Low Immersive Virtual Experiments. Methods and Applications
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Transcript of Low Immersive Virtual Experiments. Methods and Applications
LOW IMMERSIVE VIRTUAL EXPERIMENTS.METHODS AND APPLICATIONS
ALESSANDRO INNOCENTIUniversity of Siena and LabSi
School of Social Sciences
University of Trento
December 2, 2014
To propose Low Immersive Virtual Experiments (LIVE) as tools for behavioral economics and cognitive psychology where the laboratory approach shows important limitations
To explore the potentiality of LIVE by providing some examples of applications and some preliminary findings of specifically designed laboratory studies
Talk Purpose
THE CONTEXT-FREE BIAS
HIGH AND LOW IMMERSIVE VIRTUAL EXPERIMENTS
HIVE AND LIVE APPLICATIONS
THE ALBO PROJECT
LIVE EXPERIMENTS – PRELIMINARY FINDINGS
CONCLUSIONS
Talk Outline
a) experimental situations are not really presented, but
only described through language
b) choices and decisions are only evoked, not really
performed
c) there is lack in the normal cascade of events as
actions and reactions
d) temporal frame is compressed
e) irrelevance of the context
Weaknesses of lab experiments
Many experimental economists seem to view their
enterprise as akin to silicon chip production. Subjects are
removed from all familiar contextual cues. Like the
characters 'thing one' and 'thing two' in Dr. Suess' Cat in
the Hat, buyers and sellers become 'persons A and B', and
all other information that might make the situation familiar
and provide a clue about how to behave is removed.
George Loewenstein (1999)
Lab as silicon chip production
The context-free experiment is an elusive goal
A major tenet of cognitive psychology is how all forms of
thinking and problem solving are context-dependent
The laboratory is not a socially neutral context, but is
itself an institution with its own formal or informal, explicit
or tacit, rules
Games in the laboratory are usually played without labels
but subjects inevitably apply their own labels
The context-free bias
Lecture 2 Experiments and Virtual Reality
One of the basic tenets of laboratory methodology is that the use of non-professional subjects and monetary incentives allows making subjects’ innate characteristics largely irrelevant
In some experiments, it is as if subjects take into the lab the preferences applied to real choices and stick to them with high probability
These biases or inclinations tend to override the incentive effect
Labels may give subjects clues to become less and not more rational
Methodological Biases
Labels increase experiments’ external validity with a
minimal sacrifice of internal validity
In particular, to test learning and cognitive models, it is
necessary to remind and to evoke contexts which
may activate emotions, association, similarities in the
laboratory
Labels can make subjects more or less rational in
relation to the evoked contexts.
The power of labels
Jones and Sugden Theory and Decision (2001)
Positive confirmation bias: tendency, when testing an existing belief, to search for evidence which could confirm that belief, rather than disconfirming it
The original Wason’s selection task was formulated in highly abstract terms
Correct response was facilitated by adding thematic content to the task, i.e. a cover story which accounts for the statement and gives some point to the task.
