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1.
The collection of umbilical cord blood, a source of stem cells for cancer treatment, has become a highly strategised process. STS scholarship has explored the moral/economic tensions of this case but focuses less on questions of infrastructure. This paper aims to flesh out our understanding of how stem cell collections maintain usefulness whilst clinical requirements change. It borrows from literature on studying ‘infrastructure’ to analyse qualitative data on the UK context, exploring how it might help to think of these collections not simply as banks, but as infrastructures. It attends to how maintenance relies on alertness to the shifting standards of ‘users’, and demonstrates that infrastructural thinking offers the heuristic richness needed to explore these important aspects of maintaining collections of biological material and sustaining them into the future. It thus provides a contribution to the STS literature on tissue banking and the growing interdisciplinary corpus on issues of infrastructure.  相似文献   

2.
The majority of economic decisions are forward-looking and thus involve expectations of future outcomes. Understanding the expectations that individuals have is thus of crucial importance to designing and evaluating policies in health, education, finance, migration, social protection, and many other areas. However, the majority of developing country surveys are static in nature and many do not elicit subjective expectations of individuals. Possible reasons given for not collecting this information include fears that poor, illiterate individuals do not understand probability concepts, that it takes far too much time to ask such questions, or that the answers add little value. This paper provides a critical review and new analysis of subjective expectations data from developing countries and refutes each of these concerns. We find that people in developing countries can generally understand and answer probabilistic questions, such questions are not prohibitive in time to ask, and the expectations are useful predictors of future behavior and economic decisions. The paper discusses the different methods used for eliciting such information, the key methodological issues involved, and the open research questions. The available evidence suggests that collecting expectations data is both feasible and valuable, suggesting that it should be incorporated into more developing country surveys.  相似文献   

3.
This paper investigates the welfare impact of a borrowing constraint that does not allow children to borrow against future income. In an overlapping-generations model with altruistic parents, the inability to borrow increases children’s savings and parental transfers, raising children’s welfare as well as average welfare in the short-run and in the long-run.Additionally, the borrowing constraint raises aggregate savings and, hence, physical capital. Consequently, when prices are flexible, the positive welfare impact of the constraint is higher.  相似文献   

4.
The Effect of Work Experience on Female Wages and Labour Supply   总被引:1,自引:0,他引:1  
This paper develops and implements a semiparametric estimator for investigating, with panel data, the importance of human capital and time nonseparable preferences to females when aggregate shocks are present. It provides a set of conditions for making statistical inferences about agents' expectations of their correlated future choices, from a short panel. Under the assumption that observed allocations are Pareto optimal, a dynamic model of female labour supply and participation is estimated, in which experience on the job raises future wages, and time spent off the job in the past directly affects current utility (or, indirectly through productivity in the no-market sector).  相似文献   

5.
The aggregated expectations hypothesis, described here in full for the first time, offers a new way of examining likely future outcomes based upon the most important contributor—expectations—to the individual decisions which aggregate to create these final macro-outcomes. It also offers more powerful actors, especially governments, a new tool for influencing some of those future outcomes. The core concept is that the future outcome of an issue, economic or political, will be largely determined by the expectations of those in the population affected whose aggregated individual decisions will shape that outcome.  相似文献   

6.
In this lecture, I review work addressing three questions. First, are predictions about macro stabilization policies robust to reasonable departures from rational expectations? Second, do people's expectations converge to a particular set of rational expectations? Third, if they do converge, how quickly? I discuss examples from the literature where the answer to the first question is no. The answer to the second question is that learning equilibria converge to the “standard” rational equilibria analyzed in new Keynesian models. Finally, I discuss circumstances under which the answer to the third question is very slowly. In the examples, learning is slowest and policy analysis based on rational expectations is least robust in the face of shocks that render the stakes of getting policy “right” the highest.  相似文献   

