Results

CEP discussion paper

Cultural exception? The impact of price regulation on prices and variety in the market for books

Fixed book price (FBP) agreements are a form of resale price maintenance applied to books in various countries. FBP restricts retail price competition with the aim of promoting book production variety. Yet, despite its p...Read more...

Blog

LSE USA Politics and Policy:

The lasting impact of 9/11 on Muslim integration in America

With ongoing global debates on immigration, integration, and rising Islamophobia, understanding the long-term social impacts of historical events is more important than ever. Shadi Farahzadi studies the effects of the 9/...Read more...

CentrePiece article

in brief... Successful caps on fees disprove the idea that it’s unwise to meddle with free markets

Jan David Bakker and Nikhil Datta show how the success of a reform of letting agents’ fees was partly due to their hidden nature....Read more...

CentrePiece article

Revving up wages: How rising productivity has benefited car industry workers

Fast productivity growth in the UK car industry led to staff in the sector earning about 37% more than the average manufacturing employee by the 2010s. But Andreas Teichgraeber and Tim Obermeier show that while wages wen...Read more...

CEP discussion paper

Market power, growth and wealth inequality

In recent decades, the United States has experienced a notable rise in markups, a slowdown in productivity growth, and an increase in wealth inequality. We present a framework that unifies these trends into a common driv...Read more...

CEP discussion paper

What fueled the illicit opioid epidemic? New evidence from a takeover of white powder heroin markets

In recent years, the majority of drug overdose deaths in the U.S. have involved illicitly-produced opioids (primarily heroin and fentanyl), overtaking prescription opioids as the main driver of the opioid epidemic. In th...Read more...

Blog

Vox EU:

New approaches to measure (increasing) concentration in Europe

Concentration (the share of a market's output produced by its largest firms) is a key proxy for measuring market competition. This column introduces a cross-country dataset to measure concentration at the industry level ...Read more...

Blog

Vox EU:

The evolution of gender in the labour market

Despite significant progress in closing the gender gap in earnings, work remains highly gendered, with women continuing to participate less in the workforce, work fewer hours, and face persistent wage disparities. This c...Read more...

CEP discussion paper

Industry concentration in Europe: Trends and methodological insights

Concentration - the share of an industry's output accounted for by its largest firms and a frequently used proxy of competition - has increased in European countries. This paper provides evidence about this development b...Read more...

Blog

The Conversation:

Successful caps on English letting agents' fees disprove the idea that it's unwise to meddle with free markets

Five years ago, the UK government enacted the first legislation regulating prices in the English rental market since the 1960s. The Tenant Fees Act 2019 didn't interfere with what landlords can charge tenants in rent, bu...Read more...

CEP discussion paper

The integration penalty: Impact of 9/11 on the Muslim marriage market

Major sociopolitical events can have lasting impacts on integration through changing marriage preferences. Marriage markets, due to their unregulated nature, both reflect and affect integration in society. I use 9/11 as ...Read more...

Journal article

Handbook of Labor Economics:

Chapter 9 - Crime and the labor market

The economics of crime has emerged as a critical field over the past 30 years, with economists increasingly exploring the causes and consequences of criminal behavior. This chapter surveys key contributions and developme...Read more...

CEP discussion paper

Global robots

The diffusion of automation technology raises questions about the future of work, leading to calls for policy interventions. The ongoing debate centers on the decisions made by technology adopters. In this paper, I study...Read more...

Journal article

International Journal of Industrial Organization:

VAT pass-through and competition: Evidence from the Greek islands

We examine how competition affects VAT pass-through in isolated oligopolistic markets as defined by the Greek islands. Using daily gasoline prices and a difference-in-differences methodology, we investigate how changes i...Read more...

Journal article

Review of Income and Wealth:

Insecurity on the Labor Market

There is a common feeling that life has become more insecure over time. I here consider this proposition with respect to the labor market. I first discuss how labor-market insecurity might be measured, and then its poten...Read more...

Blog

LSE Business Review:

Achieving net zero by 2050 requires changes to the UK skills landscape

As COP29 brings climate action into focus, it's clear that policy must go beyond carbon trading and finance. To make net zero a reality, the workforce must be equipped with the right skills. Aadya Bahl examines what this...Read more...

Journal article

Journal of Economic Geography:

When market access gains do not spur urban growth

We revisit the natural experiments of division and unification of Germany. The negative shock to local market access following the division of Germany led to a fast and strong downward adjustment of the size of West Germ...Read more...

CEP discussion paper

Job displacement, remarriage and marital sorting

We investigate how job displacement affects whom men marry and study implications for marriage market matching theory. Leveraging quasi-experimental variation from Danish establishment closures, we show that job displace...Read more...

CEP discussion paper

Crime and the labor market

The economics of crime has emerged as a critical field over the past 30 years, with economists increasingly exploring the causes and consequences of criminal behavior. This chapter surveys key contributions and developme...Read more...

CentrePiece article

Better work: whose business is it?

Regulating the labour market is essential to address the inherent imbalance of power between employers and employees. But that doesn’t necessarily mean that the state needs to intervene more than it already does. Alan Ma...Read more...

Journal article

Demography:

Population Growth, Immigration, and Labor Market Dynamics

This article provides a first synthesis of population flows and labor market dynamics across immigrant and native-born populations. We devise a novel dynamic accounting methodology that integrates population flows from t...Read more...

CEP discussion paper

Trade and the end of antiquity

What caused the end of antiquity, the shift of economic activity away from the Mediterranean towards northern Europe? We assemble a large database of coin flows between the 4th and 10th century and use it to document the...Read more...

