The Effect of Message Format and Content on Consumers’ Confidence in Their Memory: Another Take on Comparative Advertising

Citation:

Elizabeth Cowley (1998) ,"The Effect of Message Format and Content on Consumers’ Confidence in Their Memory: Another Take on Comparative Advertising", in E - European Advances in Consumer Research Volume 3, eds. Basil G. Englis and Anna Olofsson, Provo, UT : Association for Consumer Research, Pages: 108-113.

European Advances in Consumer Research Volume 3, 1998      Pages 108-113

THE EFFECT OF MESSAGE FORMAT AND CONTENT ON CONSUMERS’ CONFIDENCE IN THEIR MEMORY: ANOTHER TAKE ON COMPARATIVE ADVERTISING

Elizabeth Cowley, University of Western Sydney, Nepean

Consumers are unlikely to use information in a decision if they do not have confidence in their ability to correctly retrieve the information from memory (retrieval confidence). This study investigates how the ad format (direct or indirect comparison, and related or unrelated attributes) affects retrieval confidence. High knowledge consumers have higher retrieval confidence than low knowledge consumers when making recognition judgments, although they are not more accurate. High knowledge consumers are better able to recognise information from indirect comparisons, however their retrieval confidence is higher when the comparison is direct, even when they are wrong. Low knowledge consumers confuse brands more often in direct comparative ads, but their retrieval confidence does not vary.

1.0 INTRODUCTION

The use of comparative advertising has increased over the last 25 years [Approximately 80% of the advertisements in a recent survey of television commercials used a comparative format. The advertisements either compared themselves directly (20%) or indirectly (60%) by comparing themselves to unnamed others (Barry 1993).] (Barry 1993; Iyer 1988; Pechmann and Stewart 1990), although the empirical demonstrations of its effectiveness are mixed. The most obvious advantage of comparative advertising is that the consumer is presumably supplied with more useful information for decision making. Instead of presenting vague or abstract claimsabout the brand and leaving the task of drawing a comparison to the consumer, the comparative format theoretically simplifies the task of evaluating brands by providing the comparison. Assuming, of course, that the information included in the ads is understandable and useful (Barry 1993), and that the consumer remembers the outcome of the comparison.

There are two common instances where a comparative format in an advertising message is used: when positioning or re-positioning a brand in the marketplace, or when trying to convince the consumer that your brand is better than a similar brand. In both cases, it is not only important that the consumer understands how the target brand is similar or better to another brand, but that the consumer is able to remember the information at purchase. It is possible that in the process of trying to educate consumers of the ways in which your brand is different or better, you may serve to remind them of other brands or erode the confidence they have in their ability to retrieve information. Two factors may influence the effective use of comparative advertising. First, whether all consumers are able to detect the fine distinctions made between brands. The more related your brand is to the key benefits or attributes in the market, the more difficult it may be for the consumer to remember any of the specific brands or attributes. Second, whether the consumer is confident in their ability to correctly retrieve the information later (high in retrieval confidence).

1.1 Previous Research of Comparative Advertising

A significant number of research studies have investigated the effectiveness of comparative advertising. Some of the results indicate that ads that employing a comparative format are perceived as more informative (Sujan and Dekleva 1987), more involving (Muehling, Stoltman and Grossbart 1990), more likely to be centrally processed (Drege 1989; Putrevu and Lord 1994), and more persuasive (Levine 1976; Shimp and Dyer 1978; Wilson 1976). Even though comparative ads have been reported to be more offensive (Wilson 1976), less believable (Prasad 1976) and to result in more counterarguing (Belch 1981; Swinyard 1981).

Much of the past research in this area considers the persuasive impact of the comparative format relative to a non-comparative format, surprisingly little research considers the impact of a comparative versus a non-comparative format on memory for the brands (for exceptions see Pechmann and Stewart 1990; 1991). Amongst other issues, Pechmann and Stewart (1990) investigate how the marketshare and format (direct or indirect comparison) affect the memory for the brand. They found that recall was greatest for the lower share brands in a direct comparison. Other researchers have reported that comparative advertisements garner more attention and involvement (Muelhing, Stoltman and Grossbart 1990). In which case one would expect the information presented with this format to be more memorable as well, however, there is some debate about whether the ads are more involving (Gotlieb and Sarel 1991).

