EXAMPLE 15.10 Right Shade of Green
It is commonly thought that environmentally friendly consumption is driven by a desire to protect the environment and not to enhance one’s self-image. Is that the case in all settings? To study this, a two-factor experiment was run, in which subjects looked at an advertisement for a fuel-efficient vehicle and then reported their purchase intentions. One factor was whether the advertisement had a self-benefit or other-benefit appeal. The other factor was the type of accountability (public or private).8 Here are the mean purchase intentions:
15-12
| Accountability | |||
| Appeal | Public | Private | Mean |
| Self-benefit | 3.26 | 4.58 | 3.92 |
| Other-benefit | 4.84 | 3.37 | 4.11 |
| Mean | 4.05 | 3.98 | 4.01 |
The means are plotted in Figure 15.4. In the analysis of this experiment, only the interaction is statistically significant. How are we to interpret these results?
Figure 15.4: FIGURE 15.4 Plot of average purchase intent by accountability and appeal, Example 15.10.