Product Knowledge As an Explanation For Age-Related Differences in Children's Cognitive Responses to Advertising

Carolyn L. Costley, University of North Carolina
Merrie Brucks, University of North Carolina
ABSTRACT - Past research has fount that children's responses to advertising differ by age. Of the variables associated with age, those which account for these differences have not yet been determined This paper investigates the acquisition of product knowledge as an explanation of age-related differences in children's cognitive processing of advertising Results of an empirical study indicate that product knowledge provides an incomplete explanation of age differences in cognitive response to advertising Knowledge about advertising, strategic knowledge, and developmental maturity are suggested as variables for future research
[ to cite ]:
Carolyn L. Costley and Merrie Brucks (1987) ,"Product Knowledge As an Explanation For Age-Related Differences in Children's Cognitive Responses to Advertising", in NA - Advances in Consumer Research Volume 14, eds. Melanie Wallendorf and Paul Anderson, Provo, UT : Association for Consumer Research, Pages: 288-292.

Advances in Consumer Research Volume 14, 1987      Pages 288-292

PRODUCT KNOWLEDGE AS AN EXPLANATION FOR AGE-RELATED DIFFERENCES IN CHILDREN'S COGNITIVE RESPONSES TO ADVERTISING

Carolyn L. Costley, University of North Carolina

Merrie Brucks, University of North Carolina

ABSTRACT -

Past research has fount that children's responses to advertising differ by age. Of the variables associated with age, those which account for these differences have not yet been determined This paper investigates the acquisition of product knowledge as an explanation of age-related differences in children's cognitive processing of advertising Results of an empirical study indicate that product knowledge provides an incomplete explanation of age differences in cognitive response to advertising Knowledge about advertising, strategic knowledge, and developmental maturity are suggested as variables for future research

INTRODUCTION

Age has surfaced as a major variable in describing individual differences in children's reactions to advertising However, age encompasses many factors that may be the cause of such differences Although it has been shown that older children can process advertising messages better than younger children, it is not clear whether this ability stems from their increased knowledge about the products being advertised or from other elements that change with age, such as developmental maturity This distinction has practical as well as theoretical significance If it can be shown that age differences disappear when product knowledge is equal across age groups, it would indicate that younger children might be able to increase their abilities to process advertising messages by acquiring product experience and knowledge On the other hand, if age differences are due to developmental maturity, little could be done to increase the abilities of younger children

This paper investigates the acquisition of product knowledge as an explanation of age-related differences in children's cognitive processing of advertising A brief description of children's responses to advertising found by consumer researchers is followed by a discussion of some of the relevant research in cognitive psychology Hypotheses derived from this work are presented and tested empirically The paper concludes with a discussion of children's information processing

BACKGROUND

Age-related differences in children's reactions to advertising are a robust finding in consumer research. Research ewidence indicates that older children are better able to distinguish TV advertising from programming (Robertson and Rossiter 1974; Ward, Reale, and Levinson 1972), exhibit a greater degree of skepticism towards advertising (Blatt, Spencer, and Ward 1971; Roberts et al 1980; Robertson and Rossiter 1974; Ward, Wackman, and Wartella 1977), and recall a greater amount of commercial contents (Blatt, Spencer, and Ward 1971; Ward, Reale, and Levinson 1972; Rubin 19?4; Ward, Wackman, and Wartella 1977) than younger children These observed differences have frequently been attributed to cognitive development, most specifically, Piaget's theory of cognitive stages (Rubin 1974; Ward, Wackman and Wartella 1977)

Piaget's theory views progress in children's cognitive skills as a series of four major stages through which children pass as they grow from infancy to adulthood (see Flavell 1963; Piaget 1983; Piaget and Inhelder 1969) Stages are defined by children's capabilities to mediate incoming stimuli These capabilities are believed to result from both experience and maturation

