Recovering Forgotten Information: a Study in Consumer Expertise

Elizabeth J. Cowley, University of Toronto
ABSTRACT - Consumer knowledge about a product class influences learning and remembering; processes active at both encoding and retrieval affect the designation of importance and ultimately, the accessibility of information. For the expert, more elaborate schema allows them to use their prior knowledge to more deeply encode information, and to access the information later with a rich network of cues. For the novice, the processes at encoding are less important. It is the processes at retrieval which influence whether or not information is remembered. The processes do not act independently, there is evidence of an interaction between encoding and retrieval processes. A study is presented which demonstrates the effects of knowledge on remembering product information.
[ to cite ]:
Elizabeth J. Cowley (1994) ,"Recovering Forgotten Information: a Study in Consumer Expertise", in NA - Advances in Consumer Research Volume 21, eds. Chris T. Allen and Deborah Roedder John, Provo, UT : Association for Consumer Research, Pages: 58-63.

Advances in Consumer Research Volume 21, 1994      Pages 58-63

RECOVERING FORGOTTEN INFORMATION: A STUDY IN CONSUMER EXPERTISE

Elizabeth J. Cowley, University of Toronto

ABSTRACT -

Consumer knowledge about a product class influences learning and remembering; processes active at both encoding and retrieval affect the designation of importance and ultimately, the accessibility of information. For the expert, more elaborate schema allows them to use their prior knowledge to more deeply encode information, and to access the information later with a rich network of cues. For the novice, the processes at encoding are less important. It is the processes at retrieval which influence whether or not information is remembered. The processes do not act independently, there is evidence of an interaction between encoding and retrieval processes. A study is presented which demonstrates the effects of knowledge on remembering product information.

INTRODUCTION

Information that is determined to be important to a theme (Alba and Hutchinson 1987; Anderson and Pichert 1978) or the accomplishment of a goal (Voss, Greene, Post and Penner 1983) is better recalled than information determined to be less important. The assignment of importance or relevance may be made at encoding or at retrieval. Evidence exists supporting both the encoding explanation (Alba, Alexander, Hasher and Caniglia 1981; Ausubel 1963; Ausubel 1968), and the retrieval explanation (Anderson and Pichert 1978; Anderson, Pichert and Shirey 1983; Mandler and Johnson 1977; Pichert and Anderson 1977). Alternatively, research in cognitive psychology emphasizes the interaction between encoding and retrieval as critical in determining what information is recalled (Craik and Lockhart 1972; Tulving 1983; Tulving and Thomson 1973).

The explanation offered in this paper is that some consumers assign importance at encoding, while others assign importance at retrieval. The difference between these consumers is the degree of product knowledge or expertise. The ability to assign importance at encoding requires the consumer to have previous knowledge which will facilitate learning, while the ability to assign importance at retrieval requires an elaborated schema which provides an orderly search for important information. The expert is skilled in distinguishing between important and unimportant information, as well as between relevant and irrelevant information (Alba and Hutchinson 1987). The novice, on the other hand, focuses on surface details (Chi, Feltovich and Glaser 1981), and peripheral cues (Brucks 1985).

The Encoding Hypothesis

The encoding hypothesis posits that processes operative during the encoding of the information ultimately affect what information is learned and remembered. Anderson, Pichert and Shirey (1983) offer three mechanisms responsible for this effect. First, the schema directs the attention of the processor to specific details in the text (see Spilich, Voss, Chiesi and Vesonder 1979). Second, the schema provides a framework or a scaffolding which facilitates the collection of information significant to the schema (Ausubel 1963; Chiesi, Spilich and Voss 1979; Spilich, Voss, Chiesi and Vesonder 1979). Third, the schema equips the processor with rules and applications which allow for elaboration through the generation of inferences (see Alba and Hutchinson 1987).

Support for the encoding hypothesis is offered by Chiesi, Spilich and Voss (1979). They provide evidence that a more developed schema serves as a framework for organizing information as it is encoded. The presence of a framework allows for comprehension of more complex information (experiments three and five). Subjects with more elaborate knowledge structures perform better on tests of recall. The processes active during encoding appear to have had less influence on subjects with less developed schemas.

