The procedure of assigning numbers to various degrees of opinion, attitude and other concepts is called

Assigning numbers to degrees of opinion and attitude is called scaling.

Scaling places qualitative concepts on a measurable numerical continuum.

Regression predicts one variable from another and is not this assignment.

Variance measures how spread scores are, not the act of numbering attitudes.

Concordance denotes agreement among rankings, not attitude measurement.

Common attitude scales include Likert, Thurstone and Guttman.