Sample Size Determination

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A guidance counselor wants to estimate the average age of all students enrolled in a barangay to public elementary schools. Determine the required sample size to construct a 99% confidence interval, assuming that the population standard deviation is 5.9 years based on past studies, and the length of interval must be 3.6.

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You want to estimate the population proportion of students who eat lunch at the school canteen. If you want to be 90% confident and the estimate must have interval length of 0.06, what is the sample size needed to attain the requirement if no preliminary estimate was given?

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You want to estimate the population proportion of students who eat lunch at the school canteen. If you want to be 90% confident and the estimate must have interval length of 0.06, what is the sample size needed to attain the requirement if based on previous survey, it is found that 28% prefer to eat lunch at school canteen?

Multiple Choice

What is the formula for determining the sample size when estimating the population mean?

• $$n=\frac{\left(z^2\cdot\sigma^2\right)}{E^2}$$

• $$n=\frac{\left(z^2\cdot\sigma\right)}{E}$$

• $$n=\frac{\left(z^2\cdot\sigma\right)}{E^2}$$

• $$n=\frac{\left(z\cdot\sigma^2\right)}{E}$$

Multiple Choice

Explain the concept of margin of error in the context of determining sample size for population mean estimation.

• The margin of error is the range of values within which the population mean is expected to fall.

• The margin of error is the level of confidence in the survey results.

• The margin of error represents the amount of random sampling error in a survey's results.

• The margin of error is the difference between the sample mean and the population mean.

Multiple Choice

What is the significance level and how does it affect the sample size calculation for estimating the population mean?

• It determines the color of the confidence interval

• It has no effect on the sample size calculation

• It is used to calculate the median instead of the mean

• It affects the sample size calculation by determining the critical value for the confidence interval.

Multiple Choice

Discuss the impact of population standard deviation on the sample size calculation for estimating the population mean.

• A larger standard deviation requires a larger sample size

• A larger standard deviation requires a smaller sample size

• A smaller standard deviation requires a larger sample size

• Standard deviation has no impact on sample size calculation

Multiple Choice

How does the desired confidence level influence the sample size determination for estimating the population mean?

• It only affects the margin of error but not the level of significance

• It only affects the level of significance but not the margin of error

• It affects the margin of error and the level of significance in the calculation of the sample size.

• It has no impact on the sample size determination

Multiple Choice

Explain the concept of power in the context of sample size determination for estimating the population mean.

• Number of participants in the study

• Probability of detecting a true effect

• 
  Standard deviation of the population

• Confidence level of the estimate

Multiple Choice

Discuss the factors that can affect the sample size calculation for estimating the population mean.

• Desired level of confidence, variability of the population, and margin of error

• Time of day the sample is collected

• Color of the population

• Number of people in the research team

Multiple Choice

What are the different methods available for determining the sample size for estimating the population mean?

• Asking friends and family

• Using a magic eight ball

• Guessing randomly

• Using a formula, using a sample size calculator, consulting statistical experts

Multiple Choice

What is the purpose of determining the sample size in a research study?

• To include the whole population in the study

• 
  To reduce the cost of running the study

• To make the study more complex and time-consuming

• To get accurate and statistically significant results

Multiple Choice

What does the term 'sample size' refer to in statistics and market research?

• The size of the entire population being surveyed

• he confidence level of the study

• The number of individuals included in the study

• The margin of error in the study

Multiple Choice

What is the purpose of using a confidence level in determining the sample size?

• 
  To increase the margin of error

• 
  To decrease the margin of error

• To make the study more complex

• To determine the probability that the actual mean falls within the margin of error

Multiple Choice

What is the purpose of using a margin of error in determining the sample size?

• To increase the confidence level

• To decrease the confidence level

• To make the study more complex

• To express the level of error in terms of mean numbers

Multiple Choice

What is the purpose of using a confidence interval in determining the sample size?

• To express the level of error in terms of mean numbers

• To make the study more complex

• To increase the margin of error

• To decrease the margin of error

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Mrs. Resabal wants to estimate the average age of all students from Barangay Marikaban who are enrolled in public schools. Determine the required sample size to construct a 99% confidence interval, assuming that the population standard deviation is 5.6 years based on past studies, and the length of interval must be 3.2.

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You want to estimate the population proportion of students who eat lunch at the school canteen. If you want to be 95% confident and the estimate must have interval length of 0.24, what is the sample size needed to attain the requirement if no preliminary estimate was given?

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You want to estimate the population proportion of students who eat lunch at the school canteen. If you want to be 95% confident and the estimate must have interval length of 0.24, what is the sample size needed to attain the requirement if based on previous survey, it is found that 34% prefer to eat lunch at school canteen?