Certainly a persistent theme for both practitioners (see Barry 1993 for a review) and consumer researchers (Levine 1976; Pechmann and Ratneshwar 1991; Pechmann and Stewart 1990; Wilkie and Farris 1975) has been the potential for brand confusions when directly comparing two brands in the same commercial message. Sponsor misidentifications are more common when the comparison is direct (Levine 1976; Pechmann and Stewart 1990) and when the ad is not #attention-getting’ because the brands are not market leaders (Pechmann and Stewart 1990; 1991). Little attention has been paid to the type of consumer that is likely to make these errors, or whether the consumer is aware of the potential for confusion and is therefore, is less confident in their ability to retrieve the information correctly.

The importance of confidence in memory has been little studied in the context of consumer research. If the consumer is unsure about their ability to correctly retrieve information from memory, it i unlikely they will use the information in a purchase decision. This intuitively appealing assertion is extrapolated from the results reported by Biehal and Chakravarti (1983; 1986). In the study, subjects were given a choice between brands, some of subjects were presented with brands earlier and in the choice setting (memory and stimulus brands), other subjects were given all brands at choice (all stimulus brands). Those subjects presented with both memory and stimulus brands were either instructed to memorise the memory brands or just choose between them. The results showed that brand choice was strongly affected by the ability to retrieve information about the memory brands. If subjects were instructed to memorise the brands, their choices were the same as the subjects choosing between stimulus brands. If subjects were not instructed to memorise the brands presented earlier, they were likely to choose the brands best remembered, even if they were dominated by other brands. Although confidence measures were not taken in the study, the results are interpreted here to be related to retrieval confidence.

The discussion that follows argues that the relationship between the relatedness of the attributes and retrieval confidence is moderated by the level of knowledge in the product category, and that retrieval confidence is also affected by the format of advertisement. It may be perceived as more difficult to recognise brand information from a directly comparative ad where information about two brands must be processed, than in an indirectly comparative ad where the information provided relates to one brand only. Further, that retrieval confidence may affect recognition judgments. To summarise the model, the format of the advertisement, direct or indirect comparison and related or unrelated attributes, may only influence recognition through retrieval confidence. See the model in Figure 1.

FIGURE 1

THE ROLE OF KNOWLEDGE LEVEL IN THE RELATIONSHIP BETWEEN AD FORMAT AND THE CONFIDENCE IN THE ABILITY TO RETRIEVE INFORMATION (RETRIEVAL CONFIDENCE)

2.0 HYPOTHESIS DEVELOPMENT

2.1 Knowledge levels and Comparative Advertising

The typical comparative strategy assumes that all consumers are capable of making fine distinctions amongst very related brand-attribute claims. The ability to detect and understand differences in attribute levels varies with the amount of knowledge a consumer possesses in a particular product category. For instance, high knowledge individuals have more subclasses of knowledge in a general domain (Mervis and Rosch 1981), and have more knowledge about each subclass (Sujan, Sujan and Bettman 1988), resulting in a more complex structure of information stored in memory. This more complex knowledge structure allows the higher knowledge consumer to better organise information during encoding (Chiesi, Spilich and Voss 1979; Voss, Vesonder and Spilich 1980), and therefore #see’ the relations between brands. A more organised structure for the storage of information facilitates retrieval, and may also increase the confidence in the ability to retrieve information.

Low knowledge consumers, although they may remember the brand names and possibly the attributes, are unlikely to remember which attributes were associated to the brand in question (Cowley 1997). A critical factor in these results is whether the attributes used to differentiate a brand were related to a benefit that other brands also claimed to offer.