Especially the drinkers story facilitates Bayesian rationality
Labels make subjects more rational
Jones and Sudgen’s Drinkers storyDrinkers . Only people over the age of eighteen are allowed to drink alcohol in a pub in Britain. A survey is carried out of 100 people in a large public house which identifies their age and whether they are drinking alcohol or a soft drink. Each person’s details are put down on a report card with the person’s age on one side and their drinking behaviour on the other. A sample of four report cards is selected. To find out if the four people in the sample are obeying the law, look at whichever cards you wish to test the statement: [Standard statement] Every person in the sample who is drinking alcohol is also over eighteen. [Contraposed statement] Every person in the sample who is under eighteen is also drinking a soft drink
Innocenti, Pazienza and Lattarulo Transport Policy (2013)"Car Stickiness: Heuristics and Biases in Travel Choice“
Main finding: Subjects’ inclination to prefer cars over bus and metro tends to override the incentives’ effect
Laboratory behavior depends more on prior learning outside the laboratory than on gains in the laboratory
In the experiment, it is as if subjects take into the lab the preferences applied to real choices between car, bus and metro and stick to them with high probability
Labels give subjects clues to become less and not more rational
Labels make subjects less rational
Experimental literature on travel mode choice relies on studies on route choice
Common object: coordination games, i.e. the payoff each traveler can achieve is conditional on her/his ability to diverge from or to converge with other travelers’ choices
Selten et al. (2007), Ziegelmeyer et al. (2008), Razzolini-Dutta (2009) provide laboratory evidence that choices between route A and route B generate Nash equilibria
Context-free findings on travel mode
Metro Car treatment - the expected total costs of car and metro were equivalent if the share of car users was not greater than 55%;
Bus 1.0 Car treatment - the expected total costs of car and bus were equivalent if the share of car users was not greater than 55%;
Bus 0.8 Car treatment - the expected total cost of the bus was 20% lower than car expected total costs if the share of car users was not greater than 55%.
The design
Table 8 Proportion of car choices by treatment (each five periods)
Period Metro Bus 1.0 Bus 0.8 1 0.70 0.60 0.59 5 0.67 0.67 0.35
10 0.60 0.47 0.35 15 0.57 0.67 0.47 20 0.57 0.53 0.53 25 0.77 0.53 0.41 30 0.67 0.73 0.71 35 0.70 0.60 0.71 40 0.60 0.53 0.53 45 0.67 0.60 0.53 50 0.73 0.53 0.53
Total 0.68 0.58 0.50
Results – Preference for Cars
Travel mode choice is significantly affected by heuristics and biases that lead to robust deviations from rational behaviour
Travelers choose modes using behavioural rules that do not necessarily involve the minimization of total travel costs (marked preference for cars, confirm their first choice and are not inclined to change travel mode)
In repeated travel mode choice, available information is not properly processed, cognitive efforts are generally low and rational calculation play a limited role
The habit of using cars should be assumed to be relatively resistant, to the effect of economic incentives.
16
Conclusions
“WHY PEOPLE CHOOSE CARS, EVEN WHEN MASS TRANSIT WOULD SERVE THEM BETTER”
BY ERIC JAFFE (FEB 01, 2013)
WithheldName • 2 months ago
PRIVACY, CONTROL, COMFORT, FLEXIBILITY are very rational advantages to cars over buses and trains. This is the dumbest study and dumbest article I've read all week.
ChicagoStreetcarRenaissance WithheldName • 2 months ago
I look at all those hundreds of thousands of people stuck in traffic together out on the highway every morning and every evening, and here are some words that never come to mind: privacy, control, comfort, and flexibility.
WithheldName ChicagoStreetcarRenaissance • 2 months ago
When I look at city buses rolling down the street, the words that come to mind are things "passengers who have soiled themselves since their last change of clothing", "passengers who are mumbling to themselves", "passengers who are swatting at invisible flies", "passengers who are asking others for spare change", "passengers who are convicted felons", etc.
neroden • 3 months ago
FWIW, this is an Italian study and therefore only describes the biases of Italians, and in fact only of Sienna and Florence residents. There's any number of reasons why Italians might have preconceived pro-car biases, including a history of terrible urban transit. Particularly in Sienna and Florence. Try this study in London (hell to drive, everyone takes the train) and see if you get the same results. I guarantee you won't. People are using their prior biases.
Comments
One of the basic tenets of laboratory methodology in experimental economics is that the use of non-professional subjects and monetary incentives allows making subjects’ innate characteristics largely irrelevant (representative agent)
But laboratory research should highlight subjects’ preferences when applied to real choices
In these experiments labels give subjects clues that make them immerse in a context
Back to Methodology
The use of presentations with virtual reality simulations can convey this kind of context
“A Virtual Experiment is an experiment set in a controlled lab-like environment, using typical lab or field participants, that generates synthetic field cues using Virtual Reality (VR) technology.”
