Matchings with externalities and attitudes

Two-sided matchings are an important theoretical tool used to model markets and social interactions. In many real-life problems the utility of an agent is influenced not only by their own choices, but also by the choices that other agents make. Such an influence is called an externality. Whereas fully expressive representations of externalities in matchings require exponential space, in this paper we propose a compact model of externalities, in which the influence of a match on each agent is computed additively. Under this framework, we analyze many-to-many matchings and one-to-one matchings where agents take different attitudes when reasoning about the actions of others. In particular, we study optimistic, neutral and pessimistic attitudes and provide both computational hardness results and polynomial-time algorithms for computing stable outcomes

A Solution to Matching with Preferences over Colleagues

We study many-to-one matchings, such as the assignment of students to colleges, where the students have preferences over the other students who would attend the same college. It is well known that the core of this model may be empty, without strong assumptions on agents' preferences. We introduce a method that finds all core matchings, if any exist. The method requires no assumptions on preferences. Our method also finds certain partial solutions that may be useful when the core is empty.Matching markets, Core, Lattice, Gale-Shapley algorithm

Social motives vs social influence: an experiment on interdependent time preferences

We report experimental evidence on the effects of social preferences on intertemporal decisions. To this aim, we design an intertemporal Dictator Game to test whether Dictators modify their discounting behavior when their own decision is imposed on their matched Recipients. We run four different treatments to identify the effect of payoffs externalities from those related to information and beliefs. Our descriptive statistics show that heterogeneous social time preferences and information about others’ time preferences are significant determinants of choices: Dictators display a marked propensity to account for the intertemporal preferences of Recipients, both in the presence of externalities (social motives) and/or when they know about the decisions of their matched partners (social influence). We also perform a structural estimation exercise to control for heterogeneity in risk attitudes. As for individual behavior, our estimates confirm previous studies in that high risk aversion is associated with low discounting. As for social behavior, we find that social motives outweigh social influence, especially when we restrict our sample to pairs of Dictators and Recipients who satisfy minimal consistency conditions

Mind in Africa, Body in Europe: The Struggle for Maintaining and Transforming Cultural Identity - A Note from the Experience of Eritrean Immigrants in Stockholm

This paper describes how individuals and groups who had crossed ‘physical, national boundaries’, and who live in a different social context make sense of their lives make sense of their lives by re-constructing their identities - of the sense of who they are, and who they want to be, which is an ongoing process. This is done by narrating the experiences of African men and women who live in Sweden and who struggle to both maintain their cultural identity and at the same time change aspects in their culture due to the context in which they find themselves. Maintaining cultural identity and transforming aspects of that identity therefore constitute the main thrust of the paper. Some of the ways through which immigrants claim to maintain their identity are practices and routines that they repeatedly and consistently perform as if these were uniform both in the host country and in the country of origin. But it is exactly within this premise that ‘maintaining’ an identity is defined in this paper. However, the routines, or practices may have different meanings or significance to different actors, different audience, and especially for the main beneficiaries, in a particular context. In this paper, I will narrate how ‘maintaining’ cultural identity is understood and practiced by Blin (Eritrean) immigrants in Stockholm, Sweden, when they solemnly perform a cultural rite called blessing (gewra) in weddings. The paper is based on a participant observation of weddings from 1992 to 2001 in Stockholm, Sweden, when the Blin speaking people perform the blessing rite, enjoy doing it, show to the audience how they maintain ‘who they are’, and perhaps symbolically confirm their unity with the Blin community. The main actors are the elderly and the bridegroom, both sine qua non if the rite is to get its legitimacy. Thus, the blessing rite is an example of being Eritrean in Sweden for its performers. The concept of identity and identity construction has become an important concept to deal with such demands for ‘maintaining’ and 'transforming' identities. Even though maintaining identity is encouraged in the Swedish social policy, transformation of that identity comes through demands that are widely accepted as modern values, such as egalitarianism, gender equality and individualism – leading to issues of diversity at different levels. If one strictly defines the meaning of the blessing rite, one can find that the meaning sometimes may not be consonant with the so-called modern values but that the people then provide symbolic significance to the rite.Blessing rite, Blin community, Culture maintenance, Identity construction, Immigrant

The World Bank’s Prototype Carbon Fund and China

As the first global carbon fund, the World Bank’s Prototype Carbon Fund (PCF) aims to catalyze the market for project-based greenhouse gas emission reductions while promoting sustainable development and offering a learning-by-doing opportunity to its stakeholders. Since the inception in 2000, the PCF has engaged in a dialogue with China to get it to sign up as a host country, because the World Bank and other international and bilateral donors expect great potential of the clean development mechanism (CDM) in China and feel the significant need for building CDM capacity in China to enable it to gain more insight into the CDM and increase its capacity to initiate and undertake CDM projects. This paper first discusses why China had hesitated to sign up as a host country of PCF projects until September 2003. Then the paper explains what has led China to endorse the PCF projects. The paper ends with discussions on the implications of the PCF’s offering prices for the emerging global carbon market.Carbon prices, Carbon market, China, Prototype Carbon Fund, The World Bank

A Meta-Analysis of the Willingness to Pay for Reductions in Pesticide Risk Exposure

