Evaluating the sunk cost effect

We provide experimental evidence of behavior consistent with the sunk cost effect. Subjects who earned a lottery via a real-effort task were given an opportunity to switch to a dominant lottery; 23% chose to stick with their dominated lottery. The endowment effect accounts for roughly only one third of the effect. Subjects’ capacity for cognitive reflection is a significant determinant of sunk cost behavior. We also find stocks of knowledge or experience (crystallized intelligence) predict sunk cost behavior, rather than algorithmic thinking (fluid intelligence) or the personality trait of openness. We construct and validate a scale, the “SCE-8”, which encompasses many resources individuals can spend, and offers researchers an efficient way to measure susceptibility to the sunk cost effect

Essays in behavioural economics

This thesis is a collection of three essays in behavioural economics. The first paper considers one of the most well-known cognitive biases (the “sunk cost effect”). Given its notoriety, it is perhaps somewhat surprising that there has not been many lab-based experiments that try to measure the effect. In our design we find evidence of a significant sunk cost effect (23% of the sample were subject to it) and are able to trace its determinants back to a particular aspect of intelligence (“cognitive reflection”). Moreover, we use our found sunk cost behaviour to validate a new off-the-shelf scale (the “SCE-8”) for researchers to use. The second paper then considers how a particular type of mental training (“mindfulness meditation”) can alleviate a different type of cognitive bias (“information avoidance”). Reporting evidence from a randomised-controlled trial we find that a short mindfulness treatment (two weeks, 15-minutes a day) is able to significantly reduce information avoidance in comparison to the control group. Since anyone in the population can vary in their levels of mindfulness (even if they have never meditated), these results potentially have a wide relevance. Possible mechanisms and policy implications are discussed. Finally, the third paper takes a step back from individual cognitive biases to investigate a novel way of measuring wellbeing at the macro (national) level. It asks whether the emotions of a country’s most popular songs potentially carries a signal of how happy people are actually feeling in the population. Applying emotion-detecting machine learning algorithms to the UK’s chart music, we find that the valence of the most popular song of the year can reliably predict how happy people are (with respect to the leading survey-based measure of life satisfaction)

Mindfulness reduces information avoidance

Mindfulness meditation has been found to influence various important outcomes such as health, stress, depression, productivity, and altruism. We report evidence from a randomised-controlled trial on a previously untested effect of mindfulness: information avoidance. We find that a relatively short mindfulness treatment (two weeks, 15 min a day) is able to induce a reduction in information avoidance — that is, avoiding information that may cause worry or regret. Supplementary evidence supports mindfulness’s effects on emotion regulation as a possible mechanism for the effect

Measuring national happiness with music

We propose a new measure of national valence based on the emotional content of a country’s most popular songs. We first trained a machine learning model using 191 different audio features embedded within music and use this model to construct a long-run valence index for the UK. This index correlates strongly and significantly with survey-based life satisfaction and outperforms an equivalent text-based measure. Our methods have the potential to be applied widely and to provide a solution to the severe lack of historical time-series data on psychological well-being

Mindfulness reduces information avoidance

Mindfulness meditation has been found to influence various important outcomes such as health, stress, depression, productivity, and altruism. We report evidence from a randomised controlled trial on a previously untested effect of mindfulness: information avoidance. We find that a relatively short mindfulness treatment (two weeks, 15 minutes a day) is able to induce a statistically significant reduction in information avoidance – that is, avoiding in formation that may cause worry or regret. Supplementary evidence supports mindfulness’s effects on emotion regulation as a possible mechanism for the effect

Dimensions and Global Twist of Single-Layer DNA Origami Measured by Small-Angle X-ray Scattering

The rational design of complementary DNA sequences can be used to create nanostructures that self-assemble with nanometer precision. DNA nanostructures have been imaged by atomic force microscopy and electron microscopy. Small-angle X-ray scattering (SAXS) provides complementary structural information on the ensemble-averaged state of DNA nanostructures in solution. Here we demonstrate that SAXS can distinguish between different single-layer DNA origami tiles that look identical when immobilized on a mica surface and imaged with atomic force microscopy. We use SAXS to quantify the magnitude of global twist of DNA origami tiles with different crossover periodicities: these measurements highlight the extreme structural sensitivity of single-layer origami to the location of strand crossovers. We also use SAXS to quantify the distance between pairs of gold nanoparticles tethered to specific locations on a DNA origami tile and use this method to measure the overall dimensions and geometry of the DNA nanostructure in solution. Finally, we use indirect Fourier methods, which have long been used for the interpretation of SAXS data from biomolecules, to measure the distance between DNA helix pairs in a DNA origami nanotube. Together, these results provide important methodological advances in the use of SAXS to analyze DNA nanostructures in solution and insights into the structures of single-layer DNA origami

Two-dimensional wave patterns of spreading depolarization: retracting, re-entrant, and stationary waves

We present spatio-temporal characteristics of spreading depolarizations (SD) in two experimental systems: retracting SD wave segments observed with intrinsic optical signals in chicken retina, and spontaneously occurring re-entrant SD waves that repeatedly spread across gyrencephalic feline cortex observed by laser speckle flowmetry. A mathematical framework of reaction-diffusion systems with augmented transmission capabilities is developed to explain the emergence and transitions between these patterns. Our prediction is that the observed patterns are reaction-diffusion patterns controlled and modulated by weak nonlocal coupling. The described spatio-temporal characteristics of SD are of important clinical relevance under conditions of migraine and stroke. In stroke, the emergence of re-entrant SD waves is believed to worsen outcome. In migraine, retracting SD wave segments cause neurological symptoms and transitions to stationary SD wave patterns may cause persistent symptoms without evidence from noninvasive imaging of infarction

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

How susceptible are you to the sunk cost fallacy?

Many managers are susceptible to the famous sunk cost effect, whereby they persist investing in a money-losing project even when it makes sense to invest the new money in alternative new projects. The research-based tool presented in this article enables managers to measure that susceptibility

Evaluating the sunk cost effect

We provide experimental evidence of behavior consistent with the sunk cost effect. Subjects who earned a lottery via a real-effort task were given an opportunity to switch to a dominant lottery; 23% chose to stick with their dominated lottery. The endowment effect accounts for roughly only one third of the effect. Subjects’ capacity for cognitive reflection is a significant determinant of sunk cost behavior. We also find stocks of knowledge or experience (crystallized intelligence) predict sunk cost behavior, rather than algorithmic thinking (fluid intelligence) or the personality trait of openness. We construct and validate a scale, the “SCE-8”, which encompasses many resources individuals can spend, and offers researchers an efficient way to measure susceptibility to the sunk cost effect