Extreme idealism and equilibrium in the Hotelling-Downs model of political competition

In the classic Hotelling-Downs model of political competition there is (almost always) no pure strategy equilibrium with three or more potential strategic candidates where the distribution of voters’ preferred policies are single-peaked. I study the effect of introducing two idealist candidates who are non-strategic (i.e., fixed to their policy platform), to an unlimited number of potential strategic entrants. I present results that hold for a non-degenerate class of cases: (i) For any equilibrium, it must be that the left-most and right-most candidates (i.e., extremists) are idealists; (ii) Hotelling’s Law fails: in any equilibrium, candidates do not share their policy platforms, which instead are spread out across the policy space; (iii) Characterizations for symmetric and asymmetric single-peaked distributions of voters’ ideal policy preferences. Equilibria where many strategic candidates enter exist only if the distribution of voter preferences is asymmetric

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

E-cigarettes : the extent and impact of complementary dual-use

The highly controversial e-cigarette industry has generated considerable policy debate and mixed regulatory responses worldwide. Surprisingly, an issue that has been largely ignored is the categorisation of e-cigarettes as substitutes or (dynamic) complements for conventional smoking. We conduct an online survey of US participants finding that 37% of e-cigarette users view them primarily as complementary. We use this result along-side publicly available data to calibrate a cost-benefit analysis, estimating that complementarity reduces the potential costsavings of e-cigarettes by as much as 57% (or $3.3-4.9bn p.a.) relative to case with zero complementarity

Issues facing the modern consumer : topics in industrial organisation and decision-making

This thesis deals with specific topics within industrial organisation and consumer choice. The first chapter “Price Comparison Websites” deals with a new and growing multi-billion dollar industry that has emerged and flourished over the last two decades. Price comparison websites (PCWs) or ‘web aggregators’ are poised to benefit consumers by increasing competitive pricing pressure on firms by acquainting shoppers with more prices. However, these sites also charge firms for sales which feeds back to raise prices. I find that the introduction of a PCW increases prices for all consumers. I then consider market outcomes with competing PCWs, fee-transparency, price discrimination and costly search. The findings suggest the industry may in fact not benefit any consumers, regardless of whether they actually use the sites, and that regulatory solutions are not as simple as they may seem. The second chapter “Multi-Attribute Decision by Sampling: An Account of the Attraction, Compromise and Similarity Effects” (MADS) proposes and tests a theory that offers an explanation of the three major puzzles, known as ‘context effects’, observed in multi-attribute choice: the attraction, compromise and similarity effects. Existing models within the judgement and decision-making (JDM) literature all propose complex choice architectures that cannot explain all three effects for the same reason and in most cases, the models are only computationally solvable. Our approach is based on a single mechanism, able to explain all three effects simultaneously and permits analytic expressions for choice probabilities. MADS combines and extends three independentlydeveloped ideas from psychology: (i) that individuals compare choice alternatives with comparison items; (ii) that comparisons are based on simple dominance relations; and (iii) that comparison items are systematically influenced by the choice set faced. In a novel experimental design involving 1,200 online participants and real-world data on hotel stays, we find support for our theory’s account. In fact, our treatment was strong enough to make the classic context effects appear and disappear. It is concluded that a single-mechanism model, Multi-Attribute Decision by Sampling, can account for the three classic context effects. In the third chapter “E-Cigarettes: The Extent and Impact of Complementary Dual-Use”, we offer one of the first studies of the electronic cigarette market from an economic perspective. We apply the classic economic notion of complements and substitutes to electronic and conventional cigarettes. The work examines the validity of the common assumption that smokers adopt e-cigarettes to reduce (i.e., substitute) their consumption of traditional cigarettes. We ran an online survey to assess the motivations of users of both products, referred to as dual-users. The results show 37% of dual-users regard e-cigarettes primarily as a complement to conventional cigarettes. Using our survey together results alongside publicly-available US data, we calibrate a cost-benefit analysis and show that complementary use could wipe out up to 57% of the financial benefits e-cigarettes offer to society

When good advice is ignored : the role of envy and stubbornness

We present results from an experiment involving 1,500 participants on whether, when and why good advice is ignored, focusing on envy and stubbornness. Participants performance in skill-based and luck-based tasks generated a probability of winning a bonus. About a quarter ignored advice that would have increased their chance of winning. Good advice was followed less often when the adviser was relatively highly remunerated or the task was skill-based. More envious advisees took good advice more often in the skill-based task, but higher adviser remuneration significantly reduced this effect. Susceptibility to the sunk cost fallacy reduced the uptake of good advice

Multi-attribute decision by sampling : an account of the attraction, compromise and similarity effects

Consumers’ choices are typically influenced by choice context in ways that standard models cannot explain. We provide a concise explanation of the attraction, compromise and similarity effects. Value is assumed to be determined by simple dominance relations between choice options and sampled comparators, and selection of comparators is assumed to be systematically influenced by the choice options. In one experiment, participants viewed differing selections of market options prior to choice. The classic context effects appeared and disappeared as predicted. In the second experiment, individuals’ sampling distributions of market options were influenced by the choice set as predicted by the model

