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Gretchen Chapman - Carnegie Mellon University. Pittsburgh, PA, US

Gretchen Chapman

Professor and Department Head | Carnegie Mellon University


Gretchen Chapman's research combines judgment and decision-making with health psychology.


Gretchen Chapman has been a Professor in Social & Decision Sciences since 2017. Prior to joining the faculty at CMU, Dr. Chapman was a Distinguished Professor of Psychology at Rutgers University where she served as Department Chair of Psychology and Acting Co-Director of the Center for Cognitive Science. She is the recipient of an APA early career award and a NJ Psychological Association Distinguished Research Award, a fellow of APA and APS. She is a former senior editor at Psychological Science, a past president of the Society for Judgment & Decision Making, the author of more than 100 journal articles, and the recipient of 20 years of continuous external funding.

Areas of Expertise (8)

Health Behavior

Decision Research

Field Experiments‎

Decision Processes

Risk Preferences

Default Effect

Behavorial Game Theory

Public Health Analysis

Media Appearances (6)

Workplace requirements a strong tool to reduce COVID-19 risk: expert

McKnight's Senior Living  online


But, Chapman said, mask-wearing is an example of the “power of situation.” “We behave in different ways in different situations depending on the context. The important part of context is social norms, or what other people are doing,” she said. “If we can structure the situation so mask-wearing looks like the normative thing to do, then a lot of folks are going to follow along and follow that norm.”

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It’s Time to Wear a Mask Again, Health Experts Say

New York Times  print


"Realistically, not everyone in the United States — or a certain city — will wear a mask. In fact, you might find yourself the only person in a store or on a plane who’s wearing one. Don’t let that discourage you. For one thing, remember that no one is thinking about you as much as you think they are. In social psychology, this is called the spotlight illusion, said Gretchen Chapman, a professor of social and decision sciences at Carnegie Mellon University. 'I may feel that everyone’s staring at me because I’m wearing a mask, but chances are that’s like the 11th thing on their list to worry about,' she said. What’s more, Dr. Chapman said, 'There are lots of situations in life where we do something that makes us feel awkward, but if we think it’s important enough, we do it anyway.'”

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Scaling the cost of government programs using a cost-per-person price tag improves comprehension by the general public

Phys Org  online


"When President Trump wanted to spend $10 billion on the border wall, conservatives were saying it was a great idea while liberals were saying why spend that much money on a wall," said Gretchen Chapman, department head and professor of Social and Decision Sciences at CMU. Chapman is the senior author on the study. "This got our team thinking, and we began by asking how big is $10 billion, and how do people really think about such a really big number?"

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Why are masks such a big deal for so many? Psychologists have thoughts

NPR  online


A Florida judge struck down the federal travel mask mandate last Monday, and while companies aren't being forced to drop their mandates, many have. Meanwhile, the Omicron subvariant BA.2 now accounts for 75 percent of new COVID cases in the U.S. To mask or not to mask continues to be a divisive question. We get into the psychology of why. Dr. Anthony Fauci, Gretchen Chapman, and Steven Taylor join us for the conversation.

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America’s Flu-Shot Problem Is Also Its Next COVID-Shot Problem

The Atlantic  online


We don’t have to resign ourselves to this fate. Flu shots have had their failures, but they’ve clearly had their successes too. Roughly half of American adults don’t get an annual flu shot. The other half do. “The best predictor of whether you got a flu shot this year is if you got one last year,” says Gretchen Chapman, a cognitive scientist who studies vaccine behaviors at Carnegie Mellon University. To at least a degree, we have been doing a few things right.

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Children's Risk Of Serious Illness From COVID-19 Is As Low As It Is For The Flu

NPR  online


"If you stop going into stores because you're terrified you'll run into an unmasked person, that's probably overreacting," says Gretchen Chapman, a psychology professor who studies health conundrums like this at Carnegie Mellon University.

