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6 years ago in Data Analysis By Pragati

Determining sample size from unknown population

If you want to determine the sample size from the unknown population then compute the minimum sample size you require, 
choose a standard normal deviation, select a response value and confidence interval. 
Then calculate the required sample size by using the formula, n = z 2 (p)(1-p)/c2
Where c is the confidence interval, p is the response and z is the standard normal deviation

All Answers (3 Answers In All)

By Nirav Answered 6 years ago

If you want to determine the sample size from the unknown population then compute the minimum sample size you require, 
choose a standard normal deviation, select a response value and confidence interval. 
Then calculate the required sample size by using the formula, n = z 2 (p)(1-p)/c2
Where c is the confidence interval, p is the response and z is the standard normal deviation

By Vipul Answered 6 years ago

To calculate the sample size you determine the target population size, margin of error, standard deviation and confidence level. 
On identifying these values, you can calculate sample size by using the formula
Sample size = (Z-score)2 * StdDev*(1-StdDev) / (margin of error)2
The confidence level corresponds to z-score

By Pooja Answered 6 years ago

Margin of error is nothing but confidence interval. It identifies how much lower or higher than the population mean the sample falls.

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