Der ökonomische Ansatz zur Erklärung menschlichen Verhaltens

As a typical addictive consumption, cigarettes play a special role in socio-economic activities. The dual addictive characteristics of cigarette consumption make it both an income effect and a health loss effect, which has an important impact on the operation of the social economy: on the one hand, the sociable consumption of the group can maintain or strengthen the social network may bring an increase in income, that is, the income effect; on the other hand, excessive smoking makes the body much more likely to suffer from various chronic diseases, increasing the social health expenditure, and there is a health loss effect. This literature review illustrates the relationship between cigarette consumption and rational addiction behavior. I chose the base paper written by Gary S. Becker, Michael Grossman, and Kevin M. Murphy and titled "An Empirical Analysis of Cigarette consumption." The article concentrates on the smoking addiction problem and uses statistical models to collect data in the USA. Since the smoking addiction problems gets more and more serious, the paper plays an essential role in the policy planning by understanding the cigarette demand.

In 2007 we published a paper on organ transplants that used data from 1990–2005. We proposed a radical solution of paying individuals to donate kidneys, and claimed that this would clean out the waiting list for kidney transplants in a short period of time. In this paper, we revisit the topic, and examine 14 years of additional data to see if anything fundamental has changed. We show that the main altruistic based policies implemented, such as kidney exchanges or opt out systems for organ procurement, have been unable to solve the problem of shortages. Our analysis suggests that, because of the reaction of direct living donors to increases in other sources of donations, the supply curve of kidney transplants is highly inelastic to altruistic policies. In contrast, a market in organs would eliminate organ shortages and thereby eliminate thousands of needless deaths.

Why has government grown in so many countries during the twentieth century? We present a simple model of political competition and show how different sources of the growth of government have different effects on the amount and structure of taxes, spending, and regulatory programs undertaken by the government. Those sources include: demographic shifts, more efficient taxes, more efficient spending, a shift in the “political power” from those taxed to those subsidized, shifts in political power among taxed groups, and shifts in political power among subsidized groups. We also show how the effects of each source varies according to the model of public decision-making. Based on a variety of empirical indicators of regulation, we suggest that regulation has grown from 1890 to 1990, but less rapidly than tax revenues. Regulation grew more slowly during the 1980s and, according to some measures, declined. We suggest that the long term regulatory and budgetary trends are consistent with growth in the political power of those subsidized—especially the elderly. The 1980s decline in regulation together with its growth in taxes is not consistent with any one of the theories of government growth.

Previous articleNext article No AccessPreference Formation within FamiliesGary S. BeckerGary S. BeckerUniversity of Chicago Search for more articles by this author PDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Journal of Human Capital Volume 13, Number 2Summer 2019 Article DOIhttps://doi.org/10.1086/704747 Views: 190Total views on this site © 2019 by The University of Chicago. All rights reserved.PDF download Crossref reports no articles citing this article.

Abstract Non-aqueous drilling fluids (such as synthetic-based mud) are frequently used to drill one or more sections of an oil/gas well to reduce drilling problems such as shale sloughing, wellbore stability, and stuck pipe. However, solubility of formation gas in such fluids makes early gas detection and thereby the well control process very challenging. This is of particular concern in deep offshore wells, in which large amount of gas can be dissolved in non-aqueous drilling fluids under high pressure and temperature conditions. The gas remains in solution until the bubble point is reached. Thereafter, a sudden release of gas at shallow depth can compromise wellbore and riser integrity, particularly when the gas has passed the blow out preventer installed at the seafloor. An advanced planning tool to simulate the transient multi-phase phenomena associated with gas kicks in non-aqueous drilling fluids is therefore highly desirable. This paper presents a novel and comprehensive hydraulic model with associated calculation routines and software to simulate a gas kick in non-aqueous drilling fluids. A transient drift-flux approach based on conservation of mass and momentum was applied in association with appropriate algebraic closure equations and sophisticated friction and choke models. Advanced numerical schemes, where applied previously, have been modified to handle the mass transfer between the liquid (mud) and gas phases. In addition, PVT models have been included to investigate and predict the effect of gas solubility in various types of drilling fluids. The calculation routines contained in a new software tool predict crucial parameters during well construction such as pit gain, gas break out location and void fraction, annular pressure profile, kick tolerance, choke opening, flow-out, standpipe and casing pressures. Simulation results generated using the tool are presented here for both water-based and synthetic-based muds to illustrate the impact of gas solubility on kick behavior. The tool can handle several other complexities which occur during a well control incident such as multiple influxes from one or several formations, dynamic well control (suitable for managed pressure drilling), automated choke control, sudden pump startup/shutdown, non-Newtonian drilling fluids, arbitrary wellbore path, lost circulation, etc. Applying advanced numerical schemes associated with relevant PVT models and several types of boundary conditions makes the tool comprehensive, unique, robust, and efficient for well control analysis for a variety of complex drilling scenarios, particularly deepwater wells. As such, it has the potential to enhance well control operations and well design, thereby enhancing rig safety and reducing non-productive time and cost associated with well control-related events.

