This paper describes a usability study of the Nedap voting machine in the Netherlands. On the day of the national elections, 566 voters participated in our study immediately after having cast their real vote. The research focused on the correspondence between voter intents and voting results, distinguishing between usability (correspondence between voter intents and voter input) and machine reliability (correspondence between voter input and machine output). For the sake of comparison, participants also cast their votes using a paper ballot.
The machine reliability appeared to be 100%, indicating that, within our sample, all votes that had been cast were correctly represented in the output of the voting machine. Regarding usability, 1.4% of the participants had cast the wrong vote using the voting machine. This percentage was similar to that of the paper ballot.
Practical implications as well as experiences with this type of usability testing are discussed.
Practitioner’s Take Away
- It is important to conduct user research of voting equipment. The research may focus on a fine-grained analysis of potential user problems or on an overall assessment of the usability of the voting equipment. It will be hard to serve both goals in one and the same study.
- User research can effectively be conducted in the vicinity of polling stations. This makes it easy to design an ecologically valid research context. People also appear to be willing to participate in such a study, provided that it does not take very long.
- It is important to clearly distinguish the test set-up from the real elections that take place in the same building. This can be done by clearly announcing the research with posters, by visually stressing the researchers’ affiliation, and by emphasizing the distinction in the instructions to the participants.
- The best way to be able to include all voting options in the usability study and to be able to verify the correctness of participants’ votes is by using voting assignments. To avoid memory problems, it may be useful to support a voting assignment with a written note.