Joshua Weller|Nathan F. Dieckmann|Martin Tusler|C. K. Mertz|William J. Burns|Ellen Peters
Development and Testing of an Abbreviated Numeracy Scale: A Rasch Analysis Approach
Decision Research|Decision Research|The Ohio State University|Decision Research|Decision Research|The Ohio State University
abstract research demonstrated individual differences numeracy may important consequences decision making present paper develop shorter psychometrically improved measure numeracythe ability understand manipulate use numerical information including probabilities across two large independent samples varied widely age educational level participants completed 18 items existing numeracy measures study 1 conducted rasch analysis item pool created eightitem numeracy scale assesses broader range difficulty previous scales study 2 replicated eightitem scale separate rasch analysis using data independent sample also found new raschbased numeracy scale compared previous measures could predict decisionmaking preferences obtained past studies supporting predictive validity study 3 established predictive validity raschbased numeracy scale specifically examined associations numeracy risk judgments compared previous scales overall found raschbased scale better linear predictor risk judgments prior measures moreover study first present psychometric properties several popular numeracy measures across diverse sample ages educational level discuss usefulness advantages new scale feel used wide range subject populations allowing clear understanding numeracy associated decision processes copyright 2012 john wiley amp sons ltd