Effects of 3-D Visualization on Persuasion in Online Shopping Sites: a Moderating Role of Product Knowledge

Kihan Kim, University of Texas at Austin, U.S.A.
Terry Daugherty, University of Texas at Austin, U.S.A.
ABSTRACT - The use of a three-dimensional (3-D) visualization in commercial Websites has been growing. In order to better understand the influences of this technology on marketing, a laboratory experiment (n=104) was conducted to examine the effects of visualization type (3-D vs. 2-D) and prior product knowledge (low vs. high) on persuasion. The results indicate that 3-D visualization positively influences attitude, and this relationship was found to be greater for novices than experts. Furthermore, a consumer’s sense of presence was found to mediate the effects of product visualization type on persuasion as previously postulated. These findings and future implications for developing effecting online marketing strategies are discussed.
[ to cite ]:
Kihan Kim and Terry Daugherty (2005) ,"Effects of 3-D Visualization on Persuasion in Online Shopping Sites: a Moderating Role of Product Knowledge", in AP - Asia Pacific Advances in Consumer Research Volume 6, eds. Yong-Uon Ha and Youjae Yi, Duluth, MN : Association for Consumer Research, Pages: 371-377.

Asia Pacific Advances in Consumer Research Volume 6, 2005      Pages 371-377

EFFECTS OF 3-D VISUALIZATION ON PERSUASION IN ONLINE SHOPPING SITES: A MODERATING ROLE OF PRODUCT KNOWLEDGE

Kihan Kim, University of Texas at Austin, U.S.A.

Terry Daugherty, University of Texas at Austin, U.S.A.

ABSTRACT -

The use of a three-dimensional (3-D) visualization in commercial Websites has been growing. In order to better understand the influences of this technology on marketing, a laboratory experiment (n=104) was conducted to examine the effects of visualization type (3-D vs. 2-D) and prior product knowledge (low vs. high) on persuasion. The results indicate that 3-D visualization positively influences attitude, and this relationship was found to be greater for novices than experts. Furthermore, a consumer’s sense of presence was found to mediate the effects of product visualization type on persuasion as previously postulated. These findings and future implications for developing effecting online marketing strategies are discussed.

INTRODUCTION

The use of a three-dimensional (3-) visualization in commercial Websites has emerged because of the development of computer technology and practitioners’ efforts in presenting interactive virtual product experiences (Gill 2002). Accordingly, a growing number of academic researchers are also exploring the effects of the 3-D product visualization in advertising and marketing (Holbrook 1998; Li, Daugherty and Biocca 2002). In particular, recent work has conceptualized 3-D product visualization as an active user controlled psychological state consumers encounter when interacting with products in computer-mediated environments (Li, Daugherty and Biocca 2001). These compelling experiences are able to initiate psychological states by providing visual and motor sensory feedback enabling consumers to freely rotate, zoom-in or out, and examine an interactive 3-D representation of a product along each axis. Much of this work has found that 3-D visualization conveys an enhanced experience of vividness, clarity, realism, and presence, ultimately increasing the impact of online marketing communications (Holbrook 1998; Li, Daugherty and Biocca 2003).

Although positive relationships between interactive virtual product experiences and marketing effectiveness measures have been found (e.g., Coyle and Thorson 2001; Li et al. 2002; Klein 2003), these results suggest superior 3-D effects over 2-D at any time, which is a presumption calling for additional research. As a result, this study seeks to examine boundary conditions for the positive 3-D effects previously observed by examining individual differences associated with the level of prior knowledge each consumer brings when evaluating a product online. Invariably, the amount of prior knowledge of a specific product, or even category of products (i.e., computers), can influence a consumer’s motivation and/or ability to process information (Petty and Wegener 1999). Ability and motivation variables are especially important in persuasion since they are likely to influence elaboration of product information (Petty and Cacioppo 1986a).