CEP discussion paper

Asymmetric pass-through and competition

We study the retail price pass-through of four major tax changes in petroleum products using daily pricing data from gas stations on small Greek islands. We find that (i) the pass-through of the tax hikes is five times h...Read more...

Journal article

Oxford Open Economics:

Spatial disparities across labour markets

We consider disparities across local labour markets in Great Britain. Disparities in wages and employment rates are large and persistent, although smaller than 20 years ago. These disparities largely reflect the concentr...Read more...

Journal article

Oxford Open Economics:

Labour market inequality

Wage and earnings inequality has been on the rise in the United Kingdom (UK) since the late 1970s/early 1980s, and with faster increases than comparator countries, it is now one of the countries with the highest levels o...Read more...

CEP discussion paper

Avenging the tenants: Regulating the middle man's rents

We explore the role of intermediaries in the rental market. Using novel UK data on fees letting agencies charged to both tenants and landlords, combined with a matched property-agency listings dataset, we study the effec...Read more...

CEP discussion paper

An engine of (pay) growth? Productivity and wages in the UK auto industry

When labour market competition is imperfect, positive industry (and firm) productivity shocks can be passed through to workers in the form of higher wages. We document how the UK auto industry, following a period of decl...Read more...

CEP discussion paper

The wage of temporary agency workers

Using French administrative data, we estimate the wage gap distribution between in-house and temporary agency workers working in the same establishment and the same occupation. The average wage gap is about 3%, but the g...Read more...

Journal article

Journal of Labor Economics:

The Decline in Rent Sharing

The evolution of rent sharing is studied. Based on a panel of the top 300 publicly quoted British companies over 35 years and using excess stock market returns to patenting activity as an instrument for economic rents, t...Read more...

Journal article

:

Historical Differences in Female-Owned Manufacturing Establishments: The United States, 1850–1880

We characterize female-owned manufacturing establishments using newly digitized manuscripts from the US Census of Manufactures (1850, 1860, 1870, 1880). Female-owned establishments were smaller than male-owned establishm...Read more...

CEP discussion paper

Gender, careers and peers' gender mix

We use Italian Social Security data to study how the gender composition of a worker's professional network influences their career development. By exploiting variation within firms, occupations, and labor market entry co...Read more...

Blog

Politics and Policy:

Smarter, not more regulation will lead to better work

A long tradition in economics says that if an employer and a worker agree a contract on any terms both parties must be made better-off or otherwise they would not have agreed to the contract in the first place. If that w...Read more...

Journal article

Econometrica:

A Comment on: "Walras-Bowley Lecture: Market Power and Wage Inequality" by Shubhdeep Deb, Jan Eeckhout, Aseem Patel, and Lawrence Warren

A burgeoning literature in labor economics is focused on modeling employer labor market power, generally finding nontrivial estimates of monopsony power. A smaller literature also simultaneously incorporates product mark...Read more...

CEP discussion paper

Mark-ups in the digital era

Relying on a novel dataset which combines balance sheet data on firms, patents, and industry-level proxies of technology for 25 countries in the period 2001-2014, we document an increase in mark-ups over time, mainly dri...Read more...

Journal article

The Journal of Law, Economics, and Organization:

Noncompete agreements in a rigid labor market: the case of Italy

Noncompete agreements limiting the mobility of workers have been found to be widespread in the United States, a flexible and lightly regulated labor market. We explore the use of noncompete agreements in a rigid and high...Read more...

CEP discussion paper

Why delay? Understanding the construction lag, aka the build out rate

We explore the determinants of the speed of residential development after dwelling construction starts. Using a sample of over 140,000 residential developments in England from 1996 to 2015 and employing an instrumental v...Read more...

Blog

LSE Business Review:

Why representation matters in the economics profession

What prompts someone to become an economist? How important is representation in inspiring the next generation of black economists? And how positive should women economists be about the future? Felicia Odamtten, an econom...Read more...

CentrePiece article

Gender gaps from labour market downturns

How quickly do men and women find work after mass lay-offs due to workplace closures? Research by Ria Ivandic and Anne Sophie Lassen reveals that women face a greater risk of unemployment than men and lose a larger share...Read more...

Journal article

Journal of Labor Economics: Forthcoming

Technological Change and Domestic Outsourcing

Domestic outsourcing has grown substantially in developed countries over the past two decades. This paper addresses the question of the technological drivers of this phenomenon by studying the impact of the staggered dif...Read more...

Journal article

The Econometrics Journal:

Design-based identification with formula instruments: A review

Many studies in economics use instruments or treatments that combine a set of exogenous shocks with other predetermined variables via a known formula. Examples include shift-share instruments and measures of social or sp...Read more...

Chapter

Income inequality before, during, and after the transition in central and eastern Europe

in The Oxford Handbook of Post-Socialist Economies

This chapter explores the income inequality in Central and Eastern Europe before, during, and after the transition. It argues that the fall of communism and the transition to a market economy in Eastern Europe were landm...Read more...

CEP discussion paper

The social footprint of globalization: Towards the introduction of strategic industries in quantitative trade models

We argue that our understanding of industrial policy in the presence of 'strategic' industries that exert positive externalities on the national economy may benefit from an extension of quantitative general equilibrium t...Read more...

Journal article

Spatial Economic Analysis: Forthcoming

The social footprint of globalisation: towards the introduction of strategic industries in quantitative trade models

We argue that our understanding of industrial policy in the presence of ‘strategic’ industries that exert positive externalities on the national economy may benefit from an extension of quantitative general equilibrium t...Read more...

CEP discussion paper

Tickets to the global market: First US patent awards and Chinese firm exports

We investigate how international patent activity enables firms from emerging economies to thrive in the global marketplace. We match Chinese customs data to US patent records and leverage the quