Uploaded January 2018 | Updated September 2026, 1 hour ago
A discussion of De Morgan's laws, in the context of basic probability. I illustrate De Morgan's laws using Venn diagrams, describe their meaning in a worded example, and show how they might be useful in a probability calculation.
I will get back to statistics videos in the not-too-distant future. Right now, I'm hammering away on probability for a little while.
A discussion of De Morgan's laws, in the context of basic probability. I illustrate De Morgan's laws using Venn diagrams, describe their meaning in a worded example, and show how they might be useful in a probability calculation.
I will get back to statistics videos in the not-too-distant future. Right now, I'm hammering away on probability for a little while.





![What Factors Affect the Margin of Error? (In a Confidence Interval for One Mean)
A look at the effect of various factors (the standard deviation, the sample size, and the confidence level) on the margin of error of a confidence interval for the population mean.
For those that use R, below I give the R code to find the values given in this video.
Z value for a 90% interval (see my other videos for a more detailed explanation of the rationale):
qnorm(.95)
[1] 1.644854
Z value for a 95% interval:
qnorm(.975)
[1] 1.959964
Z value for a 99% interval:
qnorm(.995)
[1] 2.575829 What Factors Affect the Margin of Error? (In a Confidence Interval for One Mean)](https://i.ytimg.com/vi/NQtcGOhUWB4/mqdefault.jpg)




