Definitions Flashcards
Factor
A variable which can only be a set of values (e.g. male or female).
Proportion
A part,share or number considered in comparative relation to a whole.
Null Hypothesis
The default expectation that there is no relationship between two measured phenomena.
Alternative Hypothesis
States that there is statistical significance between two variables.
Sample
A small subset of the population (that is supposed to be representative).
Population
All members of a defined group.
Sampling Error
The random variation introduced into a set of data as a function of only sampling a subset of the total population.
Measurement Error
The difference between a measured quantity and its true value. Includes random and systematic errors.
One-sided test
Experiment looking at just one thing (e.g. trying to prove there are more females than males)
Two-sided test
Experiment looking at two factors (e.g. and experiment checking for males to females ratio not being 1:1)
Chi-Squared Test
Measures how well the observed distribution of data fits with the distribution that is expected if the variables are independent.
P-Value
The probability that we would have observed a given deviation if the null hypothesis as correct (lower value means more statistical significance).
Type 1 Error
Occurs when the null hypothesis is actually true, but was rejected as false by the testing. A false positive.
Type 2 Error
Occurs when the null hypothesis is actually false but was accepted as true by the testing. False negative.
Regression Model
Describes the relationships between a Response variable and an Explanatory variable.