2.2 Relatedness of the brands

Research investigating associative network models of memory use recognition to test the effect of increasing the number of the facts associated to a concept, or in marketing terms the attributes to a benefit. A robust finding in these studies is that retrieval of a fact (or an attribute) becomes more difficult as the number of unrelated facts (attributes) learned about a concept (brand) increases (Anderon 1974; 1976; Anderson and Bower 1973; Anderson and Reder 1987; Hayes-Roth 1977; Lewis and Anderson 1976; Reder and Ross 1983; Whitlow, Smith and Medin 1984), and that the effect is attenuated if the facts (or attributes) are related (Reder and Anderson 1980). One explanation for the attenuation is that as individuals accumulate facts that relate to a theme they will be confident enough to use sensibility judgments ("all of the attributes for this brand were related to the ease of use benefit, this one is not, I must not have seen it before" or "all of the attributes for this brand were related to the ease of use benefit, this one is also related to that usage situation, I must have seen it before") instead of retrieving the information from memory. If this explanation is correct, as an individual is more able to use a sensibility judgment in conjunction with retrieval, there will be a marked increase in their confidence in the accuracy of their response. In an advertising context, if the attributes compared in an advertisement are related to the same benefit, then the consumer should have more confidence in their recognition judgement.

On the other hand, if the attributes are unrelated or relate to different benefits, then not only will the attributes be more difficult to retrieve, but the individual must rely on retrieval only in their recognition judgements. In this case, they will have less confidence in their ability to recognise information. An assumption is implicit in these assertions, and that is that the consumer is able to organise the information in order to #see’ the relatedness of the attributes.

2.3 Relatedness and its Relationship to Knowledge Level and Comparative Ads.

For high knowledge individuals who are better able to organise information, the relatedness of facts to the concept should influence recognition. Therefore, high knowledge consumers should have a higher level of retrieval confidence when the attributes are related to the same benefit or usage situation. For low knowledge individuals, who are not likely to organise the information, the relatedness of the facts will not influence recognition. Their retrieval confidence should be the same regardless of the relatedness of the attributes. All of this assuming that the ad is directly comparing one brand to competing brand(s). In the more common indirect advertisement, the consumer is not expected to remember information about two brands, but instead that the target brand is better than unnamed brand(s). Since the amount of information is greater in a directly comparative ad, recognition should be more difficult and retrieval confidence should be reduced.

2.4 Hypotheses

H1: High knowledge consumers will have a higher level of retrieval confidence for recognition judgments than low knowledge consumers.

H2: High knowledge consumers will have more confidence in their ability to recognise brand information when the attributes are all related to the same benefit or usage situation, than when the attributes are related to different benefits or usage situations. The effect will be greater in a directly comparative ad compared to an indirectly comparative ad.

H3: Low knowledge consumers will have the same level of retrieval confidence regardless of the relatedness of the attributes.

3.0 EMPIRICAL WORK

3.1 Design

3.1.1 Study Design

The study is a 2 x 2 x 2 mixed factorial design with one between subject factor and two within subject factors. The between subject factor is level of knowledge (high, low). The within subject factors are #type of message format’ factors: (direct comparative, indirect comparative) and the relatedness of the attributes (related to the same usage situation, related to different usage situations).

3.1.2 Pretesting and Stimulus DesignBat Study

3.1.2.1 The Brands. The brand information was presented to the subjects in the form of print advertisements. The product category is cameras. This product category is interesting to undergraduate students and is complex enough to allow for substantial variation in product knowledge. Hypothetical brand names are used to avoid any effects of familiarity, that might occur with existing brand names. Existing brand names may be more or less familiar to subjects and therefore affect their ability to recall the brands.

The brand names are five letter nonsense words. The names were pretested to check for:

1] associations between the brand names and any existing brand name,

2] associations between the brand names and existing camera brand names, and

3] significant differences in the probability of recalling the different names.

3.1.2.1.1 Pretest OneBSimilarity to Existing Brand Names. Forty undergraduate students were shown twenty brand names with the following instructions:

i] list any characteristics associated with cameras that come to mind when you read each of the hypothetical brands,

ii] rate your familiarity with each of the hypothetical brand names,

iii] state whether the brand name reminds you of other existing brand names and,

iv] identify other similar and related brand names.

