diff --git a/education/statistics/Sampling.md b/education/statistics/Sampling.md index 7de8bc9..e38857f 100644 --- a/education/statistics/Sampling.md +++ b/education/statistics/Sampling.md @@ -34,6 +34,8 @@ An ideal sample will represent the whole population. | Response | When the question is worded in a leading way to elicit a certain response. | | Volunteer response | Self selecting, individuals volunteer to answer | | Measurement | Interviewing method influences the response, uses loaded words or ambiguities. | + +## Percentages (Ch 20, stat 1040) The expected value for a sample percentage equals the population percentage. The standard error for that percentage = `(SE_sum/sample_size) * 100%` @@ -43,4 +45,4 @@ To determine by how much the standard error is affected, if `n` is the sample si Accuracy in statistics refers to how small the standard error is. A smaller standard error means your data is more accurate. You can use the below equation to find the percentage standard error of a box model that has ones and zeros. the % of ones and zeros should be represented as a proportion (EG: `60% = 0.6`). -$$ \sqrt{\frac{(\% of 1)(\% of 0)}{num_{draws}}} $$ \ No newline at end of file +$$ \sqrt{\frac{(\%\space of\space 1s)(\%\space of\space 0s)}{num_{draws}}} $$(Ch 21, stat 1040) \ No newline at end of file