Toronto, May 10 (IANS) Knowing how long an unpleasant experience will last only makes it worse, researchers say.

 
 People assume that knowing the duration of a pleasant event will "kill the fun", but knowing how long an unpleasant event will last makes it tolerable.
 
 However, a new study contradicts this understanding, according to the Journal of Consumer Research.
 
 "Which is more enjoyable, knowing the exact duration of a dinner with a charming friend or not knowing it? What if the dinner is with disliked in-laws?" ask study authors Min Zhao and Claire I. Tsai, both from the University of Toronto.
 
 "Duration knowledge actually intensifies them, rendering a positive experience more pleasurable and a negative experience more aversive," the authors explain, according to a Toronto statement.
 
 The authors conducted a field study in a Taiwanese "cram school," an after-school programme designed to help middle school students meet academic goals.
 
 They told half the students that the session would last 60 minutes and told the other half that the session would be similar to after-hours sessions they had attended in the past (which varied from 30-90 minutes).
 
 "The results show that whereas students predicted that duration knowledge would improve their negative experience, in fact it rendered the experience worse," they said.
 
 The authors also conducted a lab experiment where participants listened to 30-second song clips sung either by a pop star or one of the researchers "who sings abominably".
 
 They found that people who knew the duration of the experience had more intense reactions in both directions.