Therefore, the purpose of this study is to extend our knowledge in this area of work by investigating how consumer attitude toward a product evaluated online is impacted by the effects of 3-D product visualization and prior product knowledge. Overall, this research may potentially contribute to the body of persuasion literature in academia, and help practitioners select proper target audiences when developing marketing strategies. Furthermore, clarifying the influence of 3-D product visualization could facilitate a better understanding of online behavior leading to more effective marketing communication strategies. In the proceeding sections, a brief theoretical rational is presented outlining the hypotheses as well as the methodology and results of this study.

THEORETICAL BACKGROUND

Elaboration & Product Knowledge

A significant amount of research in social psychology provides support for the proposition that consumers assimilate information and everyday experiences by engaging cognitive systems (Chaiken 1980; Epstein 1990; Petty and Cacioppo 1986b; Sloman 1996). Within this framework, elaboration has been conceptualized as the amount of thought generated while processing persuasive messages (Petty and Cacioppo 1986; Petty and Wegener 1999). This is because independent factors are more likely to influence cognitive processes when elaboration is not constrained by other variables. In fact, ELM postulates a multiple role for persuasion as an influencing variable as either a peripheral cue or central argument depending on the context (Petty and Wegener 1999). In this regard, central processing necessitates an expenditure of cognitive resources for information scrutiny, while peripheral processing involves more simplistic strategies (Petty and Cacioppo 1981, 1986a).

Among the variables influencing consumers’ information processing styles, ability is one that has been extensively researched in marketing (Petty and Wegener 1999; MacInnis, Moorman and Jaworski 1991; Jaworski and MacInnis 1989). Ability refers to consumers’ skills or proficiencies in interpreting product information in marketing communications (MacInnis et al. 1991). The availability and accessibility of issue-relevant knowledge structures provide the foundation for processing ability. One of the most important variables affecting information-processing ability is the extent to which a person has an organized structure of knowledge (Wyer and Srull 1984). That is, high ability implies that the prior knowledge necessary to interpret issue-relevant information is present and accessible (Alba and Hutchinson 1987; MacInnis et al. 1991). For example, some people are more able to think about issues because of their well-developed product class knowledge (Petty and Wegener 1999). Thus, varying the degree of product knowledge would result in differential processing of a given marketing variable, which in turn, has differential impacts on the subsequent persuasive outcomes. Considering that research is generally consistent with the view that simple cues are more likely to affect susceptibility to influence when prior knowledge is low rather than high (Petty and Cacioppo 1986a), 3-D product visualization, if interpreted as a peripheral cue, may be more likely to influence persuasive outcomes under low rather than high elaboration. Marketing executions can still affect attitude change when information scrutiny is reduced resulting in low elaboration. Such variables operate by either inducing primitive affective states, or because they trigger some simple heuristic cues for making a judgment (Chaiken 1987; Petty and Cacioppo 1986a, 1999).

Presence

One of the most convincing constructs explaining the effects of 3-D product visualization is the psychological process known as presence, or sometimes referred to as telepresence. Steuer (1992) explains this psychosomatic feeling as "the experience of presence in an environment by means of a communication medium" (p.76). When we experience our sense of presence in the physical world, we automatically generate a mental model of this space. In computer-mediated environments, information that stimulates the structure of our experiences are used to activate the same automatic perceptual processes that generate the perception of the physical world (Biocca 1997). Thus, the experience of "being there" is potentially a product of all media (Reeves and Nass 1996), yet interactive multi-sensory environments are able to generate the most compelling sense of presence (Biocca 1997).

Several studies have found that presence is capable of influencing persuasive outcomes based on interactivity as both antecedents (e.g., interactivity and vividness) and consequences (e.g., attitude, behavior intention) (Coyle and Thorson 2001; Klein 2003). Furthermore, Li and colleagues (2002) directly compared 2-D versus 3-D advertising and found that 3-D visualization incorporating interactivity and richness (or vividness) is capable of enhancing subjects’ perceived sense of presence leading to increases in reported product knowledge, brand attitude, and purchase intention.

Hypotheses

Consistent with prior research (e.g., Coyle and Thorson 2001; Li et al. 2002; Klein 2003), positive relationships between product visualization type and persuasion are predicted as follows:

H1: Product visualization type (i.e., 3-D vs. 2-D) will positively influence consumers’ attitude such that 3-D visualization will have a greater influence on consumer attitudes than 2-D representations.

