What Sample Size Do I Need To Be Statistically Significant. The size of your population will depend on your resources budget and survey method. For a test with 005 and 010 the minimum sample size required for the test is More often we must compute the sample size with the population standard deviation being unknown The procedures for computing sample sizes when the standard deviation is not known are similar to but more complex than when the standard deviation is known.
The amount of sway or potential error you will accept. Its the - value you see in media polls. A good maximum sample size is usually around 10 of the population as long as this does not exceed 1000.
Given your 10 acceptable error rate you can assume that if youd asked every person in your region to take your survey the actual proportion in favor of the longer school day would range from 60 to 80.
For example if you need 500 customers to respond to your survey and you know the response rate is 30 you should invite about 1666 people to your study 50030100 1666. Jun 16 2017 Confidence. Margin of Error or Confidence Interval. It is expressed as a percentage and represents how often the true percentage of the population who would pick an answer lies within the margin of error.
