Dr. Thomas P. Hogan, Professor of Psychology at The University of Scranton, presented a seminar on quantitative estimation ability.  Quantitative estimation involves the rapid estimation or approximation of numerical or physical quantities without the aid of measuring instruments, calculating devices, or exact counting.  The research literature on quantitative estimation generally distinguishes among three types: computational estimation, measurement estimation, and numerosity estimation.  Computational estimation involves rapid approximation of answers to algorithms such as 42 + 39 and 11/23 + 29/30, which could easily be answered exactly with a calculator, computer, or even paper-and-pencil given adequate time.  Measurement estimation involves providing rapid estimates of the measures of physical quantities involving length, weight, volume, time, distance, and areas, without the aid of measuring instruments, for example, estimating the height of a building or the weight of a book.  With measuring instruments, most of the measurement estimation tasks become simple.  Numerosity estimation involves providing estimates of the number of objects (e.g., dots) presented with very brief exposure time, usually one second or less.

Over the past several years we have produced 18 reports investigating one or more of these types of quantitative estimations, with 16 different University of Scranton undergraduate students serving as co-authors.  The studies have investigated the strategies people use in making estimations, the accuracy of the estimates, personality correlates of estimation ability, and the relationships among various estimation abilities and with other types of cognitive abilities.  One of our most recent reports compared performance of United States students with students in high performing countries around the world on estimation-type items in the Trends in International Mathematics and Science Study data base.  We are now extending that line of inquiry with the most recent international data, which includes about 400,000 students in 40 countries