PSYC 2501 Lecture Notes - Lecture 30: Mental Chronometry, Dependent And Independent Variables, Semantic Network
Knowledge categorization
Tuesday, April 10, 2018
12:35 PM
• How do we categorize things?
o Probably don't use definitions because they are too rigid, not all members of a
category have the same features
o Maybe we categorize using stored prototypes
• Evidence that we use prototypes to categorize
▪ Typicality effects
• Faster to say a robin is a bird than an ostrich is a bird
▪ Process highly prototypical items differentially
▪ Process highly prototypical items preferentially
▪ Prototypicality affects priming
• Told to respond when you see green, respond faster when you
see a more prototypical green than when you see a light green
• CogLab: prototypes
o This experiment investigates whether we use prototypes to categorize
concepts
• It used a pattern of dots that were variations of two prototypes (A & B)
• Training phase (60 trials)
▪ Variants of prototype A
▪ Variants of prototype B
▪ Didn’t see prototypes in this phase !
• Test (16 trials)
▪ Prototype A (four times)
▪ Prototype B (four times)
▪ New variant of prototype A (four times)
▪ New variant of prototype B (four times)
▪ Did not see any of these during the training phase
• Prediction
▪ If we store prototypes in memory, then we should be faster at
classifying the never-before-seen prototypes than at classifying the
never-before-seen new variants
• Independent variable
▪ Which pattern you saw in the test phase: the prototype or the new
variant
• Dependent variable
▪ Reaction time at classifying the prototypes vs new variants
• Results
▪
find more resources at oneclass.com
find more resources at oneclass.com