We study the link between market forces, cross-sectional inequality, and intergenerational mobility. Emphasizing complementarities in the production of human capital, we show that wealthy parents invest, on average, more in their offspring than poorer ones. As a result, economic status persists across generations even in a world with perfect capital markets and without differences in innate ability. In fact, under certain conditions, successive generations of the same family may cease to regress toward the mean. We also consider how short- and long-run mobility are affected by changes in the returns to human capital.

Hydraulic modeling is an essential part of well construction planning. This task becomes even more crucial for drilling complex and challenging offshore wells with narrow drilling margins. However, the oil and gas industry still lacks a comprehensive transient hydraulic software package that can cover several advanced tasks such as conventional and dynamic well control, MPD and UBD design or testing sophisticated choke control algorithms, under one umbrella and without sacrificing much needed accuracy. In this paper, we present a novel and comprehensive hydraulic software package and its underlying models. In addition to singlephase flow, this software can also model the transient multi-phase flow behavior of drilling fluid and influx/injected gas in the wellbore. The drift-flux approach was applied in association with appropriate closure relationships, sophisticated friction and choke models. Furthermore, a user-friendly graphical user interface was developed to ease the creation of simulation cases. Through simulation scenarios, it will be shown that the new tool can accurately estimate several crucial parameters during well control such as the annular pressure profile, pump pressure, kick tolerance, flow out, pit gain or gas rising velocity, for any desired 3-D wellbore path. Applying advanced numerical schemes makes this tool fast, robust, efficient, and capable of simulating fast transients in drilling. As such, it has the potential to significantly improve well construction and drilling operations, thereby enhancing rig safety and reducing the associated nonproductive time. Introduction One of the major tasks during the well construction process is hydraulic planning and predicting important parameters such as equivalent circulating density (ECD) and kick tolerance (during a gas kick). For this purpose, an accurate hydraulic model is required. The model should not only be applicable to conventional drilling operations but also be able to handle the complexities of more innovative drilling technologies such as underbalanced drilling (UBD) or managed pressure drilling (MPD). Regardless of the technology used, well control is a permanent concern in drilling operations. Precise estimation of key parameters associated with a well control scenario including the annular pressure profile, kick tolerance, bottom-hole and surface casing pressures or gas void fraction, plays a crucial role in the well construction process. However, common kick models used in industry consider a single bubble model while assuming the gas kick and the drilling fluid to remain in separate phases with simplifications regarding gas migration, frictional pressure loss or the length of the gas column. Due to these oversimplifications and the involved uncertainties, these models tend to produce very conservative results. Another example includes the design of UBD operations in which steady-state two-phase empirical correlations are applied extensively (e.g. Beggs et al., 1973; Brill, 1985; Duns and Ros, 1963; Eaton et al., 1967; Hagedorn et al., 1965, etc.). These correlations are based on limited experimental data and are usually only applicable to Newtonian fluids. Hence, they are not necessarily valid for all simulation scenarios (Ma et al., 2016). In addition, they discard the slow transients associated with the UBD process, which makes the predictions even less reliable. The most important goal of this paper is to introduce a comprehensive hydraulic model, which can cover a large variety of drilling operations under one umbrella rather than using a particular software for each operation, thereby aiding complex well design. Background Developing a realistic hydraulic model for drilling applications that include well control events is a very complicated process due to the existence of a complex multiphase region, which usually contains a non-Newtonian drilling fluid and formation / injected gas (Ma et al., 2016). Drill string movement and eccentricity also add to the complexity of the problem. One major approach to model single-phase/multi-phase flow is using fundamental and mechanistic transport equations. Results obtained with this approach, which relies on the conservation of mass, momentum, and energy, are generally more reliable than the correlation-based models (Yuan and Zhou, 2009). Depending on the simplifying assumptions, the mechanistic models can be classified into three categories: the homogenous model, the drift-flux model, and the two or multiple-fluid model. The transient drift-flux approach is applied in this study. The homogenous model with slippage between the phases is known as AADE-17-NTCE-108 A Comprehensive Hydraulic Software Package for Drilling Operations Z. Ma, A. Karimi Vajargah*, A. Ambrus, P. Ashok, D. Chen, and E. van Oort, The University of Texas at Austin; R. May, D. Curry, J. Macpherson, and G. Becker, Baker Hughes 2 Z. Ma, A. Karimi, A. Ambrus, P. Ashok, D. Chen, E. van Oort, R. May, J. Macpherson, D. Curry, G. Becker AADE-17-NTCE-108 the drift-flux model. In this model, in order to obtain the velocity of each phase, the so-called “slip law” has to be used in conjunction with the combined momentum equation (Gavrilyuk and Fabre, 1996; Rommetveit, 1989). The drift-flux model has been frequently reported in the literature for its usage in transient multi-phase flow modeling for drilling applications (Abouie et al., 2015; Avelar et al., 2009; Nickens, 1987; Podio and Yang, 1986; Rommetveit, 1989; Rommetveit and Vefring, 1991; Udegbunam et al., 2014). Although these simulators use the same drift-flux model concept, depending on the applied numerical schemes and slip laws, significantly different results may be obtained. Two-fluid and multiple-fluid model is based on separated flow for each phase, where the slippage between the phases is considered via the interphase shear stresses. The two-fluid model needs one mass conservation equation and one momentum conservation equation for each phase (Bendiksen et al., 1991). Therefore, it is more computationally challenging. This model is also extensively used in the industry, particularly for production engineering applications (Abouie, 2015; Bendiksen et al., 1991; Shirdel and Sepehrnoori, 2012). In comparison to the two-fluid model, the drift-flux model is simpler and less computationally expensive, which provided the main motivation for applying it in this study. Recent advances in developing numerical schemes, fluid flow modeling, and drilling techniques encouraged the development of a state of the art multiphase simulator for drilling and production applications. Mathematical Model In this section, a one-dimensional drift-flux mathematical model is proposed to describe the multi-phase flow dynamics. The model consists of conservation equations of mass and momentum for multiple gas and liquid components. In addition, closure algebraic equations including slip law, and choke model, are also presented. Conservation Equations The transient dynamics of multiphase flow can be modeled using conversation equations of mass and momentum as follows:

Los análisis del régimen político tienen un insumo empírico ineludible: a comienzos del siglo veintiuno, todos los países ricos son democracias, menos los ubicados en el Golfo Pérsico y Singapur. Asimismo, las democracias en países pobres son escasas. Antes de la tercera ola de democratización, la única democracia pobre estable era India. Luego de la tercera ola, América Central es la única región pobre donde la democracia se ha difundido a escala regional. Difícilmente la correlación entre desarrollo económico y régimen político sea casual. Ello motiva a la Economía Política a identificar la relación causal, lo cual incluye al menos tres tareas:(1) establecer la dirección de la causalidad:¿ régimen causa desarrollo o desarrollo causa régimen?;(2) demarcar el mecanismo causal por medio del cual el desarrollo genera o estabiliza a la democracia; y (3) entender de qué forma otras variables, especialmente la desigualdad social y las capacidades estatales—las otras dos variables maestras de la Economía Política—, interactúan con el nivel de ingreso para generar distintas trayectorias de régimen. El presente volumen reúne once textos fundamentales para entender la relación entre desarrollo económico y régimen político.

We consider the link between parents' influence over the preferences of children, parental investments in children's human capital, and children's support of elderly parents. It may pay for parents to spend resources to manipulate children's preferences in order to induce them to support their parents in old age. Since parents invest more in children when they expect greater support, manipulation of child preferences may end up helping children and parents. A new result, which we call the Rotten Parent Theorem, demonstrates that if children are altruistic, then even selfish parents will make the optimal investment in their children's human capital.