The use of environmental policy instruments such as eco-labelling and pesticide taxes should preferably be based on disaggregate estimates of the individuals’ willingness to pay (WTP) for pesticide risk reductions. We review the empirical valuation literature dealing with pesticide risk exposure and develop a taxonomy of environmental and human health risks associated with pesticide usage. Subsequently, we use meta-analysis to investigate the variation in WTP estimates for reduced pesticide risk exposure. Our findings show that the WTP for reduced risk exposure is approximately 15% greater for medium, and 80% greater for high risk-levels, as compared to low risk levels. The income elasticity of pesticide risk exposure is generally positive, although not overly robust. Most results indicate that the demand for human health and environmental safety is highly elastic. We also show that geographical differences, characteristics of the survey, and the type safety device (eco-labelling, integrated management, or bans) are important drivers of the valuation results.Pesticide risk, Willingness to pay, Meta-analysis

Assessing the Effectiveness of Tradable Landuse Rights for Biodiversity Conservation: An Application to Canada's Boreal Mixedwood Forest

Ecological reserve networks are an important strategy for conserving biodiversity. One approach to selecting reserves is to use optimization algorithms that maximize an ecological objective function subject to a total reserve area constraint. Under this approach, economic factors such as potential land values and tenure arrangements are often ignored. Tradable landuse rights are proposed as an alternative economic mechanism for selecting reserves. Under this approach economic considerations determine the spatial distribution of development and reserves are allocated to sites with the lowest development value, minimizing the cost of the reserve network. The configuration of the reserve network as well as the biodiversity outcome is determined as a residual. However cost savings can be used to increase the total amount of area in reserve and improve biodiversity outcomes. The appropriateness of this approach for regional planning is discussed in light of key uncertainties associated with biodiversity protection. A comparison of biodiversity outcomes and costs under ecological versus economic approaches is undertaken for the Boreal Forest Natural Region of Alberta, Canada. We find a significant increase in total area protected and an increase in species representation under the TLR approach.Biodiversity conservation, Reserve design, Tradable landuse rights

Essays In Two-Sided Markets With Intermediaries

In this thesis, I study the two-sided marketplaces with intermediaries that can facilitate matching, search and trades. The first chapter considers the welfare and distributional consequences of introducing the student-proposing deferred acceptance mechanism in a model where schools have exogenous qualities and the benefit from attending a school is supermodular in school quality and student type. Unlike neighborhood assignment, deferred acceptance induces non-positive assortative matching where higher-type students do not necessarily choose neighborhoods with better schools. Student types are more heterogeneous within neighborhoods under deferred acceptance. Assuming an elastic housing supply, deferred acceptance benefits residents in lower-quality neighborhoods with more access to higher quality schools. Moreover, more parents will `vote with their feet\u27 for deferred acceptance, other things equal, than for neighborhood assignment. The second chapter studies a search platform in a setting where buyers search for sellers directly or through a platform with lower search costs, and the platform charges both sides for the transactions it facilitates. While many intermediaries attract as many users as possible by lowering search cost, potential buyers also care about how attractive the sellers available via the intermediary are, not just the number. A search platform\u27s strategy is determined by the coexisting positive and negative cross-group externalities: (i) while buyers appreciate more choices of sellers available on the platform, (ii) increasing the number of available sellers makes the search for low-priced and high-value sellers harder due to an unfavorable price dispersion. A platform optimally adopts a threshold strategy of targeting sellers with lower costs to balance the competing externalities. The third chapter studies intermediation in a buyer-seller network with sequential bargaining. An intermediary matches traders connected in a network to bargain over the price of heterogeneous goods and has the freedom to charge each side commission. A profit-maximizing middleman can help eliminate trading delays but limits trade executed that are not surplus maximizing. When the middleman competes with the buyers and sellers being matched through an exogenous search process, she matches buyer and seller pairs that are selected less often by the exogenous search process

Profiling Tourists for Balanced Utilization of Tourism-Based Resources in Kenya

Kenya is predominantly a nature-based tourism destination with wildlife (concentrated in the southern part of the country) and beaches (along the Indian Ocean) accounting for over 85% of the international tourists visiting the country. Other attractions are based on the physical landscape of the country and the culture of the people. Unfortunately, the full potential of culture-based attractions has not been exploited. The over-concentration of tourism activities in wildlife protected areas and on the coastal zone has had inherent problems that include severe environmental degradation. The less visited attractions stand the risk of neglect and could be eroded from the nation’s heritage with time. There is need to diversify tourism activities and spread them to other parts of the country by putting more emphasis on non-traditional ones such as cultural excursions. This research profiles tourists based on their preferences as assessed from the number of days they spend at different attraction sites. By associating the characteristics of tourists with various attractions, consumer preference profiles were established. Length of stay, presence of children, travel party size and gender are some of the significant factors that determined the profiles. Profiles can be used in encouraging proportionately more tourists with greater affinity for non-traditional attractions. Besides gender, other factors such as socio-economic status and whether one is travelling as a couple or not, turned out to be significant variables in influencing the resulting expenditure levels.Tourist profiles, Attractions, Culture, Expenditure, LISREL, Kenya