Understanding Multi-Attribute Purchase Decisions: A Research Study with South Sudanese Families in Boston

My name is Maarten Vrouenraets and I am a masters student at the Delft University of Technology (TU Delft) in The Netherlands. Since 2012 I have been affiliated with the YES!Delft incubator. YES!Delft is Europe’s largest high-tech incubator and enables Bachelor, Master and PhD students from the TU Delft to valorise their technological know-how by starting-up innovative businesses.

Numerous of these start-ups aim to leverage the increasing amount of market opportunities the developing world has to offer, many by bringing innovative products to market in support of local development. Proud examples include a low-cost irrigation solution for small and medium sized farmers called aQysta, an affordable biogas systems for rural and urban households called SimGas, and a low-cost solar kit called SolarWorks!. One of the most challenging tasks for these social entrepreneurs is to design a product that does not only satisfy the requirements of the perfectionistic engineering mind, but also fits the basic needs of the local consumer.

I experienced the challenge of fitting product design to local consumer needs first-hand in 2013 as founding member of the Sundried Kenya Foundation. Sun drying fruit and vegetables in order to allow longer preservation times turned out to be a concept that needed to be customized to the dry living conditions of the local Massaï tribe. The importance assigned to consumer needs in the early start-up stages by prominent literature on business development therefore should not come as a surprise (i.e. Lean Startup method by Eric Ries).

CITE’s three dimensional technology evaluation methodology is a unique approach that helps to bridge exactly this gap between the needs of local consumers in the developing world and the capabilities of suppliers, manufacturers and donor organisations.

This spring, as a part of CITE’s suitability research, I have conducted a study to learn more about the way consumers in developing countries prefer to make their purchase decisions. CITE explores “suitability” to understand if a technology performs the task it is designed to accomplish. By understanding the way these consumers go about making a multi-attribute purchase decision, the fit between CITE’s methodology and real-life decision making preferences of consumers in the developing world can be further improved.

About the Research

Our empirical research involved members from the Boston-based South Sudanese Enrichment for Families (SSEF), a non-profit committed to helping South Sudanese refugees and their families who have resettled in Massachusetts. With great passion, 27 of its members have participated in a three-part research study with the aim to provide insight into South Sudanese consumer preferences.

Participants that volunteered to participate in this study were asked to compare four different decision methods for the purchase of a solar lantern. These decision methods differ from each other in the way consumer preferences and product information are combined in order to select the most suitable product to purchase. Decision methods examined included a weighted additive decision rule (WADD), a lexicographic decision rule  (LEX) and an elimination by aspects decision rule (EBA). Compensatory decision methods (WADD) require the decision maker to take into account all product attributes and to express relative preferences for each of these product attributes. Within this study participants expressed their relative preferences by dividing a 100 points over eight product attributes. Non-compensatory decision methods (LEX/EBA) facilitate the selection of a solar lantern based on part of the product information and require the decision maker to express absolute preferences for each of the product attributes. Participants were asked to express their absolute preferences by rank ordering eight product attributes in order of importance.  

Provisional Insights

Firstly, participants were asked how they would go about making a purchase decision in real life and what decision method they preferred to base their purchase decision upon within the study. In motivation to their reasoning participants mentioned only a limited amount of product attributes as being decisive. Furthermore many participants showed non-compensatory behaviour in their reasoning like “Having a water resistant solar lantern will always help me to have power and anything else shall come after.” It seems many participants select a solar lantern based on a few decisive product attributes without considering all product information available.

Secondly, having three consecutive sessions allowed us to test the consistency with which participants were able to express their preferences. In this study inconsistency is considered an indicator for the amount of random error with which a decision maker expresses his/her preferences. Participants seem to show consistency in expressing their absolute preferences for a limited amount of attributes. However, when participants were asked to express preferences in a relative way and for a larger amount of product attributes the inconsistency increases.          

Thirdly, participants were asked to take home a solar lantern and use it between the second and third session. This allowed us to get insight into the way user experience influences the preferences of a decision maker. The big majority of the participants expressed great satisfaction for the solar lantern used and didn’t want to exchange it for a different solar lantern model. Furthermore, for most participants the user experience didn’t change the product attributes that were considered important.

A first glimpse at the results show us that non-compensatory decision methods that select a solar lantern based on a limited amount of product attributes might better fit the actual preferences of a South Sudanese decision maker. In addition, participants seemed to be relatively consistent in expressing their absolute preferences for a limited amount of product attributes. As a result non-compensatory decision methods like a lexicographic decision rule might provide the means to guide these decision makers with high accuracy based on limited product information. This could strengthen the scalability of an evaluation methodology by reducing its costs, as a smaller amount of product attributes would need to be evaluated to effectively guide a consumer’s purchase decision.

It needs to be noted that these results are provisional and require further validation. The results have been acquired by use of a small dataset of only 27 SSEF members and a single product set of 11 solar lanterns. Further analysis of the results and follow-up research will determine the way in which the research insights can best contribute to the further development of CITE’s methodology.

Working with CITE

During the semester, it has been greatly inspiring to work as part of CITE’s multidisciplinary team. Professors, post-doctoral fellows, and graduate students from a wide range of fields work on a variety of research toward a shared goal.

The integration of CITE’s 3-S approach—studying the suitability, scalability, and sustainability of technologies designed for a developing country context—provides a fantastic new challenge that can only be tackled with great innovativeness and creativity. Furthermore, the developing country context in which CITE’s methodology operates adds to the challenge by being largely unexplored with respect to consumer preferences.

Overall, working with CITE as a visiting student has been a wonderful experience that has taught me a great deal about CITE’s unique methodology. I am very much looking forward to continuing my research aligned with CITE’s challenging mission from back home. 

Wednesday, August 19, 2015
Maarten Vrouenraets
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