Since this study does not deal with very young children, only the two later stages in Piaget's theory are discussed here These two stages span the ages from 7 to 15 and represent an important group of consumers In the "concrete operational" stage (ages 7 to 10), thought is primarily in terms of concrete objects and the immediate present A child in this state might tell you that an apple fell from a tree because it broke off of its branch A "formal operational" child (age 11 to 15) will be more likely to tell you that gravity caused the apple to fall It is in this later stage that the child's thought becomes guided by abstractions Flavell (1963, p 205) summarizes the basic change in orientation that occurs between these two stages

No longer exclusively preoccupied with the sober business of trying to stabilize and organize just what comes directly to the senses, the adolescent has, through this new orientation, the potentiality of imagining all that might be there - both the very obvious and the very subtle - and thereby of much better insuring the finding of all that is there

Although observed age differences in children's reactions to advertising have often been attributed to Piaget's theory of cognitive development, few if any of these studies used measures of cognitive development other than age Perhaps the observed age differences were due to increases in knowledge of products rather than to the change in orientation from the concrete to the abstract that defines the difference between these developmental stages

Research in cognitive and social psychology has clearly demonstrated the critical role of prior knowledge in information-processing activities (e.g., Chase and Simon 1973; Chi, Glaser, and Rees 1981; Chiesi, Spilich, and Voss 1979; Larkin et al 1980) The accumulation of knowledge is also suggested as a major factor in children's development of information-processing abilities Chi (1981) has argued that progress in cognitive development is due largely to knowledge increases in content areas "Content knowledge" refers to specific knowledge of facts and concepts within a particular content area or domain and knowledge of how to solve problems and accomplish tasks within that domain "Strategic knowledge" refers to knowledge of problem solving procedures which can be applied across specific content areas [The terms content knowledge and strategic knowledge have been used in the literature on children to refer to the concepts termed "declarative knowledge" and "procedural knowledge" (see Anderson 1980).] For example, knowledge that rehearsal is a useful aid for remembering can be applied to any content area.

Chi has explored the distinction between content knowledge and strategic knowledge on memory performance as measured by recall and clustering tasks (Chi 1978; Chi and Ceci 1985; Chi and Koeske 1983) For example, in a case study involving a single child and knowledge about dinosaurs, Chi and Koeske (1983) found memory performance to be a function of greater knowledge about classes of dinosaurs (content knowledge) Since a single individual was studied, general strategic knowledge was exactly the same across performance sets Only the content knowledge varied.

Chi (1978) also found that knowledgeable children could out-perform adults on a recall task Chi compared the performance of children who were knowledgeable about the game of chess to adults who were novices in this domain Both groups were shown a chess board with pieces in a mid-game position, and later were asked to reconstruct the board from memory The children did remarkably better than adults in reconstructing the locations of pieces Lindberg (1980) conducted a similar study using word listings and obtained concurring results These findings suggest that possession of content knowledge can overcome a lack of age-related strategic knowledge Flavell comments (1985, p 115)

Just how much of postinfancy cognitive development can ultimately be accounted for by the acquisition of domain-specific knowledge is currently one of the "hot issues" in the field

The ability to apply product knowledge to a specific advertising situation may depend on the child's knowledge of information-processing strategies i.e., strategic knowledge Roedder (1981) has categorized children into three types based on their knowledge of information-processing strategies These three types are characterized by increasing abilities to focus attention and to use sophisticated storage and retrieval strategies Strategic processors (ages 10/11 and up) spontaneously employ sophisticated storage and retrieval strategies Cued processors (ages 6-9) do not aromatically use effective strategies for processing, but can do so when instructed in useful techniques Limited processors (under 6) cannot use information-storage and retrieval strategies even when prompted to do so However, the ability to use more complex processing may occur later than proposed above When the task involves the allocation of attention to central and incidental material, strategic processing does not occur until 13 years, and cued processing does not occur until 8 years (Roedder 1981) It is important to note, however, that Roedder's work did not consider changes in content knowledge as Part of cognitive growth

In summary, various explanations for data-related differences in children's processing of advertising have been discussed Piaget's theory of cognitive development suggests that children's thought processes progress in stages, which are qualitatively different in problem-solving orientation These developmental changes may be due to increases in content knowledge, strategic knowledge, and/or to physiological maturation Roedder's work reviews age-related differences that are due to differences in strategic knowledge The work of Chi and others indicates that increases in domain-specific content knowledge may be a cause of age-related differences

