Experimental design

recy

3.4.2 Experimental design

T

recycling intentions and actual behaviour. Actual behaviour was measured in terms duct choice i.e. choice of product with recyclable packaging. The experiment followed a random groups design layout (Shaughnessy et al., 2009). Three groups, each with 30 subjects were created (see Figure 3.3). Each group was designated to only one of the three conditions of the independent variable i.e. guilt, pride and control. By carrying out random group assignment the groups were balanced/averaged in terms of individual differences (such as age, gender, nationality, current recycling behaviour, emotional information management tendencies etc.) which ensured comparability among the groups.

Figure 3.3 Experimental groups and corresponding stimuli

Overall, the conditions requirements for causal inference (Shaughnessy et al., 2009)

were met since the exp

intentions and behaviour covaried with the conditions of the experiment; b) the dependent variables (intentions and behaviour) were measured after exposure to different emotional stimuli; c) alternative explanations were hold constant thorough holding conditions constant and balancing.

Several variables and aspects that were considered potential sources of bias for T

subjects received the same explanations and instructions during the experiment; the experiment took place in similar seminar rooms with identical video-audio aid; the respondents were presented with questionnaires that followed the same structure and measured the same variables; two research assistants were always accompanied the researcher for each data collection session; each individual were presented with the same two choices of chocolate. The aim of these measures was to eliminate cofounding effects (i.e. when the variable of interest and another independent variable covary) which could have damaged the internal validity of the experiment (Shaughnessy et al., 2009). However, it must be specified that the measures of holding conditions constant were limited. For example, no measures of recycling knowledge, attitude towards recycling, perception of social norms or social desirability have been included. Thus the results must be interpreted in the light of these limitations. Alternatively, the factors that could not be hold constant because of constraints related to sample availability, time and funding, were instead

averaged/balanced. The data checking tests conducted after data collection revealed that the groups were balanced in terms of age, gender, country of origin, level of education, emotional information management, current recycling behaviour and type of accommodation ensured that the groups were comparable and that alternative explanations were eliminated.

Figure 3.4 below shows the experimental sequence containing seven steps. These steps are discussed in turn below.

Figure 3.4. Experimental sequence 8. Debriefing and distribution of incentive

7. Product choice

6. Data collection about experienced emotions, recycling intentions and demographic variables

5. Presentation of video

4. Data collection about the EIM variables and current recycling behaviour 3. Questionnaire distribution

2. Obtaining subjects' consent

1. Confirmation of broad research purposes, anonymity and confidentiality

Stimuli

The choice of videos as stimuli was informed both by the research objectives and previous experimental studies in psychology and consumer behaviour which have successfully employed such a method (e.g. Lin et al., 2006; Williams and Aaker, 2002;

Wintona et al., 1995; Lang et al., 1996; see also Gross and Levenson, 1995). For

L A A reference

consistency cannot be adequately explained by any potential difference in the perceived amount of product information obtained through the different

B W

degrees of emotion ²¹ These findings offer support for the assumption that colour videos would be able more likely to arouse the desired emotions (i.e. pride and guilt) than alternative stimuli. Scenarios or vignettes were considered less likely to elicit the same intensity of feelings since they largely lack visual or sound elements. The choice of videos was also supported by the views on the dual system model. This model claims the existence of two systems emotional T al system is more experiential and concretive (i.e., encoding reality in concrete images, metaphors, and narratives), the cognitive system is more logical and abstract (i.e., encoding reality in abstract symbols, words, and numbers; Epstein 2003; Lieberman et al. 2002 cited in Amir and Ariely, 2009:

178).

The stimulus for pride was initially developed in the form of printed adverts (see Appendix 3.4). The literature review highlighted potential difficulties in inducing pride, and thus a printed message was considered the appropriate starting point.

The pre-test of the printed ad was carried out with a small focus-group during a 30 minute session, which was followed by a pre-test with 15 students. These steps

portrayed products such as pen, multi-tool, photo album, key organiser, and electronic dictionary.

software. Each of these videos was pre-tested with 10 students in small groups of 2-3 students. These pre-tests lead to several changes which were included in the final version of the stimuli. For those consumers who were not supposed to receive any emotional stimulus (i.e. the control group), a relaxation video was selected from an internet source. The video displayed images of the ocean and Hawaiian beaches, and

T s confirmed

by a pre-test with six students which showed that the video did induce neither guilt nor pride (see attached CD with final version of the adverts). Alternatively the videos presented to the other two groups elicited medium levels of guilt and pride respectively, which meant that the treatments groups were comparable. The pre-test of the three adverts was carried out in conjunction with the appropriate questionnaire (see detailed discussion about the later in Section 5.5).

Actual behaviour

The product used for the product choice task was chocolate (i.e. step 7 in the Figure

T ²²; this was

observed behaviour as opposed to self-reported behaviour (see discussion in Section 5.2. about laboratory experiments). Two types of chocolate which had the same

from a local supermarket. In the case of both products, the packaging displayed pictures of nuts, information about content, calories, the producer and country of origin. The products were selected so that they had high degree of similarity and so that the brand or nut content would not lead to divergent choices. The products however differed in terms of the type of packaging. One chocolate had a recyclable

the other chocolate was wrapped in a thin non-recyclable packaging. The label was

22A T Danish consumers, personal norms

were a significant predictor of their intentions to choose environmentally friendly packaging in the supermarket. However, the study measured only self-report intentions and did not observe actual choice/behaviour. This highlights the contribution of the present study and the potentially superior approach to examining the choice of environmentally friendly products. Moreover, the influence of marketing communications was not tested in T (1999) research.

attached because initial pre-tests showed that the subjects had difficulties in identifying the recyclable properties of the product. The label was placed on top of

was not present on the other packaging. The products differed as well in terms of the colour of packaging the recyclable packaging was a non-glossy red whereas the non-recyclable packaging was a bright glossy green. In order to control for any possible effects due to different product features such as colour, size of packaging, visual design, the subjects were asked: a) to state the chosen product; b) give 2-4