correlations Flashcards
what are correlations
it means association - it is a measure to the extent of which two co-variables are related
what is a positive correlation
an increase in one variable associated to an increase in the other variable
what is a negative correlation
an increase in one variables associated with a decrease in the other
what is a zero correlation
no relationship between variables
what is a prediction
if there is a relationship between two variables we can make predictions about one from another
what is validity in correlations
concurrent validity-correlation between a new measure and an established measure
what is reliability in correlations
test-retest reliability - inter-rater reliability
what is theory verification
predictive validity
how can we measure a correlation
we can express it numerically as a coefficient ranging from -1 - +1
what does the correlation co-efficient indicate
the extent to which pairs of numbers for these variables lie on a straight line. values over zero indicate a positive correlation while values under zero indicate a negative correlation.
what is a perfect negative correlation
-1
what is a perfect positive correlation
+1
