### abstract ###
according to the time-saving bias  drivers underestimate the time saved when increasing from a low speed and overestimate the time saved when increasing from a relatively high speed
previous research used a specific type of task - drivers were asked to estimate time saved when increasing speed and to give a numeric response - to show this
the present research conducted two studies with multiple questions to show that the time-saving bias occurs in other tasks
study  NUMBER  found that drivers committed the time-saving bias when asked to estimate a the time saved when increasing speed or b the distance that can be completed at a given time when increasing speed or c the speed required to complete a given distance in decreasing times
study  NUMBER  showed no major differences in estimations of time saved compared to estimations of the remaining journey time and also between responses given on a numeric scale versus a visual analog scale
study  NUMBER  tested two possible explanations for the time-saving bias  a proportion heuristic and a differences heuristic
some evidence was found for use of the latter
### introduction ###
if you need to complete a  NUMBER  km journey  how much time would it take at a mean speed of  NUMBER  kph
most people would find it easy to answer such a question -  NUMBER  km at  NUMBER  kph takes half an hour or  NUMBER  minutes
but what if you wanted to increase speed in order to reduce journey time
how much time would you save if you increase your speed to  NUMBER  kph or to  NUMBER  or  NUMBER  kph
many people consistently give the wrong answers to these questions
several studies have shown that people underestimate the time saved when increasing from a relatively low speed and overestimate the time saved when increasing from a relatively high speed  CITATION