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Gretchen Chapman Publication



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Will People Accept a COVID 19 Vaccine? With Gretchen Chapman, PhD Gretchen Chapman, PhD - ​​



Industry Expertise (2)

Health and Wellness

Public Policy

Accomplishments (4)

Distinguished Research Award, New Jersey Psychological Association (professional)


Society for Medical Decision Making Award for Outstanding Paper by a Young Investigator (professional)


American Psychological Association Distinguished Scientific Awards for an Early Career Contribution to Psychology (professional)


Division of Experimental Psychology, American Psychological Association Award (professional)


Education (2)

University of Pennsylvania: Ph.D., Psychology 1990

Bryn Mawr College: A.B., Psychology 1985

Affiliations (7)

  • Association for Psychological Science : Fellow
  • American Psychological Association : Fellow
  • Society for Judgment & Decision Making : Past President
  • Psychological Science : Former Senior Editor
  • European Association of Decision Making : Member
  • The Psychonomic Society : Member
  • Society for Medical Decision Making : Member

Languages (1)

  • English

Event Appearances (3)

Panelists for session on “Leveraging psychological science to promote COVID-19 vaccine uptake during a public health emergency.”

(2022) Association for Psychological Science Meeting  

Panel presentation "Large numbers cause magnitude misinterpretation: The case of government expenditures"

(2022) AAAS Meeting  

Panelist "Psychology of vaccine hesitancy"

(2021) Association for Health Care Journalists, Summit on Mental Health  Virtual

Research Grants (3)

"Lay understanding of vaccine efficacy"

Doctoral Dissertation Research in DRMS $22,545

Gretchen Chapman, PI; Alison Butler, co-PI. NSF SES-2149406, 02/01/2022 – 1/31/2023

“Improving pediatric donor heart availability through in-depth collaboration between behavioral and clinical sciences”

Enduring Hearts Foundation $159,574

Justin Godown, PI; Gretchen Chapman, co-I. 7/01/2021 – 6/30/2023

“Don't Throw Your Heart Away: Decision Processes Explain the High Discard Rate of Pediatric Donor Hearts,”

National Heart, Lung, and Blood Institute $200,064

Alison Butler, PI; Gretchen Chapman, Faculty Mentor. NIH F30 HL152526-01, 7/15/2020 – 7/24/2024,

Articles (7)

Information and Vaccination: When Does Communication Reduce Hesitancy?


2023 Although vaccines are the most effective tool for reducing the morbidity and mortality caused by infectious disease, their impact is reduced due to vaccine hesitancy and insufficient uptake. Because delaying or declining vaccination is correlated with beliefs that vaccines are unsafe and ineffective, a traditional approach to deal with these issues is health education, which is widely adopted by policymakers and organizations in a variety of health domains. Studies on information interventions, however, have a mixed track record, with some showing an effect on beliefs, attitudes, intentions, or behavior and others showing no effect and a few even backfiring. Given these mixed findings, it is relevant to identify the conditions under which information is more (or less) successful in creating meaningful change. In this chapter, we synthesize evidence from information provision interventions to fill this gap in the literature. To that end, we first conceptualize what we mean by ‘information’ in the context of information provision interventions. In addition, we classify information provision interventions based on informational (i.e., message content) and non-informational elements (e.g., message source) that researchers have experimentally manipulated.

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Perceptions of pediatric deceased donor consent: A survey of organ procurement organizations

Pediatric Transplantation

2023 Background Children awaiting transplantation face a high risk of waitlist mortality due to a shortage of pediatric organ donors. Pediatric donation consent rates vary across Organ Procurement Organizations (OPOs), suggesting that some OPOs might utilize more effective pediatric-focused donor recruitment techniques than others. An online survey of 193 donation requestor staff sheds light on the strategies that OPO staff utilize when approaching potential pediatric deceased organ donors. Methods In collaboration with the Association of Organ Procurement Organizations, the research team contacted the executive directors and medical directors of all 57 of the OPOs in the US. Of these, 51 OPOs agreed to participate, and 47 provided contact information for donation requestor staff. Of the 379 staff invited to participate in the survey, 193 provided complete responses.

