Validity of Information Display Boards: An Assessment Using Longitudinal Data
An experiment was done in which subjects acquired information on, made choices among, and consumed their choices of five health breads once a week for six weeks. Information acquisition was monitored by means of an information display board (IDB). Validity of the method was assessed by comparing actual information acquisition with hypotheses based on theory and/or empirical evidence. This method showed reasonable construct validity. The amount of information acquired declined significantly between each pair of adjoining choice occasions. The introduction of a new brand in the fourth week did not increase total acquisition, but shifted the search primarily to the new brand. Similarly, announcement of a price reduction on one bread did not increase total acquisition, but shifted information acquisition to the reduced-price brand and to the prices of the other brands.