Given that product knowledge is an important variable influencing elaboration, the following interaction effects between visualization (i.e., 2-D vs. 3-D) and product knowledge on persuasion is predicted such that incorporating 3-D visualization is more likely to influence consumers’ attitudinal responses when prior knowledge of the product is low rather than high (Petty and Cacioppo 1986a). Thus, prior knowledge is predicted to moderate the influence of 3-D visualization on subjects’ attitudinal responses. This prediction is consistent with the tradeoff postulate of ELM (e.g., Petty, Cacioppo and Goldman 1981), which suggests that, as one moves along the elaboration continuum, the impact on attitude will vary based on the level of processing influenced by such factors as prior knowledge. That is, at low levels of information scrutiny, relatively low-elaboration judgment strategies (such as going with the early information or relying on heuristics) and low-elaboration judgment mechanisms and processes (such as identification with the source or classical conditioning) have a greater impact on attitudes than they do at high levels of scrutiny. Thus, as the impact of peripheral-route processing on judgments increases, the impact of central-route mechanisms on judgments decreases (Petty and Wegener 1999).

H2: Three-dimensional visualization will have a greater influence on consumer attitudes than 2-D representations when consumers have little prior knowledge of a product. Yet, 3-D visualization will have less effect on consumer attitudes when consumers have more product knowledge.

Finally, consistent with the notion of previous research, the sense of presence should mediate the persuasive effects of 3-D visualization because the interactive nature of 3-D visualization evokes a compelling virtual experience that stimulates the sensation of presence absent from traditional static product representations (Li et al. 2002). Thus, presence is considered a mediator because it is predicted to carries the influence of 3-D visualization to the attitude measures. Note that this role of mediator is different from the role of moderator used in the first hypothesis. Mediation can be said to occur when (1) 3-D visualization affects the presence, (2) the 3-D visualization affects the attitude measures in the absence of the variable presence, (3) the mediator has a significant unique effect on the attitude measure, and (4) the effect of the 3-D visualization on the attitude measure shrinks upon the addition of the variable presence to the model. On the other hand, an interaction is said to occur when the magnitude of the effect of one independent variable on a dependent variable varies as a function of a second independent variable; in such cases, the second independent variable is called moderator.

H3: Presence will mediate the influence of 3-D visualization on attitude.

METHODS

To test the hypotheses, a laboratory experiment was conducted asking participants to access a Website and evaluate a consumer product. A 2 x 2 between-subject factorial design was used with prior product knowledge (low vs. high) and visualization type (3-D vs. 2-D) serving as the independent variables. Subjects were randomly assigned to the visualization type condition with product knowledge assessed beforehand to classify respondents accordingly.

Sample

A total of 104 students were recruited from introductory communication courses at a major southwestern university to participate in the study. In return for their participation, respondents received course credit with informed consent obtained prior to the experiment.

Stimulus Material

After considering a variety of products, a Portable Digital Assistant (PDA) was chosen as the experimental product used in creating the stimuli. In particular, the Compaq iPaq was used as it was found to have adequate variations in reported product class knowledge from a pretest. Two versions of an online shopping WebsiteBeither incorporating 3-D visualization or 2-D graphicsBwere constructed for use as the stimulus material in the experiment (see Appendix). In addition to the basic function of point and click, the 3-D visualization Website incorporates such features as product rotation, movement, and zooming in/out via the mouse. Accordingly, the 2-D version only allowed standard point and click functionality as product visuals were static. Except for the type of the product visualization (2-D vs. 3-D), all other information was identical across the two conditions.

Product knowledge was measured using a five-item seven-point subjective knowledge scale (Mitchell and Dacin 1996). Specifically, respondents were asked to indicate their level of familiarity, understanding of the product characteristics, level of knowledge, knowledge relative the general population, and interest in portable computer devices. The index scores was then obtained by averaging all five items (a=.87) and the conventional median split method was used to divide the sample into high and low levels of product knowledge.

