Learning,information processing and order submission in limit order markets

By introducing a genetic algorithm learning with a classifier system into a limit order market, this paper provides a unified framework of microstructure and agent-based models of limit order markets that allows traders to determine their order submission endogenously according to market conditions. It examines how traders process and learn from market information and how the learning affects limit order markets. It is found that, measured by the average usage of different group of market information, trading rules under the learning become stationary in the long run. Also informed traders pay more attention to the last transaction sign while uninformed traders pay more attention to technical rules. Learning of uninformed traders improves market information efficiency, but not necessarily when informed traders learn. Opposite to the learning of informed traders, learning makes uninformed traders submit less aggressive limit orders and more market orders. Furthermore private values can have significant impact in the short run, but not in the long run. One implication is that the probability of informed trading (PIN) is positively related to the volatility and the bid-ask spread.     

THE IMPACT OF LABOR MARKET REGULATION ON EMPLOYMENT IN LOW‐INCOME COUNTRIES: A META‐ANALYSIS

Controversy over labor market policy often centers on achieving a balance between preventing worker exploitation, and avoiding loss of productivity or employment through excessive regulation. Although the literature documenting the impact of labor market regulation on employment is extensive, there is a dearth of evidence on the impact of such policies in low‐income countries (LICs). Since it is easier for workers, especially women, to slip into the informal sector in LICs, regulations are likely to have stronger impacts on formal employment in these countries (but lower impacts on unemployment). We systematically reviewed available research from countries that are, or were until recently, LICs. Most studies document that more stringent labor regulations are associated with lower formal sector employment and higher informal sector employment. We also conducted a metaregression analysis of the impact of minimum wages on formal and informal employment. After controlling for publication bias, higher minimum wages are associated with lower formal employment and a higher share of informal workers.     

Global Best Practice or Regulating Fiction? Street Vending,Zero Tolerance and Conflicts Over Public Space in New York, 1980–2000

In global urban studies, different cities often serve as stand‐ins for various policy approaches. New York is closely associated with zero tolerance/quality of life policing—specifically the ways this crime‐fighting technique was used to manage and regulate public space in support of broader urban redevelopment goals. Whether celebrated or criticized, the image of New York as a city that was successful in ‘cleaning up’ public space has been exported across the globe, and has been invoked by a number of cities as they embark on their own projects to clear street vendors and other unwanted actors from public space. This article will challenge this established narrative through an examination of struggles over street vending and public space in New York during the 1980s and 1990s. It will show how the revanchist project of public space management was challenged and ultimately limited by vendors using discourses of free market populism and entrepreneurship. It demonstrates the ways in which the image of New York as a city of settled and well‐regulated public space does not tell the complete story, and how New York, like many other ordinary cities across the globe, is a city of contested spaces and uncertain regulatory effectiveness.     

Being Good Parents or Being Good Citizens: Dilemmas and Contradictions of Urban Families in Middle‐Class Enclaves and Mixed Neighbourhoods in Germany

In recent years, cities have become ever more attractive to middle‐class families. On the one hand, middle‐class families tend to withdraw into (often newly built) socially homogeneous middle‐class neighbourhoods. On the other hand, they are also known to move into inner‐city and socially mixed areas, thus triggering processes of gentrification. Academic literature has often denounced these housing choices as being either ‘separatist’ or ‘revanchist’, more broadly categorized as strategies of ‘middle‐class disaffiliation’. Although there is a grain of truth in these interpretations, the reality is certainly more complicated. In our research on middle‐class parents’ housing and neighbourhood choices as well as their patterns of neighbourhood use, carried out in each of the two types of residential area mentioned above, we have only very rarely found an explicit desire to draw boundaries that exclude those ‘beneath’ them. We rather argue that the housing choices and neighbourhood‐related activities of middle‐class family households are heavily influenced by the specific dilemmas the interviewees face as (working) urban parents. While a significant number of respondents worry about the social sustainability, justice and cohesion of urban society, they are also concerned about the future prospects of their children. Many find it difficult to reconcile these conflicting normative demands under the prevailing circumstances.     

Financialization,Urban Governance and the Planning System: Utilizing ‘Development Viability’ as a Policy Narrative for the Liberalization of Ireland's Post‐Crash Planning System

Drawing upon the Irish case, this article explores the interaction between the financialized economy and the urban planning system. While considerable scholarship has examined the financialization of real estate, it remains unclear how planning systems are being repurposed to facilitate a finance‐led regime of urban growth or how the ‘real estate–financial complex’ seeks to enact planning policy transformations that support its interests. This article explores how such actors have advanced the concept of ‘financial viability of development’ as a means of influencing the post‐crisis re‐regulation of Irish planning policy. This group has argued that housing construction in post‐crash Ireland is unviable given the high development finance costs, onerous planning gain contributions and the lack of development certainty in the planning process. As such, housing construction has been at an all‐time‐low, leading to a new crisis in affordable housing provision. In response, a complicit state has further liberalized the planning system, introducing an array of policies that are evermore facilitative of development interests. Empirical findings, based on interviews with developers, lobbyists and planners, emphasize the importance of informal access to policymakers, the wielding of ‘expert knowledge’ and media management to co‐opt the state into adopting financial viability within planning policymaking.     

