent range is acceptable.
Budget Availability
- Budget availability sometimes determines sample size, which is not a scientific approach.
- Clients may specify the sample size they want (e.g., 100, 200, 300, 400, 500, etc.) based on past experience or personal judgment.
- Researchers must determine whether the requested sample size is adequate and inform the client.
Number of Subgroups Analyzed
- Sample size affects the accuracy of subgroup analysis.
- As sample size gets smaller, sampling error increases, making it harder to determine whether differences between groups are real or due to sampling error.
Confidence Level
- Confidence level is the probability that a particular interval includes the true population value.
- Margin of error is usually produced for one of four confidence levels: 99%, 95%, 90%, or 85%.
- A 95% confidence level means the true percentage for the population will be within the margin of error 95% of the time.
Margin of Error Example
- A survey found 45% of respondents would vote for Candidate A and 42% for Candidate B with a 3% margin of error and 95% confidence level.
- This means we can be 95% confident that support for Candidate A in the population is 45% +/- 3% (42% - 48%).
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
