Quantitative measures

• Total percentage time: The total percentage time in this context is understood as the percentage of the total time spent by the participant on a particular step as identified by coding scheme in the design activity. This data is extracted from the coded tran-scripts, which also recorded the time spent at every step of the design activity.

For example, if a student spends 10 mins of the total 90 mins in the ‘form exploration’

step then, it is recorded that the student spent 11.1% of the total time on ‘form explora-tion’. The percentage time for all the steps in the activity was calculated for all 28 ac-tivities (14 students x 2 acac-tivities per student). This parameter is used in this context exactly as in previous studies such as Mullins et al. (1999), Ehrlenspiel & Dylla (1993), and Atman et al. (2005).

• Number of transitions: Research into the design process followed by engineers has shown that engineers do not simply progress step by step through the design process but instead iterate through cycles of proposal, testing, and modification (Atman et al.

2005). From this it is plausible that the design process followed by the design students of this study would also follow an iterative design process through multiple steps.

Therefore, the number of transitions is defined as the change the participant makes from a particular step during the activity to another step.

For example, if a student is exploring forms (‘form exploration’ in the coding scheme) and then decides to refer to the persona document for more information (‘persona’ in the coding scheme) then this change is identified and calculated as one transition. In the same way, all the transitions made by the participants during the course of the ac-tivity – linear as per the coding scheme or otherwise – are calculated manually from the activity’s audio and video transcripts. To answer the study’s research questions, the total number of transitions by participants in a group and the average number of transitions per design activity were considered, along with the standard.

• Number of information units considered from the persona document: The design ac-tivity provided the participants with a persona to design for. The persona document provided various types of information such as general demographics, day in the life, fashion sense, passions, possessions, attitudes, influences during a purchase decision, etc. To answer the research questions, it is of interest to examine the amount of infor-mation the participants considered from the persona document. In order to measure the amount of information considered, the persona document was broken down into 10 categories of information:

1. General demographics 2. Day in the Life, hobbies

3. Keywords describing the persona 4. Motivation to buy car

5. Possessions and passions 6. Fashion sense

7. Influencers/influences in buying decision 8. Personality and self-image

9. Aspirations for product usage and product characteristics 10.Quotes from the persona

Each of these categories was further subdivided into smaller units of information. Af-ter removing repeated units of information, there were a total of 44 and 49 units for the German and Indian personas, respectively.

For example, for the German persona, under the “day in the life, hobbies” category, the persona’s hobbies of scuba diving and hiking were considered to be two separate units of information. Obviously each participant will find certain units more important than the others and extract only those specific units as the basis for their design, in ad-dition to considering certain units of information for general understanding.

For this measure, only those units explicitly mentioned (said aloud or written down by the participant) were considered. Therefore, these scores cannot be directly associated with percentage of time spent in either the persona step or the requirements and speci-fication step. The total and average number of units of information considered by the participants were considered for analysis.

• Number of explicit assumptions made: Despite the detailed persona document, the par-ticipant made certain assumptions to proceed in the activity. Assumptions in the con-text of this study are defined as pieces of information outside of the persona document and design brief which the participant considered to help in design.

For example, the influence of the father in the Indian persona might make the partici-pant assume that the father would be a potential user of the car and therefore look to satisfy the father’s tastes as well. As in the previous measure, here only the assump-tions explicitly mentioned by the participant as seen in the transcripts and notes are considered. Again, the total number of assumptions and average number of assump-tions per participant were considered.

• Number of exploration sketches: Sketching as a way of saving and communicating ideas is attractive to designers (Goldschmidt, 2003). Schön (1983) described design sketches as containing “stable residual traces” of designers’ preferences while being rapid and spontaneous. Therefore, the exploration and concept sketches made by the participants are considered for this study as they communicate the participants’ inten-tions regarding the product being designed. In order to remove any sort of ambiguity regarding the freehand sketches, the participants were asked to annotate their sketches whenever possible. In this study, all the sketches by the students are classified into two categories: exploratory sketches and final concept sketches.

Exploratory sketches are those sketches the participant produced during the course of the activity where different possibilities and options are being explored. The final con-cept sketches were those the participant believed to be their final recommendation of the CI for the particular persona. Sometimes a student provided multiple perspectives of their final concept, resulting in more than one final concept sketch per activity.

The final concept sketch proposed by the student contains details about the material, colour, and finish. The number of exploration sketches and final concept sketches were manually counted from the sketches, annotations, and material submitted by the

participants at the end of the activity. The total number of exploratory and final con-cept sketches by a particular group was considered.