Análisis de las propiedades psicométricas de una escala de actitud : comparación de las técnicas Likert Y Thurstone

Abstract

The aim of this work was to compare “Thurstone” and “Likert” techniques for scale construction. To achieve this goal, two scales were ellaborated from both the same item set and sample of subjects and then scored and analysed according to either Likert’ or Thurstone’ procedure. Thus, thirty items were chosen for each scale, eightteen of them were shared. Reliability coefficients (") were higher for Likert-scale, even when responses were dichotomized. Regarding validity, correlation with an internal criterion was better for Likert than for Thurstone-scale, although factorial validity was not satisfactory in neither of them. Results confirm the adventages of Likert-scale and justify the masive use of it. These adventages could be, probably, due to the inclusion in the Likert-scale of items posited in the higher and lower end of the attitudinal continuum