Sample space - answersThe set of all possible outcomes
Probability distribution - answersA full description of the probabilities of any outcome in
the sample space
Test statistic - answersAn observation or statistic calculated from a sample, used to
test a hypothesis
Product moment correlation coefficient (PMCC) - answersA statistic describing the
linear correlation between two variables. r represents the PMCC calculated from a given
sample. ρ ("rho") is the population PMCC - always express a hypothesis in terms of ρ (r
is the test statistic).
Actual significance level - answersThe probability of incorrectly rejecting the null
hypothesis (ie the chance that an observed result would fall in the critical region purely
by chance if the model assumed by the null hypothesis were true).
Binomial model - answersWhere there are a fixed number of trials; exactly two possible
outcomes; a fixed probability of success at each trial and trials are independent of each
other
Conditional probability - answersWhen the known occurrence of one event effects the
probability of subsequent events.
Continuity correction - answersAdjusting the values of discrete variables to their upper
and lower bounds when approximating with a continuous distribution such as the normal
distribution
Critical region - answersA region of the probability distribution which, if the test statistic
falls within it, leads to a rejection of the null hypothesis
Explanatory (independent) variable - answersThis variable could be controlled by the
researcher, and would usually be plotted on the x axis of a scatter graph
Extrapolation - answersMaking a prediction based on a value outside the range of the
given data
Hypothesis - answersA statement, which can be tested, about the value of a population
parameter
Interpolation - answersMaking a prediction for the dependent variable within the range
of the given data set
Regression line - answersA straight line, expressed in the form y = a + bx , calculated
to minimise the sum of the squares of the residuals