The impact of margins in futures markets: evidence from the gold and silver markets

This paper investigates the impact of margin requirements on the trading activity in the gold and silver futures markets. We extend prior research in at least two ways. First, we examine the role of time to contract-expiration in the relationship between margin levels and trading activity. We make the case that such an examination will reveal the nature of the costs that margins impose on futures traders. Second, we examine the impact margins have on the makeup of traders in futures markets. The evidence indicates that trading activity becomes more sensitive to margin changes as one gets closer to contract maturity, consistent with the notion that margins impose important transaction (rather than opportunity) costs on futures traders. Further to this evidence, we find that speculators and small traders, typically illiquid, are especially sensitive to margins. The data also indicate that margins are likely to be hiked following periods of increased volatility, and reduced following periods of relative stability, suggesting that margin alterations primarily serve as insurance to the futures exchanges.     

Traders as sustainability governance actors in global food supply chains: A research agenda

Corporate actors are rapidly gaining ground as nontraditional forms of authority that shape sustainability governance efforts in global food supply chains. This paper highlights the critical, but underresearched role of traders—companies whose core business lies in the movement and exchange of agricultural commodities between producers and manufacturers—in linking corporate sustainability ambitions to on-the-ground impacts. Drawing on a systematic analysis of the major transnational corporations trading cocoa, coffee, and palm oil, we present advantages and potential pitfalls of relying on traders as implementers of sustainability governance and outline a future research agenda that focuses on producer-level impacts, changes in supply chain organization and power dynamics, and traders' interactions with state and other nonstate actors. At the intersection of supply chain management, political economy, geography, and global governance, research on traders as key sustainability governance actors also provides novel opportunities for interdisciplinary work and stakeholder engagement.     

Noise Trading and the Management of Operational Risk; Firms,Traders and Irrationality in Financial Markets*

abstract Efficient market models cannot explain the high level of trading in financial markets in terms of asset portfolio adjustment. It is presumed that much of this excessive trading is irrational ‘noise’ trading. A corollary is that there must either be irrational traders in the market or rational traders with irrational aberrations. The paper reviews the various attempts to explain noise trading in the finance literature, concluding that the persistence of irrationality is not well explained. Data from a study of 118 traders in four large investment banks are presented to advance reasons why traders might seek to trade more frequently than financial models predict. The argument is advanced that trades do not simply occur in order to generate profit, but it does not follow that such trading is irrational. Trading may generate information, accelerate learning, create commitments and enhance social capital, all of which sustain traders' long term survival in the market. The paper treats noise trading as a form of operational risk facing firms operating in financial markets and discusses approaches to the management of such risk.     

Hard and Soft Densification Policies in the Paris City‐Region

This essay is concerned with the planning and densification of suburbs, which present a huge challenge insofar as they form a large area of urbanized land that remains underexploited due to low residential density. Drawing on current research in the Paris city‐region, the essay focuses specifically on the difficulty in implementing densification policies in low‐rise suburban areas. It examines the varying degrees of densification fostered by these policies, and builds upon recent urban studies literature on suburban change to trace how suburban areas are being transformed through regulations, instruments and market dynamics associated with densification processes. What kinds of densification policy are being implemented and what are the socio‐economic, political and cultural determinants of each type of regulatory approach? This essay will attempt to answer this question via an analysis of the densification policies being put in place in the municipalities of the Paris city‐region. It will offer in turn a typology of these different policies. It shows that densification is an instrument that can be used to address local political concerns which vary greatly depending on the economic, social and geographical position of municipalities within larger urban areas.     

Insider,outsider and information heterogeneity

In financial markets, although the insider has superior information relative to the outsider, the outsider may possess some information the insider can’t precisely observe. This work investigates the impacts of information heterogeneity between the insider and outsider based on Foster and Viswanathan (1994). It shows that the less the insider knows about the outsider, the more she commits to aggressive trading, enabling her to earn more at the cost of outsider’s losses. Meanwhile, information heterogeneity improves the liquidity and benefits noise traders.     

