Consumer’s Product Knowledge

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2 LITERATURE REVIEW

2.1 Consumer’s Product Knowledge 2.1.1 Types of product class knowledge

Based on Brucks’ review of previous studies, consumer’s product class knowledge fall in to three categories: objective knowledge, subjective knowledge and the experience with the product (Brucks, 1985). The first category is objective knowledge.

It’s defined as what an individual actually knows or what is actually stored in the memory (Kanwar, Olson, & Sims, 1981; Russo & Johnson, 1980; Staelin, 1978). The second is the subjective knowledge, which is an individual’s perception of how much s/he knows (Gardner, 1984; Park & Lessig, 1981). The third is the amount of purchasing or usage experience with the product (Monroe, 1976; Marks & Olson, 1981). Before further discussion, we first eliminate the third category, which is the purchase/usage experience. Different people learn different things from similar experience. Even people have experience the same thing, they are likely to behave differently. The effect of experience toward search behaviors is inconsistent. Moreover, if consumer does not have any purchase or usage experience with the product, then nothing can be measure.

Therefore, experience-based knowledge is not considered as a good measure of product knowledge.

The measures of objective knowledge and subjective knowledge are conceptually and operationally distinct (Brucks, 1986). Since it’s difficult for people to perceive how much they actually know precisely, the differences between objective knowledge and subjective knowledge are predictable. Subjective knowledge can provide better understanding of decision maker’s systematic bias and heuristics (i.e. cognitive shortcuts) than objective knowledge (Park & Lessig, 1981). Furthermore, measures of

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subjective knowledge can represent one’s self-confidence as well as one’s objective knowledge (Park & Lessig, 1981). Perceived self-confidence is influential to one’s decision making behaviors. One lack of self-confidence in knowledge may conduct more or less searching activities in despite of one’s actual knowledge level. Thought it has not been empirically demonstrated, self-confidence is closely related to one’s decision making abilities (Brucks, 1986). In contrast, objective knowledge only reflects an individual’s actual knowledge level. Despite measuring subjective knowledge is easier than objective knowledge operationally, subjective knowledge indeed is a better predictor of behavior.

2.1.2 Prior product knowledge and information search

In the field of consumer information search, how prior product knowledge affect the amount of external information search was many researchers’ research subject.

Previous research findings related to the relationship between consumers’ prior product knowledge and information search were inconsistent. The research results could be roughly categorized into three types, which are positive, negative, and inverted U-shaped relationship. Every research finding was supported by reasonable explanations.

Till now the relationship between prior knowledge and search remains unclear.

2.1.3 Negative knowledge-search relationship

A number of studies showed that product knowledge and amount of information search is in negative relationship (Anderson, Engledow & Becker, 1979; Katona &

Mueller, 1955; Moore & Lehmann, 1980; Newman & Staelin, 1971, 1972; Swan, 1969;

Punj & Staelin, 1983; Beatty & Smith, 1987). That is the higher the knowledge they have, the less likely to search the product. For this result, one of the explanation was

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the de-motivation effect (Fiske, Luebbehusen, Miyazaki, & Urbany, 1994).

Knowledgeable consumer already has enough knowledge, so they don’t need to acquire more information before purchase (Punj & Staelin, 1983). Since these consumers perceive themselves having sufficient product knowledge, usually they are confident to their purchase decision as well (Bloch, 1986). In contrast, consumer lack of product knowledge would often lack of confidence to their knowledge and decision. This type of consumers are likely to engage information search (Bloch, 1986). Therefore the negative knowledge-search relationship was caused. Another explanation was that knowledgeable consumers search more efficient. They know what is the useful information, thence they search more efficiently. They abbreviate the searching process so they can use less time to find out the information they need. Since this kind of people can search within a short time, if we use search time to measure the amount of information search, the knowledge-search relationship would appear to be negative (Brucks, 1985).

2.1.4 Positive knowledge-search relationship

At the same time, some researchers postulated a positive relationship between product knowledge and external search (Brucks, 1985; Srinivasan & Ratchford, 1991;

Selnes & Troye, 1989; Moore & Lehmann, 1980). Positive relationship reflects the facilitating effect of knowledge (Fiske et al., 1994), which means prior knowledge can improve the efficiency of information collection (Alba & Hutchinson, 1987; Chi, 1981;

Punj & Srinivasan, 1989) and encourage more information search (Johnson & Russo, 1984; Bettman & Par, 1980; Brucks, 1985; Punj & Staelin, 1983). Comparing with common people, consumers with better understanding of the product can use lower cognitive cost to process information (Alba & Hutchinson, 1987; Fiske et al., 1994).

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“To ask a question, one must know enough to know what is not known” (Miyake &

Norman ,1979). Consumers with more product expertise also know more about what to ask and where to ask. Prior knowledge allow them to formulate more questions (Brucks, 1985). New information brings more benefit to the knowledgeable consumers, and encourage them to pursue more. In contrast, consumers lack of prior knowledge would not know how to start then only execute small amount of search (Brucks & Schurr, 1990).

2.1.5 The inverted-U shaped knowledge-search relationship

There existed some researches balance the above contrary findings by finding the non-linear inverted-U shaped relationship between prior knowledge and information search level (Bettman & Park, 1980; Hempel, 1969; Johnson & Russo, 1984). Inverted-U shape expresses a positive knowledge-search relationship from low-to-moderate knowledge level, and a negative relationship from moderate-to-high knowledge level.

It describes consumers lack of product knowledge don’t know how to start and where to search therefore seek less information, leading to the positive relationship. In contrast, consumers with product expertise, even they don’t pay much effort on searching, they can still make good purchase decision. The inverted-U shaped knowledge-search relationship gives possible explanation for the previous discrepancy, because when a linear line is applied on inverted-U shaped data, a positive or negative relationship, or no relationship at all may occur (Brucks, 1985). Inverted-U shaped knowledge-search relationship makes the divergent results from previous studies seem reasonable. Noted that some research experimentally tested the inverted-U shaped relationship but was not supported by the result (Brucks, 1985). A few studies demonstrated U-shaped relationship (Rao & Sieben, 1992), no relationship (Bennett & Mandell, 1969; Claxton,

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Fry, & Portis, 1974), or positive and negative relationship both exist but cancel out each other (Srinivasan & Ratchford, 1991).

Evidently, there existed great disparity among former studies. Given each study had reasonable explanation to their outcomes, the knowledge-search relationship remains uncertain and controversial. However, reexamine this relationship is not our purpose. We want to explore the knowledge-search relationship in different aspect that is the influence of knowledge on pre-purchase search and ongoing search. Maybe it could give new interpretation of the knowledge-search relationship.