Notes 7: Continuous Distributions

• The Poisson distribution has a single parameter $\lambda$
• The only distribution that is memoryless among continuous dist is the exponential.
• In a normal distribution the mean is the center of the curve and the variance is the spread of the curve.
• For a standard normal variable Z, the mean is 0 and the variance is 1.
• In a normal distribution the mean is the location of the normal.
• In a normal distribution the variance is the scale of the normal.
• In a normal distribution, a small $\sigma^2$gives a steep curve, and a large $\sigma^2$gives a flat curve.
• $\frac{x - \mu}{\sigma}$ is called the z-score.
• A z-score tells us how many standard deviations away from the mean an observation lies.
• $\phi (x)$ = normalcdf(-1000, x, -, 1)