The Retrieval Hypothesis

The retrieval hypothesis proposes that the schema influences processes responsible for the retrieval of the information. The schema may provide: a guide for an orderly search through memory (Alba and Hutchinson 1987); plausible details for reconstruction if information is missing (Anderson, Pichert and Shirey 1983); and rules for editing less important information (Anderson and Pichert 1978). The more complex the schema directing the search, reconstruction or editing, the more pronounced the effect.

Anderson and Pichert (1978) demonstrate support of the retrieval hypothesis. Subjects given a perspective (either a burglar or a homebuyer) prior to reading a story which describes a home and its contents, were required to recall information from the original perspective and later from the other perspective. The information recalled with the first perspective is interpreted as an indication of encoding effects. The information recalled with the other perspective is interpreted as an indication of retrieval effects. Subjects were found to edit the information they initially acquired since they recalled additional information relevant to the second perspective. The design does not effectively manipulate encoding, and therefore does not test for the effects of the processes active at encoding. Implicit in the paradigms used in the study of either the retrieval or the encoding processes, is the assumption that the processes are independent. Evidence in cognitive psychology suggests that the processes are not independent. The external and cognitive environment at encoding determines the characteristics of the memory trace, which influences the ability to retrieve the original information (Tulving 1983; Tulving and Thomson 1973). The encoding/retrieval paradigm (Thomson and Tulving 1970; Tulving and Osler 1968) requires that both encoding and retrieval be manipulated for the individual processes and the interaction to be understood (Tulving 1983). To properly assess the processes influencing the importance designation, both encoding and retrieval must be manipulated.

In summary, there are three ways that schemas may affect the encoding of information; by directing attention, by providing a scaffolding and by encouraging inferential elaboration. There are also three ways that schemas affect retrieval; by supporting an orderly search, by aiding in the reconstruction of missing information and by providing rules for editing. There is also evidence of an interaction between the encoding and retrieval; encoding specificity for example. Encoding, retrieval and their interaction must be considered when studying recall.

The previous discussion indicates the degree of elaboration of the knowledge structures allows for the processes at either encoding or recall to influence recall. Consumers with different levels of prior knowledge, and therefore different degrees of elaboration in these knowledge structures, will be differentially influenced by the processes active at both encoding and retrieval.

The difference in knowledge structures and their influence on recall, is discussed in the next section.

EXPERTISE

Expert-Novice Differences

The results of a series of studies examining chess experts by Chase and Simon (1973) caused a shift in focus from the differences in search strategies as a source of expertise to the differences in the quantity, content and organization of localized knowledge. Experts are characterized as having more domain specific information (Chi, Glaser and Rees 1982; Mitchell, Dacin and Chi 1993) which is more organized than the domain specific knowledge held by the novice (Alba and Hutchinson 1987; Chi, Feltovich and Glaser 1982; Fiske, Kinder and Larter 1983). Consequently, the expert will have a more comprehensive schema for the domain when compared to the novice.

Lurigio and Carroll (1985) used semistructured interviews, sorting tasks and decision settings to evaluate the structure of expert and novice probation officers' schema and its influence on decision making. They found that expert probation officers integrated new experiences by rejecting less useful information and enriching the present schemas with more useful information. Spilich, Vesonder, Chiesi and Voss (1979) found that high knowledge subjects offered information which was not present in their earlier verbal protocols when later questioned. They attribute this finding to the expert's elaborate schema which facilitates discrimination between more and less useful information. This ability to discriminate facilitates the editing demonstrated by Anderson and Pichert (1978).

H1: Experts will edit (provide information in the second recall which was previously unrecallable) more than will novices, when they are given a second retrieval context.

H2: Experts will edit based on importance, novices will be less able to do so.

Encoding versus Retrieval Processes

Knowledge can be represented as hierarchical, with highly inclusive concepts subsuming more specific information. Availability of the appropriate specific information will improve assimilation of incoming information (Ausubel 1960; Ausubel, Robbins and Blake 1957). This suggests that encoding will be facilitated with a more elaborate knowledge structure which contains more specific information. However, encoding information at a specific level may influence the ability to retrieve the information. For instance, if information is encoded with a general schema (shopping for a bicycle), then all information relevant to shopping for a bicycle will be considered as important. If the information is then retrieved with a specific schema (shopping for a trendy bike or shopping for a durable bike), the retrieved information will differ depending on what is important for a trendy bike in one instance, and what is important for a durable bike in the other. This is editing.

