STATISTICAL TECHNIQUES AND TOOLS
CONFIDENCE INTERVALS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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1.699
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0.56
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0.537
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19.325
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Detailed explanation-1: -For a margin of error of 5% and confidence level 95% you will need 356 respondents in total (see also our sample size calculator, spread proportionally across the schools. This is when you want to draw conclusions for your population in general.
Detailed explanation-2: -Step 1: Calculate the width of the confidence interval (a, b) by calculating b−a . Step 2: Calculate the margin of error based on the width of the confidence interval by dividing the width by 2: margin of error =b−a2 margin of error = b − a 2 .
Detailed explanation-3: -So the formula in order to determine the sample size is, n= ((z * )/MOE)2. In this formula, z is the z value obtained from the Z distribution table. is the population standard deviation of the data set. The MOE is the margin of error that is desired.