Fiore et al. 2009
Virtual experiments can also occurred over the web -Virtual Worlds experiments as a subset of Virtual Experiments
Virtual Experiments (VE)
High Immersive Virtual Experiments (HIVE) utilize specialized displays such as CAVE, head-mounted displays or augmented reality, which perceptually surround subjects. The individual perceives himself to be enveloped by, included in, and interacting with an environment providing a continuous stream of stimuli.
Low Immersive Virtual Experiments (LIVE) use computer screen based applications of virtual reality, such as “ad hoc” virtual simulations or virtual worlds (Second Life), to provide a weaker sense of presence.
High and Low Immersive VE
How is it possible to build virtual environments such that people respond realistically to events within them?
Mel Slater (UCL and eventLAB Barcelona)
People tend to respond with some level of realism to the virtual simulations and some level of presence occurs.
Ex. fire: another participant covered her eyes, and stepped back away from the fire, some reported feeling heat, and even smelling the smoke.
One way to think about the goal of presence in research is that to be successful it should be able to discover what would be necessary to make people actually and physically run away from a virtual fire.
Perception of presence in VR
Avatar is “a perceptible digital representation whose behaviors reflect those executed typically in real time, by a specific human being” (Bailenson and Blascovich 2004)
Digital avatars are uniquely powerful in shaping how people think and behave
The media stereotype of virtual worlds as escapist fantasies distracts us from understanding these emerging communication platforms.
Avatars and presence
Exp.1 Subjects having more attractive avatars exhibited increased self-disclosure and were more willing to approach opposite-gendered strangers
The attractiveness of their avatars impacted how intimate participants were willing to be with a stranger
Exp. 2 Subjects having taller avatars were more willing to make unfair splits in negotiation tasks than those who had shorter avatars
Subjects with shorter avatars were more willing to accept unfair offers than those who had taller avatars
Thus, the height of their avatars impacted how confident participants became.
Yee & Bailenson (2007)
Proteus effect
Background
Playing prosocial video games leads to greater subsequent prosocial behavior in the real world.
Thesis
In immersive virtual reality occupying an avatar with the superhero ability to fly increases helping behavior.
Methods
(two-by-two design) participants were either given the power of flight and were assigned one of two tasks, either to help find a missing diabetic child in need of insulin or to tour a virtual city. Before and after exposure, subjects were submitted questionnaire and trials on prosocial behavior
Findings
The results indicate that having the “superpower” of flight leads to greater helping behavior in the real world
Rosenberg, Baughman and Bailenson Plos ONE 2013http://www.plosone.org/article/info:doi/10.1371/journal.pone.0055003
Application. Prosocial behavior (HIVE)
Patil et al. (2014) Moral dilemmas are hypothetical choices regarding typically dangerous
scenarios
The possible disjunction between abstract moral judgments and actual behaviour cannot be studied experimentally. People can only be asked what they would do in the circumstances.
VR can be used to create situations in which people are exposed to specific circumstances where they have to take action
The brakes of your car fail suddenly and on your path are five people who will certainly be hit and killed. You can steer, but if you do another pedestrian will find himself on your course. Just one. What do you do: do you take action and kill one person or do you do nothing and cause five people to die?
