A Behavioral Model of Conumption Patterns: The Effects of Cognitive Dissonance and Conformity

Cognitive dissonance causes people to rationalize actions that differ from their own preferences.Conformity, on the other hand, causes people to change their behavior as a result of pressure from others.This paper investigates the consequences of preference dynamic that occur when individuals rationalize their preferences, are conformists and have a minimum consumption constraint.The main results are: (1) Individuals who have a greater tendency toward conformity will rationalize their preferences to a greater degree, (2) Individuals' optimal consumption pattern will be unstable and scatter over time, (3) Average consumption in society will increase along a cyclical path and (4) An increase in either cognitive dissonance or conformity induces greater volatility of average consumption.rationality;cognitive science;consumption;volatility

Relationships as Commitment Devices: Strategic Silence

People who understand self-control problems can devise mechanisms to overcome them.In this paper, we discuss how relationships can help individuals overcome their selfcontrol problems by creating a tradeoff between desired present procrastination and undesired future procrastination.Threatening not to speak to a person who caves in can create such a tradeoff.The results depend on a limited memory assumption.We show how such interactions can explain strategic pretence, strategic ignorance, why a person would choose to punish himself after he caved in and why punishments need to increase if not adhered to immediately.strategy;bias;behavioural science

The leading effect of fluid inertia on the motion of rigid bodies at low Reynolds number

We investigate the influence of fluid inertia on the motion of a finite assemblage of solid spherical particles in slowly changing uniform flow at small Reynolds number, Re, and moderate Strouhal number, Sl. We show that the first effect of fluid inertia on particle velocities for times much larger than the viscous time scales as rootSl Re given that the Stokeslet associated with the disturbance flow field changes with time. Our theory predicts that the correction to the particle motion from that predicted by the zero-Re theory has the form of a Basset integral. As a particular example, we calculate the Basset integral for the case of two unequal particles approaching (receding) with a constant velocity along the line of their centres. On the other hand, when the Stokeslet strength is independent of time, the first effect of fluid inertia reduces to a higher order of magnitude and scales as Re. This condition is fulfilled, for example, in the classical problem of sedimentation of particles in a constant gravity field

Cognitive Procedures and Hyperbolic Discounting

"Hyperbolic discount functions are characterized by a relatively high discount rate over short horizons and a relatively low discount rate over long horizons" (Laibson 1997).We suggest two cognitive procedures where individuals perceive future utility as decreasing at a decreasing rate as a function of time.Such a perception is similar to hyperbolic discounting.The first procedure shows that individuals hyperbolically discount marginal utility from money when they follow a cognitive procedure in which they believe that their wealth might increase or decrease in each future period under the constraint of a perceived small probability that wealth will decrease below its current level.The second procedure shows that individuals hyperbolically discount expected utility from consumption when they believe that they will rationalize their actions and thus alter their utility function over time.The difference in how perceived utility changes over the short and long horizon generates the hyperbolic discounting phenomenon.We find that greater tendencies toward rationalization and greater volatility in consumption increase the hyperbolic discounting phenomenon. Although hyperbolic disc ounting is usually regarded as impulsive and irrational, Azfar (1999) and this author suggest that hyperbolic discounting may be rational in some cases.cognitive process;preferences;bias;rationality;marginalism

Stability of solitons in time-modulated two-dimensional lattices

We develop stability analysis for matter-wave solitons in a two-dimensional (2D) Bose-Einstein condensate loaded in an optical lattice (OL), to which periodic time modulation is applied, in different forms. The stability is studied by dint of the variational approximation and systematic simulations. For solitons in the semi-infinite gap, well-defined stability patterns are produced under the action of the attractive nonlinearity, clearly exhibiting the presence of resonance frequencies. The analysis is reported for several time-modulation formats, including the case of in-phase modulations of both quasi-1D sublattices, which build the 2D square-shaped OL, and setups with asynchronous modulation of the sublattices. In particular, when the modulations of two sublattices are phase-shifted by {\delta}={\pi}/2, the stability map is not improved, as the originally well-structured stability pattern becomes fuzzy and the stability at high modulation frequencies is considerably reduced. Mixed results are obtained for anti-phase modulations of the sublattices ({\delta}={\pi}), where extended stability regions are found for low modulation frequencies, but for high frequencies the stability is weakened. The analysis is also performed in the case of the repulsive nonlinearity, for solitons in the first finite bandgap. It is concluded that, even though stability regions may be found, distinct stability boundaries for the gap solitons cannot be identified clearly. Finally, the stability is also explored for vortex solitons of both the "square-shaped" and "rhombic" types (i.e., off- and on-site-centered ones).Comment: Nonlinear Dynamics, to be publishe

Ureteroscopic treatment of larger renal calculi (\u3e2 cm).

OBJECTIVES: To evaluate the current status of ureteroscopic lithotripsy (UL) for treating renal calculi of \u3e2 cm, as advances in flexible ureteroscope design, accessory instrumentation and lithotrites have revolutionised the treatment of urinary calculi. While previously reserved for ureteric and small renal calculi, UL has gained an increasing role in the selective management of larger renal stone burdens. METHODS: We searched the available databases, including PubMed, Google Scholar, and Scopus, for relevant reports in English, and the article bibliographies to identify additional relevant articles. Keywords included ureteroscopy, lithotripsy, renal calculi, and calculi \u3e2 cm. Retrieved articles were reviewed to consider the number of patients, mean stone size, success rates, indications and complications. RESULTS: In all, nine studies (417 patients) were eligible for inclusion. After one, two or three procedures the mean (range) success rates were 68.2 (23-84)%, 87.1 (79-91)% and 94.4 (90.1-96.7)%, respectively. Overall, the success rate was \u3e90% with a mean of 1.2-2.3 procedures per patient. The overall complication rate was 10.3%, including six (1.4%) intraoperative and 37 (8.9%) postoperative complications, most of which were minor. The most common indications for UL were a failed previous treatment (46%), comorbidities (18.2%), and technical and anatomical factors (12.3%). CONCLUSIONS: UL is safe and effective for treating large renal calculi. While several procedures might be required for total stone clearance, UL should be considered a standard approach in the urologist\u27s options treating renal calculi of \u3e2 cm

Neutrino neutral reaction on 4He, effects of final state interaction and realistic NN force

The inelastic neutral reaction of neutrino on 4He is calculated microscopically, including full final state interaction among the four nucleons. The calculation is performed using the Lorentz integral transform (LIT) method and the hyperspherical-harmonic effective interaction approach (EIHH), with a realistic nucleon-nucleon interaction. A detailed energy dependent calculation is given in the impulse approximation. With respect to previous calculations, this work predicts an increased reaction cross-section by 10%-30% for neutrino temperature up to 15 MeV.Comment: 4 pages, 2 fig