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A randomized trial of behavioral Nudges delivered through Text messages to increase influenza vaccination among patients with an upcoming primary care visit

American Journal of Health Promotion

2023 Purpose To evaluate if nudges delivered by text message prior to an upcoming primary care visit can increase influenza vaccination rates. Design Randomized, controlled trial. Setting Two health systems in the Northeastern US between September 2020 and March 2021. Subjects 74,811 adults. Interventions Patients in the 19 intervention arms received 1-2 text messages in the 3 days preceding their appointment that varied in their format, interactivity, and content.

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Signals of Virtue and When they Backfire: How Honesty Badges Provide Cover for Dishonesty


2023 Organizations have begun using publicly-visible badges to promote ethical behaviors, such as workers’ contributions to colleagues’ projects and scientists’ engagement in transparent research practices. Across six experimental online studies, we evaluate whether badges incentivize ethical behavior as proposed (N= 2047). Our results indicate that, in some instances, badges’ signaling value undermines their ability to promote honesty. When it is possible to earn an honesty badge while still engaging in dishonest behavior, badges backfire by providing cover to dishonest individuals. Under “opaque badges,” workers will do only what is needed to earn a badge and behave more dishonestly than they would when no badge is available. Moreover, opaque badges make workers appear more honest to observers, leading them to down-weight worker behavior that would otherwise arouse suspicion. We show that removing badges’ ability to provide cover–by clarifying what workers did to earn them–can attenuate these effects.

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The impact of donor consent mechanism on organ procurement organization performance in the United States

The Journal of Heart and Lung Transplantation

2023 BACKGROUND Lack of donor organ availability represents a major limitation to the success of solid organ transplantation. The Scientific Registry of Transplant Recipients (SRTR) publishes performance reports of organ procurement organizations (OPO) in the United States, but does not stratify by the mechanism of donor consent, namely first-person authorization (organ donor registry) and next-of-kin authorization. This study aimed to report the trends in deceased organ donation in the United States and assess the regional differences in OPO performance after accounting for the different mechanisms of donor consent. METHODS The SRTR database was queried for all eligible deaths (2008-2019) which were then stratified based on the mechanism of donor authorization. Multivariable logistic regression was performed to assess the probability of organ donation across OPOs based on specific donor consent mechanisms. Eligible deaths were divided into 3 cohorts based on the probability to donate. Consent rates at the OPO level were calculated for each cohort.

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Crowdsourcing interventions to promote uptake of COVID-19 booster vaccines


2022 Background COVID-19 booster vaccine uptake rates are behind the rate of primary vaccination in many countries. Governments and non-governmental institutions rely on a range of interventions aiming to increase booster uptake. Yet, little is known how experts and the general public evaluate these interventions. Methods We applied a novel crowdsourcing approach to provide rapid insights on the most promising interventions to promote uptake of COVID-19 booster vaccines. In the first phase (December 2021), international experts (n = 78 from 17 countries) proposed 46 unique interventions. To reduce noise and potential bias, in the second phase (January 2022), experts (n = 307 from 34 countries) and representative general population samples from the UK (n = 299) and the US (n = 300) rated the proposed interventions on several evaluation criteria, including effectiveness and acceptability, on a 5-point Likert-type scale.

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Using analogy-based messages to influence attitudes toward workplace COVID-19 vaccination mandates


2022 Workplace mandates are a highly effective strategy for increasing COVID-19 vaccination rates, and their adoption by United States employers grew throughout 2021. Still, public opinion on these mandates has remained starkly polarized. Drawing from the widespread use of analogies in health communication during the pandemic, we investigated whether analogies to widely-accepted workplace safety rules could affect attitudes toward vaccination mandates. In a survey experiment conducted in September-October 2021, 1194 respondents were randomized to one of three messages about workplace COVID-19 vaccination mandates that included (1) no analogy;(2) an analogy to workplace hard hat policies; or (3) an analogy to workplace smoking bans. Only the smoking analogy increased support for (b= 0.41; p

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