The null hypothesis attempts to show that no variation exists between variables, or that a single variable is no different than zero. It is presumed to be true until statistical evidence nullifies it for an alternative hypothesis.
The theory that, as sample size increases, the distribution of sample means of size n, randomly selected, approaches a normal distribution.
The statistic or number determined by squaring the correlation coefficient. Represents the amount of variance accounted for by that correlation.
A sample in which every element in the population has an equal chance of being selected