Abstract
In daily life one often has to subtract the time shown by an analogue display, e.g. a conventional watch, from a time presented digitally, e.g. in a time-table. In view of this discrepancy, speed and accuracy of mental subtraction from analogue and digital time displays with verbal reporting of the results were investigated with 20 subjects. For two digital displays, compared with either two analogue or one analogue and one digital display, subtraction speed was found to be twice as high whereas the error rate was lower. The errors for the three types of subtraction mentioned were classified into six categories. Operational and perceptual errors were typical of the analogue-analogue subtractions. For the digital-digital subtractions, typical errors were in mental arithmetic and digital-to-analogue conversion.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