Two of the hypothetical names reminded subjects of existing camera brands. Three of the hypothetical brand names (including the two previous names) reminded subjects of brand names for other products. These brand names were not included in the main study. Many of the comments made during the pretest were speculations as to the country of manufacture or the language the word might be taken from. Although there was some consensus as to the country itself, there was no systematic consensus as to the meaning of the #word’ (no more than one subject identified a particular meaning for the word).

3.1.2.1.2 Pretest TwoBMemorability Pretest. Twenty students were shown 16 brand names and asked to rate whether the camera sounded as though it might be #easy to use’ on a scale anchored with #easy to use’ and #difficult to use’. Ten minutes later they were asked to recall as many of the brands as possible. The presentation order was counterbalanced on four lists, as it has been demonstrated to affect the ability of low knowledge consumers to recall brands. When position on the list is a covariate there are no significant differences in the probability of recall between the brands.

3.1.2.2 The Attributes. The attributes are described using simple language. The attributes wereeither related to the same usage situation or they were not. For instance, a direct comparative ad where the attributes were related was composed of the following type attribute claims:

1] Clibo cameras are more useful for portrait photography than Altex cameras because the negatives are larger.

2] Clibo cameras allow for the use of more of the film types required by professionals than Altex cameras.

An example of an direct comparative ad where the attributes were unrelated was composed of the following type of claims:

1] Mileo cameras are better than Fiere cameras for photographing details ... good for technical work.

2] Mileo cameras are tougher and more solid than Fiere cameras ... good for hiking.

3.1.2.3 The Format. The ads were either directly comparative as above, or indirectly comparative as in the following example of an indirect comparative ad where the attributes are related:

1] Renon cameras are the best at automatically controlling for water temperature.

2] Renon cameras have the highest quality underwater flash ... great for scuba diving.

An example of an indirect comparative ad where the attributes were unrelated was composed of the following type of claims:

1] Karic cameras have the widest variety of lens attachments on the market.

2] Karic cameras are the simplest and most basic camera ... good for beginners.

Whether the attributes were related or unrelated to the usage situation was identified by students in a pretest.

3.1.2.3.1 Pretest ThreeBRelatedness of the Attributes. A sample of 20 undergraduate students saw twenty four camera attributes and were asked to rate each attribute as to "How appropriate it would be if you were going to use the camera for ... (travelling/ underwater photography/ professional photography/ amateur photography)?". A twelve cm continuous scale was anchored with #not at all appropriate’ and #very appropriate’. This information is the basis for the preparation of related or unrelated brand-attributes statements.

A second sample of 20 undergraduate students read brand-attribute statements. Examples of the statements are:

"Clibo cameras are compatible with the film types required by professionals."

"Clibo cameras produce large negatives, ideal for portrait photography."

Subjects then used a Likert scale with #strongly agree’ (5) and #strongly disagree’ (-5) at the ends and #don’t know’ (0) in the middle, to indicate whether they agreed with the following statements:

"Clibo brand would be suitable for a professional photographer." (statement one)

"Clibo brand would be suitable for a beginner or an amateur photographer." (statement two)

Subjects also indicated how much they knew about cameras on a ten point scale anchored with #expert’ and #novice’. Pairwise comparisons revealed that there were no differences in agreement between high and low knowledge consumers (brand fan agreement t=-.73, p>.47, related fan agreement t=-.66, p >.51).

Both high and low knowledge subjects indicated agreement when the statements related to the same usage situation, as the statement one does (high=4.6 and low=4.7 of 5). Both high and low knowledge subjects indicated disagreement when the statements did not relate to the usage situation, as the statement two does not (high=-1.95 and low=-2.1 of 5). When presented with unrelated facts, both high and low knowledge subjects indicated that they were not sure whether the brands would be suitable to a usage situation (high=-0.9, low=.02). These mean scores are not significantly different than zero which indicates #don’t know’ (t= -.59, p>.56). These results indicate that the related facts imply a theme or in this case a usage situation, while the unrelated facts do not. The results also reveal that both high and low knowledge subjects are able to infer the usage situation when they see a limited set of the statements simultaneously.

