Summary of Formulae - Conditional Probability, Independent Events etc
This is only true if A and B are independent. You can never assume A and B are independent. You must either know it or prove it.
This is always true for two events A and B. The left hand side P(A divides B) is the probability that A will happen given that B has happened, often written as A given B or A conditional on B. If A and B are independent thenso
This is always true.
The above equations are very useful when working with Venn diagrams.
Correlation Coefficients and Regression Lines
If the equation of a regression line ofonis given bythenand
The unbiased estimate of the standard deviation of a random variablefound from a list of n numbersis given bywhere
If the expectation value – often called the mean, average, and writtenor– of a random variableis given byandthen
andfor all distributions, but if the distribution is continuous we may useand
andfor a continuous distribution etc.
for a continuous distribution.