0. Human beings viewed as behaving systems are quite simple
Human beings viewed as behaving systems are quite simple. The apparent complexity of our behavior over time is largely a reflection of the complexity of the environment in which we find ourselves.
Herbert Simon (1996)
Social Psychology and Decision Sciences Retreat 2016: Introduction, Framework, Topics
Wolfgang Gaissmaier, PhD
Department of Psychology
Social Psychology and Decision Sciences

1. Aspects of Decisions I Which decision was made? → Outcome
How good was the decision?
→ Outcome evaluation
How was the decision made?
→ Process
How good was the decision process?
→ Process evaluation
SPDS Retreat 2016: Introduction, Framework, Topics

2. Aspects of Decisions II
Who made the decisions?
→ Individual differences:
Skills
Expertise
Attitudes
Personality traits
In which situation was the decision made?
→ Structure of the environment / context
Degree of uncertainty
Statistical regularities
Problem representation
Social context
Other context factors (e.g., time pressure, cognitive load, stress)
SPDS Retreat 2016: Introduction, Framework, Topics

3. Ecological Rationality
Mind
Environment
Gigerenzer & Gaissmaier (2011). Annual Review of Psychology
SPDS Retreat 2016: Introduction, Framework, Topics

4. The Science of Decision Making
Descriptive perspective: How do people make decisions? Normative perspective: How should people make decisions given a particular environment? Applied perspective: How can we use basic research to help people make better decisions?
Gigerenzer & Gaissmaier (2011). Annual Review of Psychology
SPDS Retreat 2016: Introduction, Framework, Topics

5. Cluster: Collective Behavior
Topics
Decision Strategies
Risk Perception
Risk Communication
Risky Choice
Outreach
Cluster: Collective Behavior
SPDS Retreat 2016: Introduction, Framework, Topics

6. Decision strategies: The past
Simple decision strategies can yield surprisingly accurate decisions / forecasts
Gaissmaier & Marewski (2011). Judgment and Decision Making
Gaissmaier & Neth (2016). Controller Magazin
Marewski, Gaissmaier, & Gigerenzer (2010). Cognitive Processing
Wegwarth, Gaissmaier, & Gigerenzer (2009). Medical Education
Models of heuristics can capture decision processes well
Bröder & Gaissmaier (2007). Psychonomic Bulletin and Review
Marewski, Gaissmaier, et al. (2010). Psychonomic Bulletin and Review
Groups can make adaptive decisions and improve accuracy, depending on group structure and task environment
Hautz, Kämmer, Schauber, Spies, & Gaissmaier (2015). JAMA
Kämmer, Gaissmaier, & Czienskowski (2013). Judgment and Decision Making
Kämmer, Gaissmaier, Reimer, & Schermuly (2014). Cognitive Science
SPDS Retreat 2016: Introduction, Framework, Topics

7. Decision strategies: The current I
Can fast-and-frugal trees yield accurate real world decisions?
Predicting treatment success in forensic psychiatry
Predicting perceived pain
with Hans Neth, Nathaniel Phillips, et al.
Can cue fluency be an ecologically rational way to order/weight cues?
Focus mostly on the normative question of whether such an ordering/weighting can be competitive
Whether it also describes what people are doing is also investigated as a minor issue (because there already exists ample research on that)
with Tamara Gomilsek, Hans Neth, Lael Schooler, Julian Marewski
SPDS Retreat 2016: Introduction, Framework, Topics

8. Decision strategies: The current II
Does justification foster the use of linear rules instead of exemplars?
Linear rules should be easier to verbalize than exemplar models
Thus, justification could foster linear rules and hinder exemplar models
with Janina Hoffmann, Bettina von Helversen
Do aesthetic judgments by experts differ from novices under time pressure?
Aesthetic visual judgments by novices often depend on simple properties such as symmetry
Experts often prefer less symmetric, more complex arrays
Is this a deliberate choice against what „common people“ like?
If so, the difference between experts and novices could disappear under time pressure
with Ubai Stanicki, Hans Neth
SPDS Retreat 2016: Introduction, Framework, Topics