TABLE 1

MEANS AND STANDARD DEVIATIONS OF VARIABLES

Measures

Three variables of primary interest were measured: 1) brand attitude, 2) sense of presence, and 3) product involvement. Brand attitude was adopted from Batra, Rajeev and Ray’s (1986) six-item seven point semantic differential scale (pleasant/unpleasant, useful/useless, cold/warm, poorly made/well made, friendly/unfriendly, and best/worst). Scores of all six items were averaged to derive an index score of brand attitude (a=.91 for post-brand attitude).

Presence was measured by using a sixteen-item five-point scale (strongly disagree/strongly agree) modified from the Independent Television Commission Sense of Presence Inventory developed by Lessiter, Freeman, Keogh, and Davidoff (2001). The items used primarily focus on the traditional definition of "being there" in the mediated environment. A composite score was created to represent an index of presence (a=.79).

Product involvement was measured using a four-item seven-point scale (boring/interesting, unexciting/exciting, appealing/unappealing, involving/uninvolving) adapted from the personal involvement inventory (Zaichkowsky 1985; 1994). The index score of product involvement was obtained by averaging all four items (a=.89) and used as covariate in the ensuing analysis.

Procedure

Upon arrival, each subject completed a written consent form and was given online instructions. Respondents were first asked to answer the following questions before being exposed to the test Website: prior attitude toward the brand, product involvement, and perceived product class knowledge. Then, each subject in the study was directed to either a 2-D or 3-D version of an online shopping Website, and asked to evaluate the product. After being exposed to the test Website, subjects were asked to complete a questionnaire containing the dependent variables.

FINDINGS

Analyses of variance (ANOVA) was used to examine the relationship between product visualization type (3-D vs. 2-D), prior product knowledge, and persuasion. In addition, the mediating role of consumers’ sense of presence was examined.

Descriptive Statistics

Out of 104 participants, 41 (39 percent) were male and 63 (61 percent) were female. Each of the four experimental conditions consisted of 26 subjects. Table 1 shows descriptive statistics, reporting the means and standard deviations of each variable.

Hypothesis Test

All hypotheses were tested with involvement as a covariate, which prevents any confounding effects resulting from subjects’ variation in motivational factors rather than from the primary independent variables of this study.

Hypothesis 1 predicted positive effects for the use of three-dimensional visualization on persuasion. As shown in Table 2, the effects of product visualization type (2-D vs. 3-D) on subject’s attitude change scores showed a significant main effect (F(1.99)=6.16, p<.05), in support of the hypothesis. Specifically, attitude change scores were higher for subjects in the 3-D condition (M=0.79) compared to the 2-D condition (M=0.38). While a main effect for involvement was also detected, this is not surprising considering prior research has identified such a relationship (Li et al. 2001). The key issue is that when involvement was controlled for significant findings were detected for the hypothesized factors.

Hypothesis 2 predicted an interaction effect between the product visualization type and product knowledge on subjects’ attitude change scores, such that 3-D visualization will have a greater influence on consumer attitudes than 2-D representations when consumers have little prior knowledge of a product. Yet, 3-D visualization will have less effect on consumer attitudes when consumers have more product knowledge.

This hypothesis tests the moderating role of product knowledge. As shown in Table 2, a significant interaction effect between the product visualization type and knowledge was found (F(1,99)=16.85, p<.01). Figure 1 shows the pattern of this interaction reporting the means of brand attitude change scores for each condition. The results indicate that, as product knowledge increased, the effects of the 3-D visualization format on attitude change scores decreased. This finding confirms the notion that the effect of product visualization type on persuasion is also influenced by a consumer’s product knowledge, supporting the hypothesis.

