Margin of error in 2 minutes
Updated: May 19
I love statistics. Unfortunately, often statistics are made more complicated for the lack of a proper example.
Let me try to change it. Let's say I weight 90 kilograms. If I step on the scale tomorrow, what normal fluctuations can I expect? Exactly 90 kilograms is extremely unlikely. Is it +/- 2 kilograms?
That's what margin of errors tries to answer.
The formula for the margin of error is: critical value (z-score) x standard error
Let's say I want to be 95% confident. The critical value (z-score) is 1.96
The standard error is simply on standard deviation expressed in kilograms. Let's say it's 0.25 kilograms.
Therefore, the calculation is 1.96 * 0.25 = 0.49 kilograms.
Thus, I can be 95% confident, that my weight tomorrow is 90 kilograms +/- 0.49 kilograms.
Unless I did something unusual such as binging or fasting :-)