# Dr. Dawn Wright

The Stats Files

## Why is the Standard Error Equal to Sigma Divided by the Square Root of n?

Every time I teach the Central Limit Theorem, I get questions from students on why we divide the population standard deviation, sigma, by the square root of the sample size to calculate the standard deviation of the sampling distribution which we call the standard...

## How to State the Conclusion of Your Hypothesis Test

The Easier Way After you have completed the statistical analysis and decided to reject or fail to reject the Null hypothesis, you need to state your conclusion about the claim. 1. To get the correct wording, you need to recall which hypothesis was the claim. If...

## Technology vs Tables and Rounding Mistakes

Joe, Two important points you bring up: Do not round intermediate values in a string of calculations. Wait until the very last step/answer to round to the number of decimals required by MyStatLab. On this problem and many others in this course, rounding too early can...

## Continuity Correction – Filling the cracks in the Normal Approximation to the Binomial

When we approximate a discrete distribution, such as the binomial, by a continuous distribution, such as the normal, we need to make adjustments so “things don’t fall in the cracks.” From the Central Limit Theorem, we know that a sample distribution from a population,...