Correlation I
The type of numeric variable that must be used for both variables evaluated using correlation.
What is an equal-interval variable?
When calculating a Pearson correlation coefficient, raw scores for the X and Y variables must first be converted to these.
What are Z scores?
Pearson devised the Chi-square test to handle analyses of these.
What are nominal (or categorical) variables?
These are placed within parenthesis in each cell of a Chi-square matrix.
What are expected frequencies?
The type of graph used for visualizing correlation data.
What is a scatter diagram (or plot)?
The reason that degrees of freedom for correlations is calculated by subtracting 2 from the population sample size.
What is two means (or two variables)?
Type of Chi-square test employed when analyzing a single nominal variable.
What is a test for goodness of fit?
Values reported in the margins of each row and column of a Chi-square matrix represent these.
What are sums (or totals)?
The type of correlation that does not follow the general pattern of a line.
What is curvilinear?
It is common practice to use this type of test when determining the appropriate cutoff value during hypothesis testing for correlations.
What is a 2-tailed test?
Mismatch refers to the difference between these.
What are observed (O) and expected (E) frequencies?
In calculating the Chi-squared statistic, the squared differences are weighted according to this.
What is the (respective) expected frequency?
The slope of a line whose direction heads down and to the right denotes this type of correlation.
What is a negative correlation?
When hypothesis testing with correlations the null hypothesis assumes this value for 'r'.
What is r=0?
This is used to report a quantity for 'mismatch'.
What is the Chi-Square statistic?
In a 2x2 Chi-square matrix, each variable has two of these.
What are categories?
This is the result when one multiplies their Z score on one variable (X) by their Z score on another variable (Y).
What is a cross-product of Z scores?
The comparison distribution used when assessing whether a correlation coefficient is statistically significant.
What is a t distribution?
The name for the matrix of cells used for the Chi-square test for independence.
What is a contingency table?
The comparison distribution used for Chi-square tests.
What are Chi-square distributions?