Normal
Typically used for measuraments clustered symmetrically around a mean.
- Notation
- $$N(\mu, \sigma^2)$$
- Range
- $$-\infty < x < \infty$$
- Probability mass function p(x)
- $$ \frac{1}{\sigma \sqrt{2 \pi}} exp\left(-\frac{1}{2}\left(\frac{x - \mu}{\sigma}\right)^2\right) $$
- Mean
- $$\mu$$
- Median
- $$\mu$$
- Mode
- $$\mu$$
- Variance
- $$\sigma^2$$
Code examples
Plot normal distribution in R
png(filename="normal-distribution.png") # Opens file
curve(dnorm, -3.5, 3.5, lwd = 1, axes = TRUE, xlab = "x", ylab = "y")
dev.off() # Closes png file