Approximate maximum likelihood estimation for stochastic differential equations with random effects in the drift and the diffusion

Consider N independent stochastic processes \((X_i(t), t\in [0,T])\), \(i=1,\ldots , N\), defined by a stochastic differential equation with random effects where the drift term depends linearly on a random vector \(\Phi _i\) and the diffusion coefficient depends on another linear random effect \(\Psi _i\). For these effects, we consider a joint parametric distribution. We propose and study two approximate likelihoods for estimating the parameters of this joint distribution based on discrete observations of the processes on a fixed time interval. Consistent and \(\sqrt{N}\)-asymptotically Gaussian estimators are obtained when both the number of individuals and the number of observations per individual tend to infinity. The estimation methods are investigated on simulated data and show good performances.     

Order imbalance and stock returns: Evidence from China

We investigate the relation between daily order imbalance and return in the Chinese stock markets of Shenzhen and Shanghai. Prior studies have found that daily order imbalance is predictive of subsequent returns. On the two Chinese exchanges we find the autocorrelation in order imbalances is similar to that of the New York Stock Exchange as reported by Chordia and Subrahmanyam [Chordia, T., & Subrahmanyam, A. (2004). Order imbalance and individual stock returns: Theory and evidence. Journal of Financial Economics, 72, 485–518]. We also find a strong contemporaneous relation between daily order imbalances and returns. However, we do not find evidence that order imbalances predict subsequent returns. We attribute the difference in predicative power to differences in trading mechanisms on the two exchanges and to differences in the share turnover rates.     

LGBT Neighbourhoods and ‘New Mobilities’: Towards Understanding Transformations in Sexual and Gendered Urban Landscapes

In this article we apply insights from ‘new mobilities’ approaches to understand the shifting sexual and gendered landscapes of major cities in the global North. The empirical context is the purported ‘demise’ of traditional gay villages in Toronto, Canada and Sydney, Australia, and the emergence of ‘LGBT neighbourhoods’ elsewhere in the inner city. We reinterpret the historical geography of twentieth century LGBT lives and the associated ‘rise and fall’ of gay enclaves through the lens of the ‘politics of mobility’. In this reading, it is apparent that multifaceted movements — migration, physical and social mobility, and motility — underpin the formation of gay enclaves and recent transformations in sexual and gendered landscapes. After the second world war, LGBT communities in the global North were embedded in specific historical geographies of mobility and we trace these in the Canadian and Australian contexts. The ‘great gay migration’ from the 1960s to the 1980s has been joined by new LGBT constellations of mobility in the 2000s, and these have imprinted upon the sexual and gendered landscapes of Toronto and Sydney.     

Women and corporate boards of directors: The promise of increased, and substantive, participation in the post Sarbanes-Oxley era

Few aspects of corporate board diversity have generated the focused attention that the participation, position, and promise of women's service on the board has generated, especially in recent years. Of particular note is the extent to which women serve on large firm boards of directors (e.g., Fortune 500 firms). Increases in levels of participation have been described as glacial. While critics decry the level of participation of women on large-scale corporate boards, careful scrutiny suggests substantial progress. Concurrent with steady increases in the overall participation of women on corporate boards are increases in their presence on key board committees. Importantly, women's leadership of key board committees and their service as lead directors has improved in parallel with increases in their board memberships. These increases are particularly noteworthy in the post Sarbanes-Oxley (SOX) period. Such trends suggest the continued progress of women in assuming prominent positions in the corporate governance landscape, and provide evidence that the increasingly challenging environment in the post-SOX era has not attenuated the gains noted in the pre-SOX period.     

Analysis of Systemic Risk in the Insurance Industry

In this paper, we discuss the systemic relevance of the insurance sector. Systemic risk is defined as the propensity of a financial institution to be undercapitalised when the financial system as a whole is undercapitalised. By the law of large numbers, traditional lines of insurance with idiosyncratic non-catastrophic risks cannot be systemic. On the contrary, undiversified insurers specialised in activities whose insured risks are highly correlated with GDP are systemic. In the life insurance sector, some contractual clauses such as unhedged minimum guarantees and free options to surrender raise the chance of systemic relevance. On the contrary, life insurers satisfying the classic solvency capital requirements contribute to the liquidity of financial markets thanks to the long-termist approach of their portfolio management. Finally, using historical data in the U.S. on the contribution of different sectors to the aggregate volatility of the economy, we show that investment banking is almost twice as volatile as aggregate GDP, while insurance is one fifth as volatile as aggregate GDP. The insurance sector thus appears to be a stabilising force of the economy.     

The Health Consequences of Adverse Labor Market Events: Evidence from Panel Data

This study investigates the associations between self‐assessed adverse labor market events (experiencing problems with coworkers, employment changes, financial strain) and health. Longitudinal data are obtained from the National Epidemiological Survey of Alcohol and Related Conditions. Our findings suggest problems with coworkers, employment changes, and financial strain are associated, respectively, with a 3.1 percent (3.3 percent), 0.9 percent (0.2 percent), and 4.5 percent (5.1 percent) reduction in mental health among men (women). Associations are smaller in magnitude and less significant for physical health.     

How are Scope and Adding up Relevant for Benefits Transfer?

In this paper, we explore ways in which the theoretical constructs of scope and adding up can inform and improve the practice of benefit transfer. Specifically, we examine how the stated preference literature on scope and adding up can inform three critical steps in benefits transfer: study site selection, including studies to select for use in a meta-regression; calibrating benefit functions; and assessing transfer validity.