What sample size is needed to give a margin of error of 1% with a 95% confidence interval?

A 90 percent level can be obtained with a smaller sample, which usually translates into a less expensive survey. To obtain a 3 percent margin of error at a 90 percent level of confidence requires a sample size of about 750. For a 95 percent level of confidence, the sample size would be about 1,000.

How can we get a smaller margin of error and still be at 95% confidence?

The margin of error at 95% confidence is about equal to or smaller than the square root of the reciprocal of the sample size. Thus, samples of 400 have a margin of error of less than around 1/20 at 95% confidence. To halve the margin of error at a given confidence level, quadruple the sample size.

How to calculate the margin of error with 95% confidence?

Therefore, the calculation of margin of error at a 95% confidence level can be done using the above the formula as, = 1.96 * 0.4 / √900. Margin Error at 95% confidence level will be-. Error = 0.0261.

What is the margin of error for p is estimate?

Margin of error: 0.04; confidence level: 95%; from a prior study, p is estimate Question 980618: Use the given data to find the minimum sample size required to estimate the population proportion. equivalent of 60%. You can put this solution on YOUR website!

How to find the margin of error for a population proportion?

Assume that a sample is used to estimate a population proportion p. Find the margin of error E that corresponds to the given statistics and confidence level. Round the margin of error to four decimal places. Use the given degree of confidence and sample data to construct aconfidence interval for the population proportion p.

What is the critical factor for a 95% confidence level?

For a 90% confidence level, the critical factor or z-value is 1.645 i.e. z = 1.645 Therefore, the error at a 90% confidence level can be done using above the formula as, Error = 0.0219 For a 95% confidence level, the critical factor or z-value is 1.96 i.e. z = 1.96