Hypothesis 3 predicted that consumers’ perceived sense of presence would mediate the effects of product visualization on attitude change scores. Specifically, this hypothesis tests whether sense of presence carries the influence of the information format to attitude. Table 3 shows the following four results supporting the hypothesis (e.g., Baron and Kenny 1986; Holbrook and Batra 1987): 1) The product visualization format significantly affects presence (b=.25, t(1)=4.61, p<.01); 2) The product visualization format significantly affects the attitude change scores in the absence of presence (b=.20, t(1)=2.18, p<.05), 3) Presence has a significant unique effect on the attitude change scores (b=.58, t(1)=3.99, p<.01); and 4) The effect of the product visualization format on the attitude change scores shrinks upon the addition of presence to the model (b=.20.07; t(1)=2.18.07; p<.05n.s.). An additional Sobel test (MacKinnon and Dwyer 1993; MacKinnon, Warsi and Dwyer 1995) was conducted to examine the statistical significance of the mediation effects, which approached the significance level (z=2.08, p<.05).

TABLE 2

EFFECTS OF PRODUCT VISUALIZATION TYPE AND KNOWLEDGE ON ATTITUDE CHANGE

TABLE 3

MEDIATING EFFECT OF PRESENCE

DISCUSSION

Marketers constantly face the challenge of creating visual displays that expose respondents to marketing-related stimuli in order to capture the essence of relevant consumption experiences. Historically, these methods have generally been confined entirely to the flat two-dimensional surfaces of the printed page or the computer monitor. Recently however, progress has been made toward overcoming this limitation by introducing the third dimension of vision for purposes of visualizing information in marketing communications (Holbrook 1998).

Nevertheless, marketers and Web practitioners’ passion for making fancy Websites that incorporate the most recent technologies has lead to careless uses of 3-D visualization hoping for positive results. Although several prior studies indicate positive relationships between the use of 3-D visualization and persuasion, the question "Do we always have this positive effect?" has remained unanswered. The result of this study suggests that the answer is "It depends," and further indicates the ways that marketers can maximize the positive effects of 3-D visualization.

Consistent with the prior research, the results of this study suggest that Websites incorporating 3-D visualization have greater influences on persuasion compared to the 2-D Websites. However, consumers’ product knowledge was found to moderate the relationships between the product visualization format and persuasion, such that novices (i.e., low knowledge consumers) were more likely to be influenced by the use of 3-D visualization than were experts (i.e., high knowledge consumers). Furthermore, the effects of a 3-D visualization on consumers’ perceptions of a given product were found to be the function of consumers’ sense of presence. In other words, consumers’ sense of presence carried the 3-D information to the persuasive outcome.

In a practical sense, these results provide marketing practitioners with useful information that complements the decision-processing involved in selecting proper target groups and in developing strategies for creating tailored online shopping Websites. For example, when a new product is launched in the market, marketers should use various Web techniques including 3-D features because consumers are likely to have a low level of knowledge about the new product, and the 3-D format can serve as a peripheral cue positively influencing novices’ perception of the product. On the other hand, for some products with inherent involvement, the use of 3-D format might not have any positive effects, or even a negative effect can be found because experts with high motivation to process information are less likely to be influenced by 3-D features, and even unintended negative effects can occur. In academia, the results of this study aid the body of literature on persuasion and information-processing by applying traditional theory (i.e., ELM) to the online shopping context. By taking a theory-driven approach, this study leads to a better understanding of the role of the 3-D visualization on persuasion.

FIGURE 1

INTERACTION BETWEEN VISUALIZATION AND KNOWLEDGE

Although this study contributes to the managerial and academic fields of marketing, it is not without limitations. First, the use of a student sample restricts the external validity. Second, by testing the 3-D effects within a single product (i.e., a PDA), the results should not be generalized across all product categories.

Future research should extend this study in several areas. First, the role of product visualization might play a different function under alternative situations, as suggested by the multiple-role postulate of the ELM (cf. Petty and Wegener 1999). Thus, future research should examine the conditions under which the 3-D format can serve as an argumentation influencing consumers under high and low elaboration conditions. Second, consumers’ affective responses toward the Web experience can be incorporated into the study. This approach could help understanding why consumers’ sense of presence mediated the effects of 3-D format on persuasion. Finally, in addition to investigating the role of subjective knowledge, as in the present study, objective knowledge measure can be incorporated into this study. It would be useful to investigate the relative impacts of subjective and objective knowledge because both types of knowledge are related to aspects of information search and decision-making behavior in different ways (Brucks 1985).

APPENDIX

STIMULUS WEBSITE

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