Correlation Flashcards
Expression of the degree and direction of correspondence between 2 things
Correlation
Linear relationship between only 2 variables, usually continuous in nature
Coefficient of correlation (r)
A widely used statistic for obtaining an index of the relationship between two variables when the relationship between the variables is linear and when the two variables correlated are continuous (that is, theoretically can take any value)
Pearson r
Significance at .05 means…
The result could have been expected to occur by chance alone 5 times or less in a hundred
Mean for the sum of products is calculated, and mean is the value of “r”
Pearson r
A value indicating how much variance is shared by two variables being calculated.
Coefficient of determination
Square of the correlation coefficient and multiply by 100
Coefficient of determination
R-squared tells you how much of the variation in your Y-values (predicted values) can be explained by variation in your X-variables (predictor variables)
Coefficient of determination (r squared)
A deviation about a mean of distribution
moment (product-moment coefficient of correlation)
Individual deviations about the mean of a distribution
Deviates (product-moment coefficient of correlation)
Multiplication of 2 corresponding standard scores can therefore be comceptualized as one that entails the computation of he product of corresponding moments
Product (product-moment coefficient of correlation)
Also known as rank-order correlation coefficient
Spearman rho
This index of correlation may be the statistic of choice when the sample size is small (less than 30) and both sets of measurements are interval or ordinal; non-parametric version of Pearson r
Spearman rho
A graphic description of correlation achieved by graphing the coordinate points for the two variables.
Scatterplot/scatter diagram/bivariate distribution
What is curvilinearity?
How curved a graph is (eyeball gauge)
An extremely atypical plot point in a scatterplot; any extremely atypical finding in research
Outlier
The analysis of relationships among variables to understand how one variable may predict another
Regression
Represented by a specific value of a and b is fitted precisely to the points on the scatterplot so that the sum of the squared vertical distances from the points to the line will be smaller than any other line that could be drawn to predict one score variable
Regression line
In regression, an error in the prediction of Y from X; the lower the degree of correlation, the higher the standard error of the estimate
Standard error of estimate (SEE)
The analysis of relationships between more than one independent variable and one dependent variable to understand how each independent variable predicts the dependent variable
Multiple regression
If ang usa ka predictor kay di correlated sa other predictors but correlate sa Y, then mas naay weight kay sa sa 2 predictors na highly correlated to each other because redundant na sya, thus less weight to prediction to Y (also take into account correlations among predictors (X) dili ra correlation sa ipredict (Y)
To remember sa multiple regression
A family of techniques used to statistically combine info across studies to produce single estimates of the statistics being studies; value depends on the skill and ability of meta analyst
Meta-analysis
Also referred to as a cutoff score, a reference point, usually numerical, derived as a result of judgment, used to divide a set of data into two or more classifications, with some action to be taken or some inference to be made on the basis of these classifications
Cut score
Know about the culture of testaker and era of testtaker experienced
Culturally informed assessment
A dichotomous variable that naturally form 2 categories
True dichotomous
A dichotomous variable that reflect an underlying continuous scaled forced into a dichotomy (e.g.range of scores na makapass or fail in an exam)
Artificially dichotomous
Expresses the relationship between a continuous variable and an artificial dichotomous variable
Biserial correlation
True dichotomous and continuous variable
Point biserial correlation
artificial dichotomous and true dichotomous
Phi coefficient
Both artificial dichotomous variables
Tetrachoric r
Continuous to continuous variables
pearson r