9. Decision strategies: The future
Doctoral projects (Tamara Gomilsek)
Does forgetting aid decision making?
With Janina Hoffmann => Tamara’s talk
Doctoral projects (Nathalie Popovic)
Does stress reduce adaptive decision making?
With Jens Pruessner => Nathalie’s talk
Doctoral projects (?)
Diagnostic decision making
Following up on diagnostic decision making in groups
Can the take-the-first heuristic work for experts (but not novices)?
With Martin Fischer, Juliane Kämmer
SPDS Retreat 2016: Introduction, Framework, Topics

10. Risk perception: The past
People fear the wrong things: Flying ↑, Disease progression of MS↓, cardiovascular disease↓ Gaissmaier & Gigerenzer (2012). Psychological Science Heesen, Gaissmaier, et al (2013). PLoS One Oertelt-Prigione, Seeland, Kendel, Rücke, Flöel, Gaissmaier, et al (2015). BMC Medicine
They overestimate the benefits of medical treatments Heesen, Kleiter, Nguyen, Schäffler, Kasper, Köpke, & Gaissmaier (2010). Multiple Sclerosis
Kendel, Helbig, Neumann, Herden, Stephan, Schrader, & Gaissmaier (2016). International Journal of Cancer
Social amplification of perceived risks in diffusion chains
Moussaïd, Brighton, & Gaissmaier (2015). PNAS
A sampling framework for risk and uncertainty
Galesic, Kause, & Gaissmaier (2016). Topics in Cognitive sciences
SPDS Retreat 2016: Introduction, Framework, Topics

11. Risk perception: The current
Hidden costs of train strikes on traffic accidents
Does an environmental change (here: train strike) increase other risks (here: traffic accidents)?
with Felix Gaisbauer, Hans Neth, Florian Ermark, Gerd Gigerenzer
Social amplification (or attenuation) of risk in other domains (bicycle helmets, influenza vaccination)
Do prior attitudes predict which information will be passed on?
Does the composition of the group (here: homophily) predict when amplification/attenuation occurs?
with Hans Neth, Helge Giese
A social network perspective on risk perception
Do friends share risk perceptions?
Are risk perceptions contagious?
with Helge Giese
SPDS Retreat 2016: Introduction, Framework, Topics

12. Risk perception: The future
Doctoral projects (Nathalie Popovic)
Does stress amplify the social amplification of risk further?
With Jens Pruessner, => Nathalie‘s talk
BA/MA theses to pilot materials and/or study stress manipulations
SPDS Retreat 2016: Introduction, Framework, Topics

13. Risk communication: The past
Statistical information is misunderstood and/or ignored
Gigerenzer, Gaissmaier, et al (2007). Psychological Science in the Public Interest
Arkes & Gaissmaier (2012). Psychological Science
Phyisicians can be manipulated by the representation of clinical evidence
Wegwarth, Schwartz, Woloshin, Gaissmaier, & Gigerenzer (2012). Annals of Internal Medicine
Wegwarth, Gaissmaier, & Gigerenzer (2010). Medical Decision Making
Even when they have all the relevant information available, they often fail to communicate it clearly
Gaissmaier, Anderson, & Schulkin (2014). Medical Decision Making
Transparent representations help to foster insight
Gaissmaier et al. (2012). Health Psychology
Trevena, Zikmund-Fisher, Edwards, Gaissmaier, et al. (2013). BMC Medical Informatics and Decision Making
SPDS Retreat 2016: Introduction, Framework, Topics

14. Risk communication: The current I
Do physicians know the pros and cons of PSA testing?
Purely descriptive
with Gerd Gigerenzer, Ralph Hertwig, Odette Wegwarth, et al.
What to patients and physicians know about the risks and benefits of treatment options? What is patients’ risk literacy?
with Christoph Heesen et al.
A cross-sectional assessment of risk literacy in medical students
Mostly descriptive
Can we identify elements (e.g., courses) that improve risk literacy?
with Martin Fischer
SPDS Retreat 2016: Introduction, Framework, Topics

