# Chapter 5 – Association and Causality

continuous variable
a type of variable that can have an infinite number of values within a specified range; e.g. height and weight.

method of difference
refers to a situation in which all of the factors in two or more domains are the same except for a single factor.

method of concomitant
refers to a type of association in which the frequency of an outcome increases with the frequency of exposure to a factor.

operationalization
refers to the process of defining measurement procedures for the variables used in a study.

inference
the process of passing from observations and axioms to generalizations.

point estimate
The value for the population is referred to as a parameter and the corresponding value for the sample is a statistic.

confidence interval estimate
A range of values that with a certain degree of probability contain the population parameter.

Statistical power
The ability of a study to demonstrate an association if one exists.

statistical significance
False positive rate = p value
P value represents the probability of detecting the association that you found
Less than 5% – statistically significant

need for causal inference
causal inference is more than relying on the statistics of one study