RESEARCH OBJECTIVES

This paper investigates the role of product knowledge, which is an area of content knowledge, on children's cognitive responses to print advertising Product knowledge has been shown to affect the number and type of cognitive responses in adults (Edell and Mitchell 1978), and thus, is likely to affect cognitive responses in children In young children, however, a lack of strategic knowledge or insufficient cognitive development may preclude the use of product knowledge to generate cognitive responses Thus, in this study, two questions were addressed First, do younger children who possess knowledge about a product class respond differently than unknowledgeable children of the same age to advertisements for that product class? In other words, are younger children able to utilize their product knowledge? Second, do these knowledgeable younger children respond differently than equally knowledgeable older children? In other words, does age provide an information-processing benefit independent of product knowledge?

The cognitive responses of interest in this study are those that involve elaboration, i e , statements that are reactions to, qualifications of, or illustrations of the material in the communication (Cacioppo, Harkins, and Petty 1981) Elaborative responses can be classified as counterarguments, support arguments, and source derogations (Wright 1973) Counterarguments require using prior knowledge to "argue" against implicit and explicit advertising messages Support arguments are thoughts that favor the advertising message, and source derogations are thoughts that are critical of the advertiser or advertisement (Wright 1973)

METHODOLOGY

Children from two age groups with two different levels of product knowledge took part in the study A group of 8 and 9 year old children, representing the concrete operational state of cognitive development, was diwided into two experimental conditions Subjects in Condition 2 received a training session about the product class, designed to increase their knowledge level, while subjects in Condition 1 received a training session on a peripheral issue associated with the product class

A group of 11 and 12 year old children was also obtained, representing the formal operational state of cognitive development This group was also a high knowledge group, and received the same training session as did subjects in Condition 2 Please see the Figure for a summary of the experimental design

FIGURE

EXPERIMENTAL DESIGN

It will be noticed that only three groups have been included, unknowledgeable young children, knowledgeable young children, and knowledgeable old children Unknowledgeable old children were not included because most older children had already acquired knowledge about the product class used for this study

The subjects were asked to think aloud as they looked at a series of print ads Their oral responses were tape recorded, transcribed, and then classified according to the coding scheme described later

Subjects

Subjects were obtained from summer camps in North Carolina To eliminate variations due to gender, only boys were used as subjects All boys in the given age groups participated The camps differed in socioeconomic status and resulted in a heterogeneous sample Within each camp, boys who had just completed the third grade were randomly assigned to either Condition 1 or 2 Boys who had just completed the fifth, sixth, or seventh trade were assigned to Condition 3 All ages fell within the bounds of the cognitive development framework that they were supposed to represent Thirty-eight children successfully completed all aspects of the task 11 in Condition 1, 13 in Condition 2, and 14 in condition 3

Stimulus ads

Print ads were used rather than TV ads because realistic TV ads are difficult and expensive to produce. Age differences in producing cognitive responses to TV ads may be greater than to print ads since younger children may have trouble keeping up with the information flow of TV Because the print medius offers individual control of the rate of information flow, differences between age groups in responses due to "ability to keep up" are eliminated

A hypothetical new brand of BMX bicycle (BMX stands for bicycle moto-cross) served as the subject of the ads. The two ads used in the study included information that was deliberately false or inconsistent In one ad, the headline claimed that the bicycle comes with a fork stander, but the ad did not show one on the large illustration of the bicycle In the other ad, the subheadline stated that one can do "endos" and "rockwalks" (two types of stunts) with the bicycle But the ad pointed out that the bicycle does not have hand brakes which are necessary to perform both the endo and the rockwalk) This ad also claimed a laid-back seat, but pictured a regular straight seat The training sessions of Conditions 2 and 3 emphasized the information necessary to comprehend these contradictions Rough sketches were provided to a graphic artist, who created authentic looking black-and-white advertisements

