Semantic feature-comparison model: Difference between revisions

Revision as of 02:19, 4 July 2011

Latest revision as of 07:10, 20 January 2024

(31 intermediate revisions by 17 users not shown)

Line 1:

The '''semantic feature comparison model''' is used "to derive [[prediction]]s about [[categorization]] times in a situation where a subject must rapidly decide whether a test item is a member of a particular target category".<ref name=smith>Smith, E. E., Shoben. E. J., and Rips, L. J. (1974). Structure and Process in Semantic Memory: A Feature Model for Semantic Decisions. Psychological Review, 81(3), 214–241.</ref> In this [[semantic model]], there is an assumption that certain occurrences are categorized using its features or attributes of the two subjects that represent the part and the group. A statement often used to explain this model is "a [[European robin|robin]] is a bird". The meaning of the words ''robin'' and ''bird'' are stored in the memory by virtue of a list of features which can be used to ultimately define their categories, although the extent of their association with a particular category varies.

The '''feature-comparison model''' is a psychological theory of semantic memory hypothesized by Smith, Shoben and Rips (1974). The feature-Comparison model was purposed in contrast to the semantic network approach that was purposed by Collins and Quillian. The feature-comparison model is much simpler than the Collins and Quillian network in its structure, however it is also more elaborate in its assumptions about retrieval as well.

==History==

The Feature-Comparison model proposes that humans semantic memory works by the use of feature lists. Feature lists assume that semantic memory is a collection of lists of semantic features, which are simple, one-element characteristics or properties of the concept.

This model was conceptualized by Edward Smith, Edward Shoben and [[Lance Rips]] in 1974 after they derived various observations from semantic verification experiments conducted at the time. Respondents merely have to answer "true" or "false" to given sentences. Out of these experiments, they observed that people respond faster when (1) statements are true, (2) nouns are members of smaller categories, (3) items are "typical" or commonly associated with the category (also called prototypes), and (4) items are primed by a similar item previously given ([[University of Alaska Anchorage]], n.d.). In the latter item, respondents will respond faster to the latter statement since the category bird has been primed. Based on the previous observations, the proponents were able to come up with the semantic feature comparison model.<ref name=smith/>

==Theory==

An example that exemplifies the Feature Comparison model: When we (humans) think of a concept, like that of a robin, we unconsciously make a list of semantic features (for this example these would be things like animate, red-breasted, and feathered). These feature lists are then (unconsciously)ordered in terms of definingness, or priority, from top to bottom. The most defining features are located on the top of the list, while the lower features on the list are called the characteristic features, and they are features that are common but not essential to the meaning of the concept. In our example, the defining characteristics of a robin match the defining characteristics of a bird (animate, feathered, living), thus we are able to know that a robin is a bird. The more overlapping defining characteristics two things have, the quicker the retrieval will be between the two concepts. So when we are asked a question like "is a robin a bird?", we can quickly decide our answer and say yes because there are so many overlapping defining characteristics. These quick answers are called stage one responses. The reason that they are called stage one responses is because all that needs to be done to answer the question is a quick (still unconscious) feature comparison. If the two different things being compared are not so easily differentiated then a stage two comparison is needed. This stage two comparison is a comparison of defining features, in which a slower comparison is done with only defining features. An example of a question that would cause this would be "Is a chicken a bird", in which the reply is usually a slow "yes".

The cognitive approach consists of two concepts: [[information processing (psychology)|information processing]] depends on [[Mental representation|internal representations]], and that mental representations undergo transformations. For the first concept, we could describe an object in a number of ways, with drawings, equations, or verbal descriptions, but it is up to the recipient to have a background understanding of the context to which the object is being described in order to fully comprehend the deliverable. The second concept explains how memory can alter the way we perceive representations of something, by determining the sequence in which the information is processed based on previous experiences.

==Features==

The main features of the model, as discussed by Smith et al. (1974), are the defining features and the characteristic features. Defining features refer to the characteristics that are essential elements of the category, the non-negotiable, so to speak. For example, the 'bird' category includes such defining features as 'they have wings', 'feathers', 'they lay eggs', etc. Characteristic features refer to the elements usually found or inherent to category members but are not found in all, or non-essentials. For example, birds 'fly', – that is characteristic because while most birds fly, there are some who cannot.

The model has two stages for [[decision making]]. First, all features of the two concepts (bird and robin, in our example) are compared to find out how alike they are. If the decision is that they are very [[similarity (psychology)|similar]] or very dissimilar, then a true or false decision can be made. Second, if the characteristics/features are in-between then the focus shifts to the defining features in order to decide if the example possesses enough features of the category, thus, categorization depends on similarity and not on the size of the category.

==Evidence==

Evidence for Smith's Feature-Comparison Model come from his paper in which he asked people simple true/false questions and timed their decision time. The decision times matched predicted results for Smith's theories.

==Problems==

*Low [[ecological validity]]

*Does not account for [[fuzzy boundaries]] (unclear boundaries between concepts e.g. are bookends an item of furniture?)

*Limitation of category-membership judgements as a paradigm

*It is more likely that category membership is determined by [[family resemblance]] than by comparing lists of features

==References==

{{reflist}}

*University of Alaska Anchorage (n.d.). Cognitive Psychology – Memory Models, Knowledge Representation. Retrieved November 5, 2012 from http://www.math.uaa.alaska.edu/~afkjm/cs405/handouts/psycho.pdf

*Baddeley, A (1990). Human Memory. Welshpool, Wales: Lawrence Erlbaum Associates.

*Gazzaniga, Michael S., Richard B. Ivry, and G. R. Mangun. "Methods of Cognitive Neuroscience." Cognitive neuroscience: the biology of the mind. Third ed. New York: W.W. Norton, 1998. 111–112. Print.

[[Category:MemoryCognitive science]]

[[Category:Semantics]]