15. Risk communication: The current II
Do people who prefer graphs to numbers also understand them?
Choice as a solution to decide how to get which representation (environment) to which individual (mind) (note: is not a solution)
with Rocio Garcia-Retamero
Which graphical representation fosters Bayesian reasoning and why?
Gain insight into actual reasoning processes
Which graphical representations fit best?
with Michelle McDowell, Anna Mayr
Developing a framework for understanding graph processing
Developing a process model of graph processing
How can graphs thus be designed to optimize understanding?
with Michelle McDowell, Mirta Galesic, Yasmina Okan
SPDS Retreat 2016: Introduction, Framework, Topics

16. Risk communication: The current III
Simple tools to facilitate the understanding of cancer screening
Test risk representations and their interaction with numeracy
with Gerd Gigerenzer, Odette Wegwarth
Tools for individualized risk communication (e.g., genetic predictions)
with Rita Schmutzler
Social vs. factual information to change pro-environmental behavior
with Astrid Kause, Mirta Galesic
Frame choices reveal and influence ecological Beliefs
Framing effects of uncertainty
with Astrid Kause, Tarlise Townsend
SPDS Retreat 2016: Introduction, Framework, Topics

17. Risk communication: The current IV
Perceiving sequential percentage changes
with Ruchira Suresh, Hans Neth; => Ruchira’s talk
Ratio bias vs. proportion dominance: Understanding opposing phenomena
with Hans Neth
SPDS Retreat 2016: Introduction, Framework, Topics

18. Risk communication: The future I
BA/MA theses
Can incremental graphs improve risk understanding?
2-group graph (treatment vs. placebo) vs. incremental graph
Equivalent in terms of information
Conceptually, 2-group graphs seem to be more intuitive
Yet incremental graphs reduce information
Can they ever be helpful, for instance, with many options?
Can graphical representations reduce biases in updating risk estimates?
People update risk estimates selectively: good news have more impact on updating than bad news
Could graphical representations reduce this bias?
SPDS Retreat 2016: Introduction, Framework, Topics

19. Risk communication: The future II
BA/MA theses
Can we develop graphical representations that foster or hinder the ratio bias (or, reversely, proportion dominance)?
Some graphs should foster going with the ratio (avoiding the ratio bias)
Other graphs should foster going with n (avoiding proportion dominance)
Can graphical representations reduce the social amplification of risk?
In the communication chain paradigm, people pass on information that fits to their prior beliefs
Can we increase the likelihood that more neutral statistical information is passed on?
SPDS Retreat 2016: Introduction, Framework, Topics

20. Risky choice: The past
Misperception of randomness as a flipside of adaptive (and cognitively demanding) pattern search
Gaissmaier & Schooler (2008). Cognition
Gaissmaier, Schooler, & Rieskamp (2006). Journal of Experimental Psychology: Learning, Memory, and Cognition
This could be adaptive in a largely nonrandom environment, but could be pathological in the extreme (here: in gamblers)
Gaissmaier, Wilke, Scheibehenne, McCanney, & Barrett (2016). Journal of Gambling Studies
Wilke, Scheibehenne, Gaissmaier, McCanney, & Barrett (2014). Evolution and Human Behavior
SPDS Retreat 2016: Introduction, Framework, Topics

21. Risky choice: The current I
Peeks and keeps: Optional risk reinforcement learning
Studying exploration and exploitation
how do people use optional risk to their advantage, or disadvantage, in different environments?
With Nathaniel Phillips, Hans Neth, et al.
Group foraging / collective probability learning
Are groups better or worse with regard to the misperception of randomness and/or the detection of patterns?
How does this depend on the social and incentive structure?
How does it depend on whether patterns are deterministic (and thus demonstrable) or probabilistic (not demonstrable)?
With Hans Neth, Christin Schulz, Ben Newell
SPDS Retreat 2016: Introduction, Framework, Topics

