Policymakers around the world are exploring ways to tackle greenhouse gas emissions, but when evaluation focuses on narrow margins, policies can have unintended consequences. We study the phased introduction of London’s Ultra-Low Emissions Zone (ULEZ), a tax on highly-polluting vehicles. A simple model of location and commuting behaviour highlight four important margins of adjustment; vehicle investment, commuting mode, firm location and residential location. We study those four margins using an event study and regression discontinuity methods, and exploit the randomness of the precise borders and differential exposure of affected individuals based on their pre-existing commuting choices. We show the initial announcement of the ULEZ had large, significant positive effects on adoption of ultra-low emission vehicles. The policy had a positive effect on house prices within the zone. Individuals more exposed to the ULEZ used public transport more after the policy is introduced. Finally, we find that firms relocated outside the zone after the policy was announced. Within Greater London, response magnitudes on each margin vary substantially across space.

We analyse the degree of employer market power and labour market concentration in the UK. We investigate the relationship between employer power, labour market institutions, and labour market outcomes. We also assess the impact of four trends driving the changing nature of work that could potentially impact employer market power - working-from-home and hybrid working, the rise of the gig economy, restrictive covenants, and changes in pay-setting policies. We find that in the UK, employer market power and labour market concentration have not increased over the last twenty years, in contrast to the US. Nonetheless, there are large and persistent differences in both measures across regions, occupations, and firms. For affected workers, concentrated labour markets have a very real cost. Comparing similar workers, wages are on average 10% lower in the most concentrated labour markets compared to the least concentrated.

We present a theory of rising scale economies and stagnating productivity in a model of heterogeneous firms with imperfectly competitive product markets and firm selection. Our theory shows that scale economies arising from fixed costs versus returns to scale differ in their effect on aggregate productivity. Using UK data, we estimate a long-run increase in fixed costs and returns to scale. Our model implies that this should have significantly increased aggregate productivity, both through stronger selection of high-technical-efficiency firms and better allocation of resources across firms. However, increasing markups can offset the productivity gain. Higher markups cushion low-productivity firms’ revenues, allowing them to survive, and constrain firm output, which limits exploitation of scale economies.

We study product market power in the UK using administrative data from the UK business survey. Our data covers 1998-2014 with 40,000 firms per year accounting for 80% of UK output. We estimate firm-level markups, and present results on the aggregate and sectoral trends. We show evidence of rising markups, and increasing markup dispersion. We also show that markups and productivity are negatively related.

Which firms are using automation technologies, and what are the effects on firms and the aggregate economy? Using Italian survey data on adoption of cutting-edge technologies, such as Artificial Intelligence, I compile a set of novel findings. Firms that automate are larger, pay higher wages, and are more productive. Technology adopters grow faster once they start using automation technologies. I embed technology adoption in a heterogeneous firm model to investigate the aggregate implications of automation. The model reconciles the firm-level evidence of technology adoption boosting firm size, with the various macro studies suggesting a negative overall effect on employment.

We estimate returns to scale in the UK using firm-level data and production function estimation. We follow various methodologies, including the control function approach (e.g. Ackerberg, Caves and Frazer 2015) and the cost share approach (e.g. Gandhi, Navarro and Rivers 2020). Returns to scale is estimated over time, across industries and regions, and over the firm age and size distribution. We find evidence of returns to scale slightly above unity, and that it has risen over time.

This project investigates racial discrimination in the elite sport labour market. There is evidence of discrimination on the basis of race across many jobs, in terms of earnings and career progression. There is also significant evidence of racism in British football, among fans, in management, and in the administrative structures. I propose an analysis of earnings of British footballers, with a clear focus on the following question. Do Black players get paid the same as comparable White players? It seems reasonable to think that in the highly competitive and globally popular Premier League, racist payment regimes would be competed away. However, to the extent that decision-makers do themselves hold racist views (implicitly or not), it is possible that such outcomes occur.

There is concern about robots taking our jobs. This analysis looks at the impact of industrial robot adoption in the UK. Using a novel instrument to deal with endogeneity of robot adoption, estimates suggest that higher robot use is associated with increased employment and some evidence of a positive effect on part-time pay, contrary to evidence from other countries. However, there is a large amount of heterogeneity across industries. The results show that industrial robots have directly replaced workers in automobile manufacturing. On the other hand, they have had positive effects on other areas of the labour market such as services.