Conversely, if information is encoded with a specific schema which assigns importance on the basis of that schema, and retrieved with a different specific schema, then changing the assignment of importance will be difficult. Thus, less information will be recalled (Cowley 1993). It is the expert that possesses both general and specific schema. The expert will better be able to provide information important to the situation if allowed to encode with a general schema, than if asked to use different specific schema. The novice will always use a general schema to encode information, therefore there will differ less in their performance.

H3: Experts will edit more when information is encoded with a general context and retrieved with a specific context, than if encoded and retrieved with a specific context. There will be less difference in editing performance for novices.

Demonstrating that information can be recovered by providing a different retrieval context is evidence of the influence of the processes active during retrieval (Anderson and Pichert 1978; Anderson, Pichert and Shirey 1983; Pichert and Anderson 1977). A change in the influence of the retrieval condition by changing the encoding condition evidences an interaction between encoding and retrieval.

Summary

The expert will edit more often than the novice. The information edited by the expert will be important to the second retrieval context. Editing provides evidence of the influence of the processes active at retrieval (the retrieval explanation). The evidence is that the designation of importance is made at retrieval.

The expert will edit more if allowed to encode information with a general context, than if provided a specific context. Variation in the magnitude of the influence of the retrieval processes as a result of a manipulation of the encoding condition evidences an interaction between encoding and retrieval.

METHOD

In order to understand the influences of the processes active during encoding and retrieval, two different conditions are used. Retrieval is manipulated in both conditions by providing two different usage contexts on two separate recall occasions. Encoding is manipulated between subjects. In one condition subjects encode with a context, in the other condition they do not. The context condition is a replication of the procedure used in Anderson and Pichert (1978) which manipulates retrieval within subjects. In the no context condition subjects are provided usage contexts at retrieval only.

Subjects and Design

Sixty Six undergraduate students of an eastern university were randomly assigned to one of two encoding conditions: context or no context. [Four of the subjects did not understand the instructions and one subject guessed the hypotheses of the study, their data was not included in the analysis.] Those assigned to the context condition were given a usage context before being instructed to read a story slowly and carefully. Those assigned to the no context condition were not given a usage context, they were just asked to read the story slowly and carefully. Students were allowed to take as much time as they wanted to read the story once. Reading time varied between 1.5 and 3 minutes.

Recall was measured twice. Once for an image related context, and again for a function related context. [The image related context was operationalized by instructing the subjects to imagine that they have recently joined a bicycle club, that the club meets for rides on weekend afternoons. They have been to one meeting, and they like the people in the club very much, but they noticed that everyone has a trendy, stylish bike. They are going shopping for a new bike. The functional usage context is operationalized by instructing the subjects that they want a bicycle to get them from point A to point B. That they do not need anything fancy, just something durable and reliable. They are also concerned for their safety on the street.] Consequently, the design contained two between subject factors; 2 context conditions; context, no context x 2 knowledge levels; expert and novice, and one within subjects factor; image and functional contexts.

Subjects were designated as expert, intermediate or novice on the basis of their subjective and objective knowledge, familiarity and experience scores. Only experts and novices are used in this analysis, this is discussed in the Measure of Expertise section.

Stimulus

Product information was embedded in a story. The story was 340 words and contained 61 idea units. The product information was presented as though it was being seen in a bicycle shop. There were four different types of bicycles mentioned in the story that fall into two general usage contexts; image related and functional. Terminology in the story was not technical, any less familiar terms were explained in nontechnical language. Attributes and benefits were stated, there were no abstracted comments included (ie. the bike is fun to ride). The story was pretested to ensure an equal amount of important information for each context. [Twenty students at an eastern university participated in this pretest. Each student read the story and rated the importance of each idea unit to one or the other of the usage contexts. Each idea unit was rated on a five point scale anchored with not at all important and very important. There were 14 ideas important to the image perspective only and 15 ideas important to the functional context only. There were 9 ideas rated as uniquely important to each perspective, but not as highly. The remaining 14 idea units were irrelevant to either of the two usage contexts. An analysis of importance clusters revealed that the ideas were either uniquely important to a perspective or of little importance. No idea units were important to both perspectives.]