Fake news

This analysis uses Twitter stock and options prices sampled at a 30 s frequency around the fake news announcement, of a bid for a controlling stake in Twitter stock, to investigate how noise trading and informed trading is disseminated into equity and option markets. We find reaction to the fake news occurred in the equity market, and the option market reacted with a delay. This differs from many analyses of actual news events, which found informed traders prefer the options market, and information from their trades then leaks into the equity market. We conclude uninformed traders, and those aware of the hoax, prefer to trade in equity over option markets. This result has implications for isolating informed trading around actual news events.     

Contested Development: Homeless Property,Police Reform,and Resistance in Skid Row,LA

Since the late 1990s, Downtown Los Angeles’ Skid Row has undergone private and state‐sanctioned policing practices within the fifty‐block neighborhood. These policing practices are fueled by increased commercial and real‐estate development to dispossess and contain the mostly Black homeless and housed residents. Grassroots organizations and residents have responded to gentrification‐induced policing by claiming a homeless right to property, transforming neighborhood politics. This article examines these neighborhood politics as a process of contested development. Contested development reveals the push‐and‐pull contradictions that occur when spatial difference is challenged and reproduced. Through the sphere of urban property, the contested development of property in Skid Row restores or resists the generation of spatial difference. In so doing, the claims of homeless residents and grassroots organizations to a right to property engender transformative police reforms while at the same time igniting revanchist policing methods.     

Information interaction,behavioral synchronization and asset market volatility

This paper focuses on the synchronization of trading behavior caused by interactions among traders. The study begins with an agent-based model in which most agents make investment decisions based on three types of information (neighbor, public and private information) according to their heterogeneous personal preferences. Considering the influence of the social relationship network in reality, traders in our model are connected by a complex network. We use four different types of networks. The simulated results of this model reproduce several stylized facts about the asset market. Simulated results show that when preference of traders for neighbor information increases, the level of trust among traders will gradually increase and then there will be a “leap” at a certain point. The mutual trust among traders is achieved through coupling effect in the network. Moreover, with the frequent synchronization of traders’ behavior, extreme phenomena in financial markets will emerge. In addition, our numerical simulations show that when the average degree of network is higher, behavioral synchronization will emerge at a lower level of dependence on neighbor information. The degree distribution of the network will also have a significant influence on the convergence processes of behavioral synchronization. The more heterogeneous the degree distribution is, the easier the behavioral synchronization process will occur. In our simulations, the mode of agent behavior expectation will also enhance the effect of network structure to behavioral synchronization. Finally, this paper affirms the important role of public information and learning mechanism (expectation formation mode) in the process of behavioral synchronization.     

The Slum Multiple: A Cyborg Micro‐history of an Informal Settlement in Lisbon

This article proposes a cyborg reading of the process of informal settlement by internal and postcolonial immigrants in Lisbon's periphery from the 1970s to the present. Cyborg does not stand for a neo‐organicist or cybernetic understanding of the informal city but rather for the conjunction of the multiple enactments of city life under conditions of urban informality—in this case the fourfold combination of history/migration; architecture/low‐fi technologies; inhabitation/body/memory; and governmentality/urban capital. The 40‐year event of settlement and inhabitation is presented through an ethnographic micro‐history of one neighbourhood in particular, with a strong focus on slum dwellers' life stories, on the details of the artefact‐machines they have built, their informal dwellings, and on their social and mental experience of place. Responding to recent calls for multidisciplinary ethnographies of informality, the article brings the specificity of Lisbon's informal settlements—their growth based in postcolonial rather than rural migrations—into current debates on informal urbanisms and geographies of sociotechnical urban assemblages.     

‘Don't Waste a Crisis’: Opening up the City Yet Again for Neoliberal Experimentation

This essay calls for a systematic investigation of the financial‐economic crisis as a source of new urban governance rationalities across Europe. We propose combining an understanding of neoliberalization as a variegated social phenomenon with a cultural political economy approach sensitive to the discursive dimension of variegation and the evolutionary mechanisms through which discursive variation is translated into geo‐institutional differentiation. We illustrate how this theoretical framework may help to analyse the impact of the crisis on urban governmental rationalities. Rather than offering a complete cultural political economy account of the responses of European cities to the financial‐economic crisis, we analyse how the crisis and the responses to it have been represented in discourses on urban policies and development by focusing on two discursive sites that are of strategic importance, namely OECD LEED and URBACT. Our preliminary findings suggest a re‐assemblage of existing discourses rather than the emergence of a new post‐neoliberal urban government rationality.     