http://goo.gl/tYsUH7
Applications. Moral dilemmas (LIVE)
Two treatments: virtual simulation vs. text format
Subjects' level of emotional arousal is collected by recording electrodermal activity
In the virtual reality setting arousal is greater and
subjects respond in a utilitarian manner choosing to take action to save the greatest number of people
In a hypothetical and therefore less emotionally charged
setting, the type of response was 'deontological': the moral aspect of the action was assessed independently from the practical consequences of the action
Design and results
Fiore et al. (2009) Virtual Experiment to elicit subjective risk perception from
wild fires and the opportunity cost of public funds allocated to prescribed burns
Subjects experience four dynamic visual simulations of specific wild fires, with varying weather and fuel conditions. Simulations are selected to represent high and low risk of fire damage
Participants experience a sense of presence, a psychological state of “being there” and take decisions closer to real behavior with cognitive constraints
Applications. Risk perceptions(LIVE)
Main objectives www.progettoalbo.itTo demonstrate that the standard tools for detecting work-related factors of risk and job-related stress (interviews and checklists) are inadequate to capture workers’ real perception To argue that low immersive simulations of work activities can nudge a better awareness of psycho-social risks in workplaces
The ALBO Project
38
Individuals are generally myopic in assessing risks and stressful situations (Tversky & Kahneman 1981, Slovic 1987, 2001)
If individuals exhibit a positive attitude to a risky prospect, they overvalue the associated benefits while under-assess the associated costs. Similarly, when their attitude is negative, the related costs are systematically overvalued (Loewenstein et al. 2001)
Reactions to risks are triggered emotionally and not determined by rational scrutiny (Damasio 1994)
Theoretical background
39
Identification of business processes
Identification of working spaces
Definition of a number of interactive scenarios, within each working space
Virtual Reality clips of the selected interactive scenarios, with the aim of identifying the most common misinterpretations and misbehaviours in terms of risk and stress perception
Procedure and methods
40
Embedment of the virtual simulations in the Adventure Game, that is an interactive gaming environment in which workers examine, interpret and assess the various virtual reality scenarios
The Gaming environment motivates people to face the challenges and find solutions to the tasks that are to be performed.
A Virtual Coach accompanies the user through the entire Adventure and facilitates the process. The Coach motivates, gives tips, and provides feedback.
Adventure game
The customised Adventure Games allow exploring the emergence and dynamics of psycho-social risks among employees
Employees, protected in their anonymity by the Virtual Reality representations, are able to formulate a critical judgement and a more objective and contextualized assessment of the situation represented in the simulation
Findings
LIVE Experiment 1 (with Cipresso and Venturini) To test differences of physiological activations in
subjects watching real movies vs. virtual movies
LIVE Experiment 2 (with Faralla)Individual risk attitude under social exposure in the lab is modified by the presence of a virtual coach
LIVE Experiments
Ob.: to verify the presence of differences in the physiological and cognitive activations while subjects watch video clips vs. virtual movies
Hp.: Exposure to video clips is associated with greater physiological activations than exposure to virtual videos.
Ts.: By inducing less emotional involvement, exposure to low immersive virtual environments may trigger cognitive restructuring mechanisms of stress perception and enhance the ability of removing heuristics and biases commonly activated in real life.
LIVE Experiment 1
Between-subject experiment10 undergraduate students2 Conditions: Real clip of a job stress situation + Virtual simulation of the same situationDetection of physiological indices during three short extracts;
Heart rate - Electromyography (EMG), i.e. electrical impulses of face muscles at rest and during contraction -Skin Conductance Level - Eye-trackingQuestionnairie:
Generalized Self-Efficacy - Locus of Control - Questions on emotional states
Design
Materials
CLIP 1
CLIP 2
CLIP 3
0
5
10
15
20
1 2 3 4 5 6 7 8 9 10 11 12
HR
0
1
2
3
4
1 2 3 4 5 6 7 8 9 10 11 12
EMG
0
10
20
30
1 2 3 4 5 6 7 8 9 10 11 12 13 14
HR
0
1
2
3
1 2 3 4 5 6 7 8 9 10 11 12 13 14
EMG
0
10
20
30
1 2 3 4 5 6 7 8
HR
0
2
4
1 2 3 4 5 6 7 8
EMG
Participants experienced greater physiological arousal during the exposure to real videos than to virtual videos
Findings can be ascribed to the type of visual representation and not to individual differences in the attribution of emotional content to the videos, not detected by the self-report questionnaires
Participants experienced a lower level of anxiety due to the weaker sense of presence caused by low immersive virtual environments
Preliminary Findings
Risk-taking with virtual coach (Faralla et al. 2013)
choice between safe and risky option two tasks: rare-loss and equiprobable-loss exposure vs. no-exposure condition observer vs. source role
Main finding: Observing others’ choices increases observer’s risk propensity
LIVE Experiment 2
Between-subject
52 undergraduate students
Two subjects randomly and anonymously paired
playing as source and observer
30 repeated choices (alternate):
15 rare (equiprobable) gains
15 rare (equiprobale) losses
Comparison between source and observer condition
Design
Tasks
Table 1 Experimental design
Rare Gain-Loss Condition Equiprobable Gain-Loss Condition
Problem 1.
