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.
Response Variable
Dependent variable
Explanatory Variable
Independent variable
Residuals
The differences between the observed values and those predicted by the regression line (line of best fit).