Informality in developing economies: Regulation and fiscal policies

This paper proposes a unified theoretical framework where formal and informal firms coexist and face the same type of product and labor market imperfections: they have monopoly power in the goods market, they are subject to matching frictions in the labor market, and wages are determined by bargaining between large firms and their workers, through either individual or collective bargaining. Our model matches the main stylized facts on informality for developing countries and appears to be a good candidate for policy analysis. In this framework, we study the impact on informality, wages and unemployment of policies that may be used to reduce informality. We consider changes in product market regulation (PMR) and in two types of fiscal policies, labor taxes and formality enforcement. We find that lessening PMR decreases informality and unemployment simultaneously, indicating that there is not necessarily a tradeoff between informality and unemployment. The tradeoff appears when fiscal policies are used, though. Moreover, the impacts of PMR on unemployment and on wages are larger under collective than individual bargaining. With respect to wage inequality, lessening PMR reduces it, while lower taxes tend to increase the formal sector wage premium.     

COLLECTIVELY GARDENING THE URBAN PUBLIC SPACE IN MEXICO CITY: When Informal Practices Interact with the State

In recent years, a growing number of citizen-led gardens have appeared in the urban public spaces of large cities across the world. While many of these projects are initially launched informally without any support from the state, they gradually become integrated into the social fabric of the city. To understand the evolution of the formal–informal boundaries of the practice, we argue that we should be paying attention to the specific institutional contexts that frame gardeners’ interactions with public authorities. Drawing from a study of citizen-led gardens in Mexico City, we show that informal urban gardening becomes a disconnected-from-the-state practice. On the one hand, the Mexico City government has shown a growing interest in regulating urban agriculture. On the other hand, gardeners are increasingly trying to find their own ways to formalize and perennate their practice. We suggest that this disconnection between gardeners and the state is best explained by the weakness of the institutional context in which their interactions take place. A top-down policymaking process, along with the incapacity and unwillingness of the multi-leveled city government to implement policies effectively, reinforces norms of mistrust and generates low expectations among gardeners as they interact with local authorities.     

Urban Governance and the ‘European City’: Ideals and Realities in Dublin,Ireland

Throughout recent decades, a significant amount of attention has been given to the notion of the ‘European city’ within policy formation and academic enquiry. From one perspective, the ideal of the ‘European city’ is presented as a densely developed urban area with a focus on quality public transport and a more balanced social structure. More recently, however, the particular elements of the ‘European city’ associated with pedestrianized public space, urban design and image‐making strategies have become central features of entrepreneurial urban policies throughout Europe. This article undertakes an examination of the notion of the ‘European city’ in urban change in Dublin since the 1990s. Specifically, the article illustrates the degree to which a wholly positive spin on the urban design and image‐making elements of the ‘European city’ in Dublin has served as a thin veil for the desired transformation of Dublin according to neoliberal principles.     

The Regime of Informality in Neoliberal Times in Turkey: The Case of the Kadifekale Urban Transformation Project

Juxtaposing the empirical findings of a qualitative research study of an urban transformation project in the Kadifekale squatter district of Izmir with the changed nature of urban politics in a neoliberal context, this article aims to trace the manifestations of the regime of informality in Turkey. Ethnographic consideration of the motives behind these projects, the way they have been carried out and their consequences for the lives of the inhabitants points to an extended space for informal politics tactically manoeuvred by state officials of various ranks. Particularly during the last two decades, neoliberal urban policies have triggered an intensification of power discrepancies in both the vertical and horizontal dimensions and a fragmentation of community structure in the localities — mainly along socioeconomic divides. This research reveals a transition from positive/passive to negative/active uses of informality in the disposition of the state towards the urban poor when the fast and efficient conduct of urban transformation projects is in question. The characteristics of the locality as a landslide zone, the already fragmented socioeconomic structure in the neighbourhood and the dense presence of Kurdish immigrants facilitate the putting into practice of informal strategies. The immigrants who cannot define a place for themselves in the simultaneously formal and informal context of the project have been seriously disadvantaged.     

Engineering Formality: Flyover and Skywalk Construction in Mumbai

This article investigates the engineering of elevated transport infrastructure in contemporary Mumbai. It argues that the conception, construction and implementation of flyovers and skywalks in Mumbai over the past 20 years has been part of elite efforts seeking to instil a more free‐flowing, predictable and regulated city. The techniques, routines, standards and visualizations comprising these engineering schemes have promised ways of reshaping the socio‐material configurations and everyday landscapes of Mumbai into a more knowable, functional and integrated realm. The article suggests that this can be understood analytically as a means of trying to establish and maintain ‘formal’ ideals, citizens and spaces in Mumbai against wider urban contexts perceived as increasingly ‘informal’. The article thus emphasizes the importance of exploring how the ‘informal’ and ‘formal’ are actively produced and imagined against each other through material practices and procedures, and the central role of urban engineering in attempts at reconfiguring the social and political dimensions of urban life.