3.1.2.3.2 The Stimulus Sets. Two sets were constructed which contained fourteen ads. Six of the ads were target ads, six were filler ads and two were buffer ads. The ads that were directly comparative in one set were slightly reworded to make them indirectly comparative in the other set.

3.1.2.3.3 Ad Placement. The configuration of the sets were as follows:

buffer, target, filler, target, filler, target, filler, filler, target, filler, target, filler, target, buffer

3.1.3 Test Stimulus

The recognition test included eight of the statements included in the target ads and eight foil statements. There were two types of foil statements: 1] An exaggeration of the claim. If the ad was a direct comparative ad then the exaggeration foil stated that the brands was not better than another brand, but the best on the market, and 2] A brand confusion. If the ad was a direct comparative ad then the brands present in the ad were switched. If the ad was an indirect comparative ad then the brand was replaced with another of the brands seen in the set.

3.1.4 Measures

3.1.4.1 Recognition Response. Memory for the information was measured with a recognition measure. Subjects were asked to indicate whether they saw the statement in the set presented earlier or not. This was a forced choice response, they were asked to answer for all statements by circling #yes’ or #no’.

3.1.4.2 Retrieval Confidence Measure. Subjects were asked to indicate how confident they were in their response to the recognition question. The response was made on a 5 cm continuous scale anchored with #not at all sure’ and #very sure’.

3.1.4.3 Knowledge Measure. Both objective and subjective questions were used to measure expertise and familiarity with the product. The objective measures are designed to test for knowledge of existing brands and attributes. The subjective knowledge measures are designed to test for experience and familiarity with the product.

Objective Measures. Subjects were asked to define technical terms describing the process of taking photos, such as #depth of field’. Subjects were also asked to describe attributes associated to cameras such as #f-stop’. Finally, subjects were asked to list as many brand names for existing cameras as they could.

Subjective Measures. Subjects were asked to rate their familiarity, usage and knowledge on ten poit scales. The anchors for these scales are not very familiar / very familiar, not very often / very often and novice / expert, respectively.

A split median division on the sum of these scores results in 28 high knowledge and 28 low knowledge consumers (the score for two of the subjects lay on the median). The Cronbach alpha for the measure was .72. All of the correlations between the individual objective and subjective measures are significant at p<.001.

3.2 Procedure

Fifty six undergraduate students at a large Australian University participated in the study in exchange for course credit.

Subjects were randomly assigned to one of two stimulus sets. The sets were exactly the same except that the brand names were different and the formats were counterbalanced. Subjects were asked to rate how easy the advertisement is to understand. This task ensured that the subject paid some attention to the ad, but did not demand a high degree of attention.

After reading unrelated material for fifteen minutes, the subjects were required to participate in a recognition test. Subjects were presented with 16 statements about the camera brands. Subjects indicated whether they recognised the statements, and their confidence in the correctness of the response. Three of the participants (all were two low knowledge consumers) did not record their confidence ratings and were not included in the analysis for this reason.

Subjects then completed the knowledge questionnaire, were debriefed and thanked for their participation.

4.0 RESULTS

As expected, the overall recognition performance for high and low knowledge individuals was not significantly different. The results replicate a common finding in recognition studies (Alba 1983; Alba, Alexander, Hasher and Canaglia 1981; Chiesi, Spilich and Voss 1979). An ANOVA of the correct recognitions (hits) indicate that the knowledge level factor does not explain recognition performance (F(1,179)=.01, p>.9).

The results will be reported in two sections: hypothesis testing and other results pertaining to the difference between directly and indirectly comparative ads.

4.1 Hypothesis Testing

The first hypothesis predicted that high knowledge consumers would have more confidence in their responses regardless of whether they were correct or not. A three way ANOVA of retrieval confidence testing knowledge level, whether the statement was studied or not (target or foil), and whether the subject responded positively or negatively, reveals that knowledge level is a significant main effect (F(1, 840)=3.7, p<.053). Cohen’s power statistic for this effect is .90.

