1、概念与分类(Concept and categorization),概念的本质分类是将近似的物体、时间、模式分门别类。概念则是这些类别的心理表征。概念可以帮助我们组织知识,将新遇到的事物与旧事物联系起来。,分类的作用,Why categories are useful?Knowing something is in a category provides a great deal of information about it.,五大流派,两大阵营,对于概念的理解有五大流派:经典理论原型理论样例理论图式理论基于知识的理论它们又被分为两个大的阵营:基于相似派和基于解释派。,基于相似派(simil
2、arity-based category),包括:经典理论原型理论样例理论图式理论的某些部分基本观点:认为人们根据样例相对于类别的某种抽象形式(例如定义或原型)的相似性进行分类;或者根据新样例相对于其他已经储存于记忆中的样例的相似性进行分类。,基于解释派(explanation-based category),包括:图式脚本理论的某些部分基于知识的理论基本观点:认为人们总是在样例和类别之间有意义的关系的基础上对样例做出分类。,经典理论( the classical view),观点:任何一个概念都是由一系列必要的和充分的特征加以定义的: the classical view holds tha
3、t the features represented are individually necessary and collectively sufficient (Medin, 1989). 概念不是由样例作为表征,而是由特征信息的抽象形式作为表征的,类别的成员泾渭分明,没有较好或较差的样例。 The classical view has no way to explain peoples intuitions that some birds are “birdier” than others.,样例的隶属程度评价,Rosch: Typicality ratings for members
4、of two categories,原型理论(The Prototype View ),观点:人们在进行分类的时候,将事物与心理抽象物做比较,而这个心理抽象物就是原型,它是某类事物的理想化的表征。概念的家族相似性(family resemblance):不同成员之间有相似之处,也有不同之处。最典型的样例就是具备最多共同特征的样例。,样例(examplar)与原型(Prototype),family resemblance,The Prototype View,样例不一定具有概念的所有特征。家具(椅子、沙发具备较多的家具特征;钟、电话较少具备)番茄是蔬菜还是水果?(同时符合两个概念而造成分类困难
5、:当菜食用可谓之蔬菜,由花而结果可谓之水果),Some effects of prototypicality,Procedure for Roschs (1975) Priming experiment,Results for the conditions when the test colors were the same are shown on the right. (a) The persons “green” prototype matches the good green, but (b) is a poor match for the green.,原型理论的缺陷,概念没有明确的
6、界限;这与人们形成概念和使用概念的目的有关;隶属度(典型性)评价与上下文有关。鸽子在人民广场还是在打谷场,Medin et al.s (1982) “burlosis” experiment,Symptoms of burlosis (correlated condition),Medin et al.s (1982) “burlosis” experiment,Test cases Roger0111CorrelatedSusan1101Uncorrelated,样例理论(The Exemplar View ),观点:人们将具体的个别样本储存在记忆中,以后利用它们进行分类。The appro
7、ach assumes that people categorize new instances by comparing them to representations of previously stored instances, called exemplars.,样例理论的缺陷,与原型理论一样,概念没有明确的界限;样例最终被储存的标准?不同样例如何被提取?,Rosch的其他贡献,Basic Level Concepts:一种心理上认为是基本的概念,是求同和求异的妥协点,Basic Level Concepts,“Piano” and “guitar” are examples of t
8、wo basic-level categories. Such categories include members that are maximally similar to one another, unlike superordinate levels of categories (e.g., “musical instruments”), which contain members (e.g., pianos and guitars) that are dissimilar in several respects. At the same time, basic-level categ
9、ories are most differentiated from one another, especially relative to subordinate categories. “Grand piano” and “upright piano” are two categories at the subordinate level; these categories are less distinct than are two basic-level categories, such as “piano” and “guitar.”,图式脚本理论(The Schemata/Scri
10、pts View ),观点:图式脚本理论将概念看作图式,它包含一系列的信息,构成若干组成部分,这些信息可以作为缺省内容填补到情境中。Schemata exist for things bigger than individual concepts, however. Schemata fill in default values for some aspects of the situation unless other values are specified in the information itself. The filling in of these default values
11、allows us to make certain assumptions. Notice, however, that the default can be overridden simply by mentioning other values in the description of the situation.,基于相似理论的缺陷,Goodman (1972) 的议论: fork and spoon plum and lawnmower,基于解释的理论,观点:基于解释的理论认为,人们在分类活动中受到分类目的的指导。样例:children, pets, photo albums, fa
12、mily heirlooms, cash,概念形成理论面临的共同任务,在“经济性原则”与“信息量原则”之间求得平衡分类一致性(Some approaches, such as the classical approach, do this very directly; others have more fuzzy boundaries around and between concepts.),概念获得的策略,与认知研究的其他领域一样,应当认为人们加工信息的方式是灵活多样的,是随着情境和任务的目的而变化的。,概念获得的策略,Bruner, Goodnow and Austin(1956) 对于
13、概念形成策略的研究,Bruner实验材料,概念获得的策略,同时性扫描继时性扫描保守性聚焦赌胜性聚焦,原型的获得,原型的获得,原型策略(58)特征频率策略(28)样例策略(10)平均距离策略(4),非分析性概念形成,关键特征还是家族相似度?,概念形成的策略受到概念性质、样例和指导语等因素的影响概念学习组和简单再认组(后者更多用家族相似度),脚本的使用与形成,人们的脚本在内容上高度重合,在描述上高度一致;脚本起到补足情节的作用;脚本的代价是其他信息侵入记忆。,心理本质说,人们的一般行为似乎都是在承认物体、人、事件都有某种实质或潜在的本质,是它造就了事物的现象。实质限制了样例的变化范围。人们对于不同
14、类别的本质的知识帮助他们将深层特征和表面特征联系起来。在一般情况下,可以根据表面特征做出判断;但是当要研究细微差别时,需要专业知识。人们形成概念和表征概念的方式随着概念本身的特征而改变。不同种类的概念包含不同的信息。nominal-kind概念特征、natural-kind概念相似度、artifacts概念目的、功能。,概念与信息,nominal-kind 概念必要条件和充分条件natural-kind 概念本质特征;家族相似性artifacts 概念目的、功能,基于解释的理论。人们用不同的方式对待不同概念,关键在于归类的理由。,神经生理学研究,Category-specific neurons in the temporal lobe,