Reinforcement learning and stochastic optimisation

At the heart of financial mathematics lie stochastic optimisation problems. Traditional approaches to solving such problems, while applicable to broad classes of models, require specifying a model to complete the analysis and obtain implementable results. Even then, the curse of dimensionality challenges the viability of conventional methods to settings of practical relevance. In contrast, machine learning, and reinforcement learning (RL) particularly, promises to learn from data and overcome the curse of dimensionality simultaneously. This article touches on several approaches in the extant literature that are well positioned to merge our traditional techniques with RL.

     

Labour Market Adjustments to Financing Conditions under Sectoral Rigidities in the Euro Area

This paper analyses empirically the response of labour market indicators to changing financing conditions in a panel of 15 euro area countries from 1999Q1 to 2015Q4. Using a local projections approach, we estimate impulse responses of three margins of sectoral labour market adjustment – employment, hours worked and real wages. Consistent with recent results in the literature, we find contractionary financing shocks to depress all three indicators of the labour market. Furthermore, responses are asymmetric depending on the sign of the shock, different in magnitude depending on the sectoral composition, and sensitive to labour market institutions such as employment protection legislation and union density. Finally, labour market institutions seem to mainly affect the relative strength of the adjustment margins and not so much the overall response of the wage bill.     

Consequences of the Treasury Single Account Policy on the Wealth of Nigerian Commercial Banks’ Shareholders

We examine the impact of the Nigerian government’s Treasury Single Account (TSA) policy to withdraw the funds of Ministries, Departments and Agencies from commercial banks. Following the economic policy uncertainty theory, we use an event study methodology to measure the impact of the TSA policy on the shareholders’ wealth. Our results reveal that the announcements and subsequent final implementation of the TSA policy caused negative abnormal returns and losses on the wealth of the commercial banks’ shareholders. This article contributes to the literature on stock market reaction to policy announcements and the unintended consequences government policy can have in an emerging economy.     

Adopting Design Thinking in Novice Multidisciplinary Teams: The Application and Limits of Design Methods and Reflexive Practices

Scholarly and practitioner literature have both described the potential benefits of using methods associated with a “design thinking” approach to develop new innovations. Most studies of the main design thinking methods—needfinding, brainstorming, and prototyping—are based either on analyses of experienced designers or examine each method in isolation. If design thinking is to be widely adopted, less‐experienced users will employ these methods together, but we know little about their effect when newly adopted. Drawing on perspectives that consider concept development as broadly consisting of a divergent concept generation phase followed by a convergent concept selection phase, we collected data on 14 cases of novice multidisciplinary product development teams using design methods across both phases. Our hybrid qualitative and quantitative analysis indicate both benefits and limits of formal design methods: First, formal design methods were helpful not only during concept generation, but also during concept selection. Second, while brainstorming was valuable when combined with other methods, increased numbers of brainstorming sessions actually corresponded to lower performance, except in the setting where new members may join a team. And third, increased team reflexivity—such as from debating ideas, processes, or changes to concepts—was associated with more successful outcomes during concept generation but less successful outcomes during concept selection. We develop propositions related to the contingent use of brainstorming and team reflexivity depending on team composition and phase of development. Implications from this study include that novice multidisciplinary teams are more likely to be successful in applying design thinking when they can be guided to combine methods, are aware of the limits of brainstorming, and can transition from more‐ to less‐reflexive practices.