7.
Expectations about stock market movements are an important factor in models of investments and savings. To better understand consumers' financial behavior, economic surveys such as the Health and Retirement Study (HRS) ask participants to report expectations about the stock market. However, readability statistics suggest that the HRS' stock market expectations questions use relatively complex wording, which may contribute to their relatively high rates of missing responses. Here, the authors build on survey design research to improve the readability of these questions. In 2 experiments using national online panels, they test whether revising stock market expectation questions to reduce their difficulty affects respondents' (1) survey experience, as measured by percent of missing answers and ratings of question clarity and difficulty, and (2) response validity, as assessed by respondents' confidence in their answer and comparisons between expectations and stock market outcomes. In both studies, the authors' revisions improved survey experience. Unfortunately, revisions also decreased the perceived (Study 1) and actual (Study 2) validity of responses. The authors discuss implications of question revisions for the design of economic surveys.  相似文献   

8.
This study provides a new angle on the relationship between political decisions and exchange rates. We link a conventional exchange rate modeling approach to the literature on the political economy of exchange rates and studies dealing with the role of policy announcements for financial market expectations by addressing the impact of policy uncertainty on exchange rate expectations and forecast errors of professionals. Our results show that expectations are not only affected by announcements but also by the degree of uncertainty regarding the future stance of economic policy. We find that forecast errors are strongly affected by policy uncertainty compared to expectations, suggesting that the effect of uncertainty is not efficiently accounted for in market expectations. Our main findings hold for economic policy uncertainty, fiscal policy uncertainty and monetary policy uncertainty. In addition, the estimates for the Japanese yen suggest a safe haven role of the yen since higher policy uncertainty in the US results in an expected appreciation of the yen.  相似文献   

9.
Estimates of accrued‐to‐date pension liabilities (ADL) should become more widely accessible to statisticians and decision makers in the near future, in application of new SNA requirements. This raises two questions: how can such estimates be routinely produced, and what for? Microsimulation helps in answering the first question of the “how.” It allows ADL computations that take into account the complexity of pension rules. Concerning the “what for” question, it is known that ADL are not an indicator of global financial sustainability. Messages they convey are more interesting at the micro level, from a household perspective. This fosters the case for microsimulation which spontaneously generates consistent micro/macro results. We illustrate these points using the French situation as a case study. We emphasize one aspect of French reforms that may concern other countries as well: the move to price indexation and the connection it creates between sustainability and growth assumptions.  相似文献   

10.
11.
This paper studies the impact of an unfunded social security system on the distribution of altruistic transfers in a framework where savings are due to both life cycle and random altruistic motivations. We show that the effect of social security on the distribution of these transfers depends crucially on the strength of the bequest motive in explaining savings behaviour. We measure this strength by the expected weight that individuals attach to the utility of future generations. On the one hand, if the bequest motive is strong, then an increase in the social security tax raises the bequests left by altruistic parents. On the other hand, when the importance of altruism in motivating savings is sufficiently low, the increase in the social security tax could result in a reduction of the bequests left by altruistic parents under some conditions on the attitude of individuals toward risk and on the relative returns associated with private saving and social security. Some implications concerning the transitional effects of introducing an unfunded social security scheme are also discussed.  相似文献   

12.
Market participants are hypothesized to form expectations of future earnings by a process of adjustments to new earnings information while taking into account the pattern of errors in past judgements. Using an ‘adaptive expectations’ model, 140 New York Stock Exchange sample firms were classified as over- or undervalued based on earnings on announcement date versus market expectations. Comparing the risk-adjusted returns of the over- and undervalued securities for two four-year test periods, the conclusion is drawn that the securities market reacts to earnings announcements efficiently.  相似文献   

13.
In studies of large scale systems innovations or technological transitions, niches have been given a prominent role as incubators for the seeds of future technological systems. It is often argued that immature technologies rely on niches for their development, before they are able to compete in mainstream markets. This paper combines insights from economic theory and from technology studies to formulate a framework for understanding the dynamics of technological change in niches, and applies this framework to the case of fuel cell Auxiliary Power Units (APUs). We conclude that the choice of technology for APUs will be of critical importance in determining the role this market could have in shaping future developments in hydrogen and fuel cells. However, a number of factors are not strictly dependent on the technology used in fuel cell APUs. These comprise factors influencing external economies of scale, network effects, the behaviour of users and expectations.  相似文献   

