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Learning Complex Concepts. To decide if a stimulus is a member of a conceptual category, you have to see if the stimulus has certain attributes. These attributes define the concept. .
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Learning Complex Concepts To decide if a stimulus is a member of a conceptual category, you have to see if the stimulus has certain attributes. These attributes define the concept. You then apply a conceptual rule that tells you which attributes must be present or absent to say that the stimulus is a positive instance of the concept. The more attributes a concept involves, the greater is its logical complexity.
Learning Complex Concepts Cognitive researchers have traditionally studied more complex concepts than behavioral researchers. In addition, cognitive researchers have used a different kind of procedure for presenting stimuli: Instead of presenting the same series of stimuli across trials, as in the Kelleher experiment with chimpanzees, a new stimulus is presented on every trial. To make the correct response to a stimulus, the subjects must learn the concept; they can’t just “memorize the answers.”
Learning Complex Concepts Here’s what it’s like. You will be shown a series of faces. Each face consists of a set of attributes: Rounded Eyebrows Arched Eyebrows Open Eyes Closed Eyes Upturned Mouth Downturned Mouth Your problem: to decide whether each face you’ll see is a positive instance of the concept.
Learning Complex Concepts Only one attribute is relevant to solving the problem. Rounded Eyebrows Arched Eyebrows Open Eyes Closed Eyes Upturned Mouth Downturned Mouth When you see the face (stimulus), respond “Yes” if you think it’s a positive instance or “No” if you think it’s a negative instance.
Learning Complex Concepts After you make your response, you will see the answer. Rounded Eyebrows Arched Eyebrows Open Eyes Closed Eyes Upturned Mouth Downturned Mouth From Matlin, M. (1983) Cognition. New York: Holt, Rinehart & Winston.
Learning Complex Concepts The concept is “rounded eyebrows.” You can ignore all other attributes of the face and respond correctly to each new stimulus by looking only for the rounded eyebrows. The first four faces provide enough information to solve the problem. Here’s how: Going from Face 1 to Face 2: This shows that open and closed eyes are irrelevant since these were the only changes and the answer was still Yes.
Learning Complex Concepts The concept is “rounded eyebrows.” You can ignore all other attributes of the face and respond correctly to each new stimulus by looking only for the rounded eyebrows. The first four faces provide enough information to solve the problem. Here’s how: Going from Face 2 to Face 3: Both the eyebrows and the mouth have changed, so we can’t yet tell which change is responsible for the No answer. ....
Learning Complex Concepts The concept is “rounded eyebrows.” You can ignore all other attributes of the face and respond correctly to each new stimulus by looking only for the rounded eyebrows. The first four faces provide enough information to solve the problem. Here’s how: Going from Face 3 to Face 4: This shows that an upturned vs. downturned mouth is irrelevant. The answer stayed No when the mouth changed. We already knew that the change in eyes was irrelevant. The arched eyebrows did not change and the answer stayed No. So rounded eyebrows are needed for a Yes answer.
Learning Complex Concepts Concept learning is divided into two subprocesses: attribute learning and rule learning. Attribute learning is the process of discovering the relevant attributes of a concept. Rule learning is discovering whether the attributes must be present or absent. The demonstration with the faces would be an example of __________learning. attribute Here’s a demonstration of rule learning where you know in advance which attributes of the stimulus are relevant to the concept (Matlin, 1983).
Learning Complex Concepts On each trial you will see a house with two relevant attributes: a chimney a window An attribute may be present or absent. What rule determines whether a house is a positive instance of the conceptual category?
Learning Complex Concepts Positive Instance? YES 1
Learning Complex Concepts Positive Instance? YES 2
Learning Complex Concepts Positive Instance? NO 3
Learning Complex Concepts Positive Instance? YES The rule is ...? 4
Learning Complex Concepts If the house has a chimney, it must also have a window. Any house without a chimney is also a positive instance. This is known as the conditional rule, or implication: the presence of one attribute implies the presence of another. In the next presentation we will look at rules at three levels of logical complexity and see how complexity relates to the difficulty of learning the concept.
