Lecture 7: Human Perceptions of Risk
Examples at start of reading
under-reaction to earthquakes by UCLA students
over-reaction to lightning vs tornadoes
Under-reactions
Human risk perception
Primary bias (size of effect bias)
Secondary bias (attentional bias)
ppl underestimate frequencies of common causes of death eg. heart disease, stroke, stomach cancer
Curved line represents bias
ppl overestimate frequencies of rare causes of death eg. food poisoning, floods
exaggerate sensational & dramatic forms of death
Events with similar actual probabilities but rated higher when ppl estimate the risk
Slovic et al
Rutgers study on assessing risk to self (unrealistic optimism)
Can try elongating time frame to risk in a lifetime
Farm management experiment
"getting on with one's life" expln
Example of seatbelt usage
it's the probability of the hazard occurring and not the severity of the damage it causes which influence one's insurance purchase decisions
ppl buy insurance for high probabiltiy/low-loss hazards instead of low-prob/high-loss hazards
criticism of Slovic et al
expln can't be generalised to non-direct, slowly developing threats posed by environmental problems
ppl's perceptions towards environment depends on whether they think of them in personal or social terms
Cognitive & perceptual biases
Optimism relates to mental health
when ppl have little perceived control, tend to ignore/discount the threat
Taylor & Brown's 3 illusions
We often believe we can influence events that are in fact determined by chance
We are overly positive about our health
We think our skills & abilities are better than they actually are
Criticism
same as for Slovic et al
Overreaction
High public concern with nuclear power
Nuclear disasters are attention grabbing
Difficulty in estimating real risks
Devastating potential effect but risk very low->sensationalised
Chernobyl
Fukushima
3 Mile Island
scientists may have disagreements over risks
scientists use "fault-tree"analysis
Scientific evaluations usually don't match public perception of risk due to diff in perceptions of what is acceptable
Psychological Stress Theory
influences on public's assessment of what is acceptable
Ability to kill in a single accident
Damage to environment & wildlife
Degree of disagreement among scientists
How equitable & voluntary the distribution of risks
Level of trust in authorities/industry
Appraisal
examples of appraisal
Types of stressors CADS
we appraise stressors and cope depending on ability
Ambient stressors
Daily hassles
Stressful life events
Cataclysmic events
Primary appraisal
Secondary appraisal
2 strategies
if have complete control to stop stressors, it's resolved
Assess magnitude of stressor & how much it impact us
assess degree of coping ability & resources available
Problem-focused
Emotion-focused
strategies (WARD F)
Avoidance of issues
Religious faith
Wishful thinking
Fatalism & learned helplessness
Tornado study
Tsunami in Banda Aceh
Alabama external locus of control-->depend on emotional based strategies
can only cope through emotion-based strategies
can cause widespread psychological trauma
Learned helplessness
can become pathological
emotion-based coping not entirely dysfunctional
inability to control the environment-->emotional responses & trauma
pathological when we don't implement solutions even if efforts to regain control might be effective
we need emotional support to overcome stressors in life
there are things beyond our control eg. Death, disasters
Cultural diff in emphasis on emotion-coping
Perceptual biases
Availability heuristic
Bounded rationalism
Gambler's fallacy
underestimate the reoccurrence of natural disasters following a disaster
Fail to recognise that individual natural disasters are independent of each other
we are limited in time & energy-->can't process all info
Rely on simplifications & heuristics
initially, believed ppl's minds are rational & make decisions after evaluating all strategies & calculating what is best
prisoners of their experience
Studies
eg. Name list study
judge probability/freq of future event based on ease with which u can imagine or recall similar events from the past
those who have experienced disaster more likely to take action
but air pollution & global warming are not very visible
Hard to conceptualise & take action for things they haven't experienced
Sims & Baumann
Weinstein
Dooley et al
residents who experienced earthquake 3 times more likely to take preventive measures
however effect wears off after several months
personal experience increases protective action
Also suggest can increase denial IF experience makes person have lower perceived control than in the past
other heuristics
Govt attention goes to problems dramatic/anxiety provoking
scientists/engineers consider oil spills & radiation from power plants less damaging overall
Should focus more resources on less dramatic but impt issues eg. (Species extinction, global warming, ozone layer)
Media
over-reporting of dramatic deaths & sensational environmental events
Use of vivid & concrete images
unshackle the "prisoner of experience"
can counter under-reaction
Decision can be influenced by how it is framed
Over-confidence of accuracy
anchoring & adjustment heuristic
eg. Estimate number of foreign cars Study
Prospect theory
eg. Public health program study
Need for Certainty
ppl more upset by losing smth than happy abt gaining the same thing
eg. London bombings by Germans
parallel with Taylor & Brown's illusions of control to maintain mental health
deny uncertainty to reduce anxiety & discomfort
due to availability heuristic, scientists may miss out certain items from being included
hence may not include all possible routes->overestimate safety
Accidents early on in a technology
Illinois internal locus of control--> resorted to problem-focused strategies
DIff between Alabama and Illinois