Rare
Gain
Problem 2.
Rare
Loss
Problem 3.
Equiprobable
Gain
Problem 4.
Equiprobable
Loss
Safe
option
(S)
Gain 2 tokens
(EV = 2)
Lose 2 tokens
(EV = -2)
Gain 2 tokens
(EV = 2)
Lose 2 tokens
(EV = -2)
Risky
option
(R)
Gain 30 tokens
(prob. 5%)
or
Gain 1 token
(prob. 95%)
(EV = 2.5)
Lose 30 tokens
(prob. 5%)
or
Lose 1 token
(prob. 95%)
(EV = -2.5)
Gain 4 tokens
(prob. 50%)
or
Gain 1 token
(prob. 50%)
(EV = 2.45)
Lose 4 tokens
(prob. 50%)
Or
Lose 1 token
(prob. 50%)
(EV = -2.45)
LIVExp 2 - Design
Findings (no virtual coach)
Table 2. Choices by roles and option types
Sources Observers Total
Safe option 48.36 27.26 42.31
Risky option 51.64 62.74 57.69
Observers are more risk-takers than sources for both gains and
losses
Both roles are risk averse for losses and risk loving for gains
No significant difference between rare/equiprobable condition
Faster reaction time for sources
Preliminary findings (virtual coach)
Table 2. Choices by roles and option types
Sources Observers Total
Safe option 44.75 42.18 43.31
Risky option 55.25 57.82 56.69
No significant differences in risk attitudes between
observers and sources
Both roles are confirmed as risk averse for losses and
risk loving for gains
No difference in reaction time across roles
Differences between observers and sources are removed because the virtual coach make subjects’ choices less influenced by laboratory cues
Laboratory with virtual coach is perceived as an
intermediate safe environment
The Proteus Effect / deindividuation occurs in online
environments because users may adhere to
identities inferred from their avatars
The presence of virtual coach allows structuring
therapy like a protected environment
Interpretation
Main Approach to LIVE: to test if subjects’ behaviour in VE conforms to results of conventional experimentation
“Virtual experiments might be more convenient than lab experiments if he sees people behave in the same way in real-world and virtual experiments” (List 2007)
“Determining where virtual world behavior mimics real world behavior is quite important for methodological reasons.” (Castronova 2008)
The difference between virtual and laboratory experiments and between virtual and real behavior is an asset rather than a problem for experimental economics.
Final remarks
Providing more context and less simple settings
No involuntary non-verbal communication (avatars)
Wider and heterogeneous subjects pool (virtual worlds)
Tool for detecting cognitive biases and for nudging
Simulations of intertemporal choice
LIVE Experiments - PROS
Virtual situations project a game-like atmosphere
Proteus effect / deindividuation (also an asset)
It is difficult to establish subjects’ trust in computer
software
Subjects’ identity cannot be checked (virtual worlds)
LIVE Experiments - CONS
Induced-value theory: use of a reward medium allows to induce pre-specified characteristics in experimental subjects and to make subjects’ innate characteristics largely irrelevant (Smith 1992)
The central aspect of the VX methodology is a VR environment that makes participants experience a sense of presence, a psychological state of ‘‘being there.’’ This sense depends on the degree of involvement that participants experience as a consequence of focusing attention on the set of stimuli and activities generated by the VR simulation.
(Fiore et al. 2009)
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