As expected in an area where there is little previous research, there were many interesting effects that were not predicted. For instance, whether the statements was seen at study or not was not a significant factor, but whether they were responding #yes’ or #no’ was a significant factor (F=22 , p<.0001 for the low knowledge consumers and F=38, p<.0001 for the high knowledge consumers). Retrieval confidence was significantly higher in positive than in the negative responses. One possible explanation is that when the consumer is very confident in their ability to retrieve the statement, it is used in the recognition judgment. On the other hand, it appears that consumers are not very sure about what statements they have not seen. Since the foils were exaggerations and confusions which are common errors associated with comparative messages, this would not be surprising.

The second hypothesis asserts that high knowledge consumers will have more confidence in their ability to recognis brand information when the attributes are all related to the same benefit or usage situation. An ANOVA of confidence ratings on target ads for high knowledge consumers reveals that whether the attributes are related or not is a significant main effect (F(1, 220)=4.05, p<0.05) where related attribute ads (confidence=34.1) were more confidently recognised than unrelated attribute ads (confidence=30.3).

The second hypothesis also asserts that the effect will be stronger when the advertisement is directly comparative compared to an indirectly comparative ad. This aspect of the hypothesis is not supported. The interaction between the relatedness of the attributes and whether the ad was directly or indirectly comparative is not significant.

The third hypothesis asserts that low knowledge consumers will not vary in their confidence between the related and unrelated conditions. An ANOVA of confidence ratings for low knowledge consumers reveals that the related attribute factor is not a significant factor. This provides support for the hypothesis.

To summarise, high knowledge consumers are more confident in their responses, although they are not more accurate. They are particularly confident when the attributes are related. The low knowledge consumer is as confident when the attributes are related as when they are unrelated. All consumers are more confident when they say #yes’ compared to when they say #no’. There are some interesting results pertaining to the differences in confidence and response accuracy when the format varies between directly comparative and indirectly comparative.

4.2 Directly Comparative versus Indirectly Comparative Advertisements

Whether the ad was directly comparative or indirectly comparative was a significant factor in an ANOVA of recognition response for high knowledge consumers (F(1,440)=6.03, p <.015), but not for low knowledge consumers (F(1, 392)=.01, p>.9). High knowledge consumers were better able to recognise indirectly comparative ads than directly comparative ads. It might be expected, given this result, that the high knowledge consumer will be more confident in their responses for indirectly comparative ads. The results reveal the opposite however, confidence ratings are actually higher for responses for direct comparative ads than indirectly comparative ads. Further, when the ad is directly comparative high knowledge consumers are more confident in saying #no’ when they did see it at study (a false alarm) than when they did not see it at study (a correct rejection). This however, is not the case when the ad is indirectly comparative the confidence ratings are significantly higher when correctly rejecting the ad, instead of when falsely recognising it. Taken together, the high knowledge consumer is more accurate when the ad is indirectly comparative, but is more confident in their ratings when the ad is directly comparative, particularly when they are wrong.

Both high and low knowledge consumers misidentified brands during recognition. The low knowledge consumer was more likely to make this type of errorBparticularly when the foil mixed the brands in a directly comparative ad (probability of false alarm=.81 for low knowledge consumers and .66 for high knowledge consumers). Both high and low knowledge consumers were also likely to falsely recognise the exaggerated claim foils for directly comparative ads. Low knowledge consumers were more likely (probability .82) than high knowledge consumers (.75), but not significantly.

4.3 Limitations and Further Research

One of the limitations of the study is that there were directly comparative ads and indirectly comparative ads, but there were no non-comparative ads included in the study. It would be interesting to compare the results, particularly the confidence in the ability to retrieve ratings (or retrieval confidence ratings), to non-comparative ads. Another limitation of the study is that the tudy phase included only a single exposure to the brand information. Usually consumers are exposed to brand information on multiple occasions. It is likely that the increase in exposures to brand information would influence retrieval confidence.

Clearly, the determinants of retrieval confidence are not well understood. It is important not only to establish what affects retrieval confidence, but also when and to what extent it plays a role in consumer decision making.

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