PSYC 358 1st Edition Lecture 19Outline of Last Lecture II. Concepts and Knowledge Representationa. Multiple Levelsi. Superordinateii. Basiciii. Subordinateb. Taxonomic EconomyOutline of Current Lecture III. Concepts and Knowledge Representationa. Continuation of Last lecture’s conceptsCurrent LectureCognition4.2.15Day 19- Concepts and Knowledge RepresentationQOTD: How is knowledge organized and structured?(For Exam: pp 260- 271 wont be the basis for an essay question)- Do we have concepts that are restricted or do we have knowledge that represents ideas.o How much goes in the category and how much knowledge lies between the categories.The basic level and how knowledge affects categories (Rosch)- Some categories are privileged within a hierarchical organization (fig 9.8)o Basic is the best compromise between superordinate and subordinate. When we use thebasic level those categories are doing the best jobs of not just having their members be generally like each other, but also those members are distinct from other things that are not members of the category. These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Animal SUPERORDINATEDog Bear BASICCollie Poodle Grizzly Polar SUBORDINATE- Why have multiple levels? (fig. 9.9)o Property inheritance Don’t have to store the information at every single level. So if you know something is a dog and u know dog is an animal, things u stored about animals you can assume to be true about dogs, and can assume its true about poodles. So you don’t have to store that information for every single category and every single concept that you have. This is known as cognitive economy. o Difference levels are useful for different purposes Inferential power (# of common features) Within category similarity vs. between category difference - At the highest level of the superordinate you tend to find categories thatdon’t have too much within category similarity but they are uniquely separated from other kinds of things. So even though animals differ a lotfrom each other, the class of animals is distinct relative to all the other things that can exist in the world. Serves the purpose of distinguishing animal from other things rather than distinguishing different types of animals. When you look at a subordinate level, within the category there’s very little difference, so it does very little work to distinguish from other categories, cause there’s things that are similar to poodles that aren’t poodles but its doing a lot of work to say everything in that category is going to be very much alike. Evidence for the Basic Level (Rosch)- Lexicalization in languageo We don’t always have words at the more subordinate levels, but we always have words at the basic level. So our language itself has shaped itself around these cognitive constraints. - Naming performance (fig 9.10)o When you show people an object they tend to use the category and label for it at the basic level. So if you show a chair and say what is this, they don’t say what specific kind of chair it is, or say its furniture, they say it’s a chair. Its privileged cause when we see a thing, we identify it at the basic level. - Commonality of shape and partso Basic level was highest level where there was a commonality of shape and form and parts. So the physicality of objects tends to still be preserved at the basic level and if yougo any higher, than things start to get physically dissimilar. So the basic level is the highest level, most general level, where things seem to still be made of the same kinds of stuff.- Developmental order of acquisitiono Kids talk about the world first at the basic level. So we see the basic level is where things start, kids make sense of the world at the basic level. BUT, tends to vary systematically depending on:- Expertise (fig 9.11)o If you’re an expert, you don’t do the naming at the basic level. If you’re an expert on cars, and you see a car you wont say hey there’s a car. As you start to have more and more knowledge about something you get a shift in what level is privileged, so you become more natural in naming and organizing a world in terms of a more subordinate level. So car becomes a superordinate term that becomes very general for you. - Cultureo The Itza Maya tend to categorize more like U.S. experts also, the cultures project inferences differently  Less reliance on similarity based taxonomy Beyond the use of similarity for taxonomic categorization- Goal derived categories (Barsalou, 1983)o Not categories for dividing up different kinds of things in the world into diff types, they’re categories used to support our activities and the things were trying to accomplish in the world. o (e.g., pets, rewards…)o Graded membership, but violates family resemblance  Goodness based on central tendency around ideals- Ad- hoc categorieso Categories that are not our stabled regular ways of organizing knowledge, but they’re things we come up with on the fly that are systematic and do important work. If you’re in a situation where you need to bang on something but don’t have a hammer. Or your house is on fire, what do you want to take out of the house? o “Things to use instead of a hammer”o Things to take out of house in case of fire” Aren’t a set of things that are naturally coherent by your default way of deciding what’s similar. They are only coherent relative to this goal. Relative to the ideals that are the things that best support meeting the goal. o Goal derived categories can be generated on- line Not necessarily based on stored examples from experience - Relational categorieso Based on a certain relationship between thingso Tend to be abstract, but are cross cutting so all the things that are obstacles don’t have to be anything like each other. They don’t have a core default broad similarity  E.g., boundary, revenge Problems with Categorizing by Resemblance- The ‘pizza vs quarter’ study (Rips, 1989)o Imagine a three inch round object Is it more similar to a pizza or a quarter?- Most people would say quarter Is it more likely to be a pizza or a quarter? - Most people would say pizzaPeople think this 3 inch round object is more like a quarter, but is more likely to be a pizza. The most conservative claim you can make would be that when people are thinking about