In order to ensure that the discrepancies were noticeable, several BMX experts, used 12-16, were asked if they noticed anything wrong with the ads All were able to spot the inconsistencies Although outright deceptions are relatively uncommon in advertising today, these ads ensured the-t the subjects had the opportunity to counterargue If children do not counterargue against obvious falsehoods, it is highly unlikely that they would counterargue against more subtle forms of persuasion

Dependent variables

She dependent variables were cognitive responses to the two ads Oral thought listings were used in this study since writing is a chore for young children and might interfere with accurate expression of their thoughts In addition, improvement in oral verbal ability appears to be less dramatic than improvement in --writing ability between these age groups

Responses were first distinguished as to whether they were elaborative or not. Non-elaborative responses include statements that simply repeat message arguments, such as "It says it has a fork stander" Elaborative responses were classified as counterarguments or support arguments and then further classified as relevant or irrelevant. Responses were classified as relevant if they dealt with the attributes or uses discussed in the training sessions The coding of "irrelevant" simply meant that the response did not draw on the knowledge base under investigation Relevant arguments were further classified as accurate or inaccurate However, only one counterargument in this study was classified as inaccurate. Inaccurate support arguments are exemplified by "Neat, it has fork stander," when the bike is pictured without one. One of the authors coded all of the data, blind to the experimental condition of the subject. No estimate of interjudge reliability exists for the data.

Control variables

Involvement with the product class was measured prior to any experimental manipulations This measure was included because it has been suggested that involvement affects the generation of elaborative responses (Batra and Ray 1983; Greenwald and Leavitt 1984; Petty and Cacioppo 1981) The four items were four-point Likert scales and addressed liking for BMX bikes, interest in friends' bikes, interest in information about BMX bikes, and reading of BMX magazines. T-tests between the older group and the two younger groups on the involvement scale indicated that the younger children were significantly more involved with the product class than the older children (p < .06) Because the older children were less involved, this may somewhat counter act the age advantage of older children with respect to elaborations. Thus, involvement was included in the analysis as a covariate

There was also a significant difference between age groups in the total number of responses generated for Ad 2 (p < .05) Because this may simply reflect an age difference in verbosity, a separate measure of verbosity was included as a covariate The measure came from the number of responses to an ad from a different product category (seahorses)

Procedure

A two day procedure was followed at each camp location The boys were told on the first day that this research was being conducted for a possible new magazine for kids their age To examine its effectiveness, they were about to receive instruction on some subjects that might be in such a magazine Next, the children completed scale measuring their involvement with BMX bikes, followed by the training sessions

On the second day, the researchers administered a knowledge test The test consisted of 27 questions of which 15 served as a manipulation check on the training sessions Next, the verbal response procedure was explained to the group of boys at each camp The children were individually shown four ads and their thoughts about each were tape recorded The first ad provided the verbosity measure and was followed by the first of the two bicycle ads A dummy ad fell between the bicycle ads The order of the two bicycle ads was alternated as a control for order effects The boys were allowed as much time as they wanted to complete their responses to each ad All responses were transcribed from the tapes and then coded

RESULTS

Knowledge Manipulation

The manipulation check indicated that the training was successful for the most part Five items were dropped from the scale as suggested by reliability analysis (a, 88) T-tests performed on the modified scale indicated that the rest of the training affected knowledge as intended The trained group of eight and nine year olds performed significantly better (p < .01) than the untrained group Young children in the trained group responded correctly to an average of 8.6 out of a possible 10 questions The untrained group responded correctly to only 3.4 There was no significant difference between the children in Condition 2 and the older children (Condition 3), who averaged 8.9 on this scale This was as intended

Hypothesis tests

Analysis of covariance controlling for verbosity and product involvement was performed for each response type for each ad An alpha level of 10 was used in order to increase the power of tho tests Because of the small sample size, the power of the tests is insufficient (.53) to detect a medium effect size even at the .10 level of alpha The power is adequate (.86) to detect a large effect size, however (Cohen 1911)