Measures of Expertise

To properly capture all of the dimensions of expertise, four measures were taken; experience, familiarity, subjective knowledge and objective knowledge. The experience measure was a self report measure of how often the subject rides a bicycle as indicated on a ten point scale anchored with never and very often. Familiarity was measured on a ten point scale anchored with novice and expert. The subject was asked to indicate how familiar they felt they were about bicycles. The subjective measure of expertise was taken as an indication of the amount of information the subject held with respect to bicycles on a ten point scale anchored with novice and expert. Finally, objective knowledge was a raw score of multiple choice questions, definitions and the number of accessible brands.

The coefficient alpha for the sum of these four measure was .93. All of the correlation coefficients were significant (p < .0001).

[The raw scores for the four measures of expertise were correlated as follows;

                    Subjective         Objective         Familiarity         Experience

Subjective        1.00

Objective         .76                     1.00

Familiarity        .88                    .77                  1.00

Experience       .78                    .71                  .72                 1.00 ]

The measures were standardized and summed as the criterion for knowledge class. The pretest scores were added to the sample and an adjusted thirds split was performed. [The sample was split such that two subjects with the same score were assigned to the same group.] Of the sixty one subjects in this sample, there were 21, 22 and 18 subjects were designated as novice, middle and expert subjects respectively. [The mean rating subjective expertise for the experts was 5.85 of 10, and 1.45 for the novices, is significantly different (p = .0001).]

Procedure

Subjects were randomly assigned to either the context or no context conditions. Subjects in the context condition were given the image context. All subjects read the stimulus information and spent the next twelve minutes working on a task of logical inference (French, Ekstrom and Price 1963).

At the time of the first recall, subjects in the no context condition were given the image related usage context, while subjects in the context condition were instructed to think back to the original story about the bicycle shop. All subjects were instructed to write down everything they could remember about the story. [If they were told that they could not remember the exact words, but they could remember the meaning, to write down a sentence or part of a sentence that was as close to the original as possible.]

Following the first recall task subjects spent five minutes working at the Surface Development Test (French, Ekstrom and Price 1963) which requires that subjects mentally "fold" a two-dimensional figure to match a three-dimensional representation.

Subjects were then told that people can sometimes remember information that they thought they had forgotten if they were given a new perspective with which to think about the information. They were asked to think back to the original story with the following context in mind, they were then provided with the functional usage context. They were asked to recall all of the information again.

Finally, subjects completed a questionnaire gathering the expertise measures, asked what they believed the experimental hypotheses were, thanked for there participation, debriefed and awarded 1.5 bonus marks in their introductory Commerce course.

Dependent Measures

The recalled statements were compared to the idea units from the story. If the subject included enough information to indicate some memory of the idea, credit was given. However, if any of the information was incorrect, credit was not given. Idea units unrelated to those in the story are not included in this analysis.

There are four dependent variables. The EDITING variable is the number of idea units included in the second recall that were not included in the first recall. The EDITING variable is subdivided into IMPORTANT, RELATED and IRRELEVANT variables. The IMPORTANT variable is the number of edited idea units that are very important to the new context. [A second judge blind to the hypotheses of the study rated 40% of the protocols. 93% of the idea units were identified by both judges.] The RELATED variable is the number of idea units rated as somewhat less important to the new usage context. [As deemed by the pretest.] The IRRELEVANT variable is the number of idea units remembered in the second protocol which are not related to the new usage context.

RESULTS

Replication

Anderson and Pichert (1978) found that when subjects were given a perspective at encoding and then given a new perspective at the time of the second recall, they remembered 7.1% more of the information very important to the new perspective. This translates to approximately one extra idea unit. When the conditions are pooled, subjects participating in this experiment remembered an average of 1.05 idea units very important to the new context (IMPORTANT variable), 0.65 new idea units were related to the new context (RELATED variable), and .46 new idea units were irrelevant to the new context. Consequently, this study replicates the results reported by Anderson and Pichert (1978).