22. Risky choice: The current II
The affect gap in decisions for self versus for others
The affect gap also exists in decisions for others
There may be more defensive decision making in decisions for others (here: Minimax instead of EV)
With Nathalie Popovic, Thorsten Pachur
Choices between gambles in groups
Is there a risky shift in groups?
Do groups go more by EV?
With Juliane Kämmer, Christin Schulz, Thorsten Pachur
SPDS Retreat 2016: Introduction, Framework, Topics

23. Risky choice: The future
Doctoral projects (Nathalie Popovic)
Does stress alter decisions from experience and/or decisions from description?
With Jens Pruessner, => Nathalie‘s talk
BA/MA theses to pilot materials and/or study stress manipulations
SPDS Retreat 2016: Introduction, Framework, Topics

24. Outreach: Teaching decision making
Heuristic decision making and intuition
The adaptive toolbox of decision strategies (including statistical thinking and heuristics)
The importance of the environment: risk vs. uncertainty
The power of simplicity and of ignoring information
Who can rely on intuition and in which situations?
What are organizational obstacles that prevent harvesting intuition?
Defensive decision making
An organizational culture of trust
Companies, organizations, banks
The need to develop interactive teaching materials to train the use of heuristics and intuition, and to harvest participants‘ own experiences
SPDS Retreat 2016: Introduction, Framework, Topics

25. Outreach: Teaching decision making
Risk perception and communication
Risk illiteracy as a collective problem
Lack of evidence culture
A fundamental misperception of randomness fuels superstitions
Social processes can amplify risk perceptions
Insight through transparent representations
Physicians, patient organizations, health organizations, pharmaceutical industry, science journalists
The need to develop interactive teaching materials for a broader range of topics and audiences
SPDS Retreat 2016: Introduction, Framework, Topics

26. Cluster: Collective Behavior
Collective Behavior refers to group-level patterns that emerge from interactions between individual organisms (humans and animals).
Developing a quantitative understanding of, and in some cases controlling, collective behavior is essential for advancing scientific knowledge and practical application.
We will analyze
the complex dependencies among individuals,
the multi-scale collective patterns that emerge from interactions and
the recursive feedback between higher-order collective properties and individual behavior.
We will therefore develop
research designs and experimental protocols,
data collection tools (technical as well as methodical) and
analytic approaches to explore and test mechanisms that explain collective behaviour.
SPDS Retreat 2016: Introduction, Framework, Topics

27. Cluster: Collective Behavior
Which of our projects fit?
A social network approach to risk perception
The social amplification of risk
Group decision making
Risky choice (bandits, lotteries)
Diagnostic decision making
Decision making and risk perception under stress
SPDS Retreat 2016: Introduction, Framework, Topics

28. Cluster: Collective Behavior
Which overarching questions would be interesting? Some individual biases may turn out to be amplified in the collective or, more generally, lead to undesirable collective patterns; other biases, however, may actually turn out to be either alleviated by the collective or even lead to desirable collective patterns. When does which of the two happen?
SPDS Retreat 2016: Introduction, Framework, Topics

29. Cluster: Collective Behavior
To understand these collective dynamics, we would therefore need to
identify interesting phenomena in the literature of individual decision making and cognition,
develop formal models of the underlying processes (or harvest them where they already exist),
simulate how these models of individuals would behave on the collective levels depending on the structure of social environments and models of social exchange, and
administer controlled group experiments and/or analyze available real world datasets.
Reversely, we should also identify interesting social/collective phenomena and investigate how they can be explained by individual decision strategies and cognitions.
Finally, these results could be used to prescribe how social environments should be structured (e.g., via institutions) to exploit the benefits of collectives and avoid pitfalls.
SPDS Retreat 2016: Introduction, Framework, Topics