Summary

The paper argues that iterative process is widely accepted to be beneficial to design and designer. The authors extend iteration by brining in parallelism and comparing parallel iterative procedure to serialized iterative procedure. The authors first introduced potential theoretical benefit of parallel design, in which they brought about three hypotheses: Parallel prototyping leads to feedback comparison and produces higher quality designs; Parallel prototyping results in more divergent concepts; Parallel prototyping leads to a greater increase in design task-specific self-efficacy. The main portion of the paper is dedicated to a between-subject experiment where the participants are asked to develop web advertisement as produce of iterative design process. The independent variable is the structure of such process – parallel or serial. In short, parallel ads outperforms serial ads overall. Not only do they attract more user and receive higher ratings, but also demonstrate more diverse than serial ads. Increased self-efficacy from the parallel group is also observed during the experiment. Two follow-up studies are added at the end to: assess potential bias and examine the value of scripted ad critique statements. The paper tries to encourage a wide adoption of parallelized iterative approach.

Reflection

Involved in some sort of creative design myself, I find this paper both scientifically robust and practically impactful. The paper is well written and clearly organized. I can follow the authors pretty easily and without much confusion. The study is focused on the topic/research questions/answer to hypotheses and not trying to cover too much. The authors even have experts developed scripted ad critique statements to ensure equality in the feedback each participant and participant group receive during iterations. As for measurement of performances, measured variables have strong connection to the hypos. The analysis and discussion are all well documented as well. The appendix is informative and increases overall validity of the study.

Iterative design is inevitable. It is not likely that one can come up with a prototype that will meet all requirement perfectly. Based on the feedback, one can make it better. Usually this is serialized process. But this study suggests that providing iterative feedback on more prototypes can lead to a better result as well as building better confidence for the designer. Parallel process might be hard at first for sure, because more prototypes are required in early stages. But with the same amount of iterations, meaning that the total number of prototypes is created anyway, the initial struggle can be paid off.

I do like the two short follow-up studies. One answers a potential bias of the study, which leaves less room for critics on the validity of the work. The second one ensures the pre-scripted critique statements are valuable and reliable enough for the purpose of the study. I hope these two studies are not result of submission rejection J.

Question

I guess my biggest question about the work would be the validity of divergence measurement through crowdsourcing. Given the number of workers and data size, wouldn’t it be too much for such few people?