TABLE 1

MEAN NUMBER OF NEW IDEA UNITS BY IMPORTANCE IN THE SECOND RECALL

TABLE 2

MEAN NUMBER OF NEW IDEA UNITS PRESENT IN THE SECOND RECALL, BUT NOT IN THE FIRST RECALL (BY CONDITION)

Hypothesis One

The first hypothesis states that experts edit more than novices. The hypothesis is supported if the expert includes more idea units in the second recall which were not in the first recall than does the novice. The results support the hypothesis, experts provide an average of 3.3 new idea units in the second recall that were not present in the first recall, while novices recall only 1.2 new idea units. This difference is significant (t = 4.5, p <.0001). Hypothesis one is supported, the expert edits more than the novice.

Hypothesis Two

The second hypothesis states that the edited idea units provided by the experts will be important to the second retrieval cue. This hypothesis is supported (see Table One). The expert provides 2.7 idea units which were not included in the first recall protocol. The edited idea units are either very important or related to the second retrieval cue, while the novice provides .9 edited idea units (significantly different from zero, p < .001). The difference in performance between the expert and the novice is significant (t = 3.6, p <.002).

The expert edits based on the importance of the information. This supports the first portion of hypothesis two. However, the novice also edits based on importance. The finding that both novices and experts edit important information demonstrates that the processes active at retrieval influence what is recalled. The designation of importance occurs at retrieval, this is clear because the edited information is important to the second retrieval context, and not to the first retrieval context.

Hypothesis Three

The third hypothesis states that the expert will provide more information important to the new context in the no context condition than in the context condition. This hypothesis is supported as the new important and related information provided by the expert is 1.5 idea units in the context condition and 3.4 in the no context condition, the difference is significant (t = 2.45, p < .01). The difference in performance between the two conditions lies primarily in the information that was very important to the new usage context (t = 2.57, p < .024), not in the information related or somewhat less important to the new context (t = 1.08, p <.29).

There is a difference for the expert between the context condition and the no context conditions, which suggests that the interaction of the processes active at encoding and those active at retrieval is influential in the designation of importance, and what is ultimately recalled. The provision of a context at encoding does not facilitate the influence of the retrieval process (demonstrated by editing), this suggests that an encoding context may interfere with retrieval for the expert.

There is no difference in the editing performance of the novice between encoding and retrieval conditions. This suggests that although the processes active at retrieval are somewhat influential (see hypothesis one), the processes active during encoding do not affect what is recalled.

The interaction of encoding and retrieval processes appear to be influential in learning and remembering for the expert, but not for the novice. This is consistent with the work of Chiesi, Spilich and Voss (1979).

DISCUSSION

The study presented in this paper demonstrates that experts recall different information in different situations and the information edited by experts for a new situation is important to the that context. This supports the retrieval hypothesis. With the data collected in this study it is impossible to determine whether the schema guides the search through memory or conducts the reconstruction of the original information.

The enhanced performance of the expert in the retrieval condition suggests that encoding with a general context and retrieving with a specific context facilitates editing. The provision of a context at encoding does not facilitate the ability to edit at retrieval. The difference in editing between context and no context conditions supports the interaction hypothesis in the case of the expert.

The novice is less able to draw different information from memory in varying situations. An explanation of the inability of the novice to distinguish between the important and the unimportant given a situation could be put forth. Though the usage contexts were straight forward, and the product category is not completely unfamiliar to most students, novices are certainly less able to identify the important aspects of product information when compared to experts. The editing performance of the novice does not vary between conditions. This suggests that the processes active during encoding do not effect the accessibility of information at retrieval. As there is no evidence of the encoding explanation, there can be no evidence of an interaction between encoding and retrieval. Future research might investigate the presence of an interaction when the processes at encoding are active in the establishment of the importance of the information.

Results presented in an earlier paper suggest that experts recall more information when provided with a specific context at encoding (Cowley 1993). However, when editing is considered, it appears that a general context at encoding is more facilitating for the expert.

The contribution of this paper is to demonstrate that experts and novices differ in their ability to edit product information given different usage contexts. Also, that the processes active at both encoding and retrieval are important for the expert.

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