CS474: Human Computer Interaction - Variable Reward

Activity Goals

The goals of this activity are:

1. To explain the use of variable rewards, with an emphasis on the variability, to maintain human attention and engagement

Supplemental Reading

Feel free to visit these resources for supplemental background reading material.

• A Code of Ethics for the Human-Robot Interaction Profession
• Meppe, J. - Why are instagram, facebook, and twitter so damn addicting?
• Eyal Chapter 4
• Norman Chapter 2

The Activity

Directions

Consider the activity models and answer the questions provided. First reflect on these questions on your own briefly, before discussing and comparing your thoughts with your group. Appoint one member of your group to discuss your findings with the class, and the rest of the group should help that member prepare their response. Answer each question individually from the activity, and compare with your group to prepare for our whole-class discussion. After class, think about the questions in the reflective prompt and respond to those individually in your notebook. Report out on areas of disagreement or items for which you and your group identified alternative approaches. Write down and report out questions you encountered along the way for group discussion.

---

Model 1: Variable Reward

Questions

1. In what ways do social media applications feature variable rewards, both individually and for the community?
2. Why do variable reward systems hold our engagement over predictable models?
3. What are some examples of diminishing returns with variable rewards?

---

Explore Further

These curated resources trace variable reward from the psychology lab to your phone:

• Simply Psychology - Skinner’s Operant Conditioning — a clear written primer on reinforcement schedules; pay particular attention to why variable-ratio schedules produce the highest, most extinction-resistant response rates. That schedule is the pull-to-refresh gesture.
• Nir Eyal - Variable Rewards: Want To Hook Users? Drive Them Crazy — from the author of Hooked (our course text): the three types of variable reward (tribe, hunt, self) with product examples of each.
• Schull, N. D. - Addiction by Design — an anthropologist’s landmark study of machine gambling in Las Vegas; the introduction (readable via the publisher preview) shows the deliberate engineering of “the zone,” the state many social apps now optimize for.
• Tristan Harris - How Technology is Hijacking Your Mind — a former Google design ethicist’s essay framing your phone as a slot machine in your pocket; read the “intermittent variable rewards” section alongside the Skinner primer above.

Submission

I encourage you to submit your answers to the questions (and ask your own questions!) using the Class Activity Questions discussion board. You may also respond to questions or comments made by others, or ask follow-up questions there. Answer any reflective prompt questions in the Reflective Journal section of your OneNote Classroom personal section. You can find the link to the class notebook on the syllabus.