Numerical evaluation of inflationary 3-point functions on curved field space

We extend the public CppTransport code to calculate the statistical properties of fluctuations in multiple-field inflationary models with curved field space. Our implementation accounts for all physical effects at tree-level in the 'in-in' diagrammatic expansion. This includes particle production due to time-varying masses, but excludes scenarios where the curvature perturbation is generated by averaging over the decay of more than one particle. We test our implementation by comparing results in Cartesian and polar field-space coordinates, showing excellent numerical agreement and only minor degradation in compute time. We compare our results with the PyTransport 2.0 code, which uses the same computational approach but a different numerical implementation, finding good agreement. Finally, we use our tools to study a class of gelaton-like models which could produce an enhanced non-Gaussian signal on equilateral configurations of the Fourier bispectrum. We show this is difficult to achieve using hyperbolic field-space manifolds and simple inflationary potentials

CEERS: 7.7 μ{\mu}m PAH Star Formation Rate Calibration with JWST MIRI

We test the relationship between UV-derived star formation rates (SFRs) and the 7.7 ${\mu}$m polycyclic aromatic hydrocarbon (PAH) luminosities from the integrated emission of galaxies at z ~ 0 - 2. We utilize multi-band photometry covering 0.2 - 160 ${\mu}$m from HST, CFHT, JWST, Spitzer, and Herschel for galaxies in the Cosmic Evolution Early Release Science (CEERS) Survey. We perform spectral energy distribution (SED) modeling of these data to measure dust-corrected far-UV (FUV) luminosities, $L_{FUV}$, and UV-derived SFRs. We then fit SED models to the JWST/MIRI 7.7 - 21 ${\mu}$m CEERS data to derive rest-frame 7.7 ${\mu}$m luminosities, $L_{770}$, using the average flux density in the rest-frame MIRI F770W bandpass. We observe a correlation between $L_{770}$ and $L_{FUV}$, where log $L_{770}$ is proportional to (1.27+/-0.04) log $L_{FUV}$. $L_{770}$ diverges from this relation for galaxies at lower metallicities, lower dust obscuration, and for galaxies dominated by evolved stellar populations. We derive a "single-wavelength" SFR calibration for $L_{770}$ which has a scatter from model estimated SFRs (${{\sigma}_{{\Delta}SFR}}$) of 0.24 dex. We derive a "multi-wavelength" calibration for the linear combination of the observed FUV luminosity (uncorrected for dust) and the rest-frame 7.7 ${\mu}$m luminosity, which has a scatter of ${{\sigma}_{{\Delta}SFR}}$ = 0.21 dex. The relatively small decrease in ${\sigma}$ suggests this is near the systematic accuracy of the total SFRs using either calibration. These results demonstrate that the rest-frame 7.7 ${\mu}$m emission constrained by JWST/MIRI is a tracer of the SFR for distant galaxies to this accuracy, provided the galaxies are dominated by star-formation with moderate-to-high levels of attenuation and metallicity.Comment: 20 pages, 11 figures, 2 tables, submitted to Ap

Measurement of the mass and lifetime of the Ωb−\Omega_b^- baryon

A proton-proton collision data sample, corresponding to an integrated luminosity of 3 fb$^{-1}$ collected by LHCb at $\sqrt{s}=7$ and 8 TeV, is used to reconstruct $63\pm9$ $\Omega_b^-\to\Omega_c^0\pi^-$, $\Omega_c^0\to pK^-K^-\pi^+$ decays. Using the $\Xi_b^-\to\Xi_c^0\pi^-$, $\Xi_c^0\to pK^-K^-\pi^+$ decay mode for calibration, the lifetime ratio and absolute lifetime of the $\Omega_b^-$ baryon are measured to be \begin{align*} \frac{\tau_{\Omega_b^-}}{\tau_{\Xi_b^-}} &= 1.11\pm0.16\pm0.03, \\ \tau_{\Omega_b^-} &= 1.78\pm0.26\pm0.05\pm0.06~{\rm ps}, \end{align*} where the uncertainties are statistical, systematic and from the calibration mode (for $\tau_{\Omega_b^-}$ only). A measurement is also made of the mass difference, $m_{\Omega_b^-}-m_{\Xi_b^-}$, and the corresponding $\Omega_b^-$ mass, which yields \begin{align*} m_{\Omega_b^-}-m_{\Xi_b^-} &= 247.4\pm3.2\pm0.5~{\rm MeV}/c^2, \\ m_{\Omega_b^-} &= 6045.1\pm3.2\pm 0.5\pm0.6~{\rm MeV}/c^2. \end{align*} These results are consistent with previous measurements.Comment: 11 pages, 5 figures, All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-008.htm