Curves and Distributions
Important information from sections 6.1 and 6.2
Emprical Rule Graph
Empirical Rule:
For a distribution that is symmetrical and bell shaped (in particular, for a normal distribution):
1. Approximately 68% of the data values will lie within 1 standard deviation on each side of the mean
2. Approximately 95% of the data values will lie within 2 standard deviations on each side of the mean
3. Approximately 99.7% (or almost all) of the data values will lie within 3 standard deviations on each side of the mean
Z Score
Section 6.2
Section 6.2
The z value or z score (also known as standard score) gives the number of standard deviations between the original measurement x and the mean u of the x distribution