Simultaneous t-tests were used for each dependent variable to compare the mean of Condition 2 with the means of Conditions 1 and 3 to determine whether knowledgeable younger children respond more like those children similar in age (Condition 1) or similar in knowledge (Condition 3) For the first ad, knowledge significantly increased the total number of counter arguments and the number of relevant support arguments in the predicted direction among the younger children (i e , Conditions 1 and 2) This indicates the value of product knowledge for generation of these types of responses, even in the absence of increased age (and associated levels of strategic knowledge and cognitive development) Knowledge also resulted in a significantly greater number of inaccurate support arguments in the group, contrary to the direction of the hypothesis

Age was related to the total number of support arguments and to the total number of elaborations among the knowledgeable children (i e , Conditions 2 and 3) It appears that age increases these types of responses independent of product knowledge (which was equivalent between groups) and involvement and verbosity (which were statistically controlled) The remaining dependent variable, number of relevant counterarguments, was not significantly affected by either age or knowledge

For the second ad, knowledge did not significantly affect any of the cognitive response variables among the younger children although all but one of the mean-differences was in the same direction as the first ad. Age was associated with a significantly greater number of elaborations, a greater number of counterarguments, and, more specifically, a greater number of relevant counterarguments These differences were observed while product knowledge, involvement, and verbosity were constant The effect for support arguments, which was significant for the first ad, was in the same direction for the second ad, but not significant at the 10 level Neither knowledge nor age were significantly related to the number of relevant support arguments or the number of inaccurate support arguments The Table summarizes tho results for both ads

TABLE

COMPARISONS OF MEAN FREQUENCIES OF RESPONSE TYPES

DISCUSSION

Product knowledge significantly increased the number of counterarguments and relevant support arguments that concrete operational stage children generated However, there was not a significant difference due to the knowledge manipulation on other cognitive response variables for this ad, nor on any cognitive response variables for the second ad As noted earlier, the small sample size resulted in insufficient power to detect a medium effect size, which might account for the paucity of significant effects Further more, reliability of the coding was not estimated, and may have contributed to the lack of significance

Significant age effects were noted for four of the six dependent variables, but not consistently over both ads This finding clearly indicates, however, that product knowledge cannot explain these age-related differences in cognitive processing (since knowledge was equal in both age groups) While Chi (1978) provided ewidence that content knowledge may be responsible for age-related differences in children's information processing, she only examined the process of recall The elaboration procedure under investigation in this study is probably a more complex process than that for recall Thus, the insufficiency of content knowledge to account for age-related-differences may be due to a lack of strategic knowledge among children in this age group (8-9) These results can be interpreted in terms of Roedder's (1981) framework, which labels children in this age group a cued processors Children in this category have strategic knowledge, but do not use it unless cued It may be that product knowledge may only be activated for use in processing advertising messages by children in this age group when the children are cued, or reminded of the elaboration strategy Future studies on the effects of product knowledge should examine strategic knowledge as well as complexity of the processing tasks.

The question of children's defenses against advertising has focused mainly on the production of counterarguments (Brucks, Goldberg, and Armstrong 1986) However, the surprising finding in this study that knowledge increased the number of inaccurate support arguments suggests their relevance to the issue as well This finding indicates that the strategic knowledge of these children may be at a level of complexity such that they can recall related information, but do not go a step further and use it to evaluate incoming information The children may have recalled that fork standers and other attributes were interesting and important and generated support arguments accordingly

Conclusions and Directions for Future Research

Product knowledge appears to provide an incomplete explanation of age differences in cognitive responses to print advertising Older children who were equivalent in product knowledge to younger children produced significantly more cognitive responses of several types, controlling for verbosity and level of involvement It is suggested that one direction for future research is to determine the relative contributions of (and interactions among) product knowledge, advertising knowledge, strategic knowledge related to the process of generating elaborative responses to persuasive messages, stage of cognitive development, and physiological maturity in explaining age effects

This study did find that increasing product knowledge among 8-9 year old children did significantly increase some types of cognitive responses to the first ad, despite their presumed lack of cognitive development and strategic knowledge Thus, a second direction for future research is to examine the necessary and/or sufficient conditions for children to use product knowledge in generating cognitive responses

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