14.
We examine how a remedial education programme for primary school‐age children affects parental expectations about their children's future. Using original survey data we collected in Serbia, we investigate whether expectations on labour market prospects and educational attainment change as a consequence of exposure to the Roma Teaching Assistant programme. Our results show that parents of pupils in treated schools expect higher returns to education for their children and are more likely to expect them to achieve a secondary level of education. We also investigate the possible mechanisms in place due to the characteristics of the programme: remedial education and role model.  相似文献   

15.
Most firms produce most of the time under conditions of substantial economies of scale. The division of labour, according to Adam Smith the mainspring of wealth, is intrinsically an economies of scale phenomenon. Market structure in most industries in characterized by a small number of suppliers and a larger number of customers. I explain this law of small numbers as the equilibrium of two forces: the deconcentration effect of imitation and the market spliting effect of further refinements in the division of labour by innovation. A deconcentrated market creates larger incentives for market splitting (product differentiation) by innovation than a concentrated market. But market splitting raises concentration in the market and it raises the number of different markets in the economy. Before the economies of scale of old products are fully exploited, new products are being offered which again are produced under conditions of economies of scale.  相似文献   

16.
Behavioural Economics,Hyperbolic Discounting and Environmental Policy   总被引:1,自引:1,他引:0  
This paper reviews some recent research in “behavioural economics” with an application to environmental issues. Empirical results from behavioural economics provide a reminder that human behaviour is context-dependent, implying that policy may go awry if based upon models of behaviour which are inappropriate to the contexts in which decisions are made. Recognizing that agents may, in some contexts, systematically make mistakes raises challenging questions about the role of “paternalism” in government policy. The paper considers the research into hyperbolic discounting, and examines the implications for environmental policy. We develop a model of resource management under hyperbolic discounting, which shows that if a planner is unable to commit to a policy, the temptation to re-evaluate the policy in future could lead to an inadvertent collapse in the stocks of a natural resource.  相似文献   

17.
In an article in this Journal, Edwin Mills (J Bioecon 11:296, 2009) raises to future researchers the following question: ‘[W]hy has natural selection not produced a gradual trend toward a reduction in deadly violence?’ This question has two components: (1) Has deadly violence declined? And (2) What role has been played by natural selection? This note highlights evidence bearing upon the first of these questions and offers perspectives on the second.  相似文献   

18.
Recent studies provide new empirical evidence confirming that financial development is linked to economic growth in OECD countries. Using new dynamic panel regression techniques, these appraisals indicate that within the group of high‐income countries stock market size as a measure of financial advancement contributes significantly to overall economic activity. Applying the same advanced techniques, this paper questions this conclusion by showing that the findings of these studies seem to be not only not robust with respect to adding new observations but also likely to be plagued by a severe price bias which belittles the information content of the used financial indicator (stock market capitalization). We provide evidence that anticipative price effects (i.e. expectations of future growth, reflected in current stock prices) may be driving the statistical relationship between stock market activities and economic growth in high‐income countries to a much larger extent than recent analyses of the finance– growth link in OECD countries suggest .  相似文献   

19.
We provide a cultural explanation to the phenomenon of corruption in the framework of an overlapping generations model with intergenerational transmission of values. We show that the economy has two steady states with different levels of corruption. The driving force in the equilibrium selection process is the education effort exerted by parents which depends on the distribution of ethics in the population and on expectations about future policies. We propose some policy interventions which via parents' efforts have long-lasting effects on corruption and show the success of intensive education campaigns. Educating the young is a key element in reducing corruption successfully. Journal of Economic Literature Classification Numbers: D10, J13.  相似文献   

20.
The recent trend toward convergence mergers between gas and electric utilities raises questions regarding merger analysis. Standard concentration measures do not capture adequately the ability of the merged firm to raise rivals' costs or impede their access to natural gas supplies. Estimating electricity supply curves for various time periods gives analysts an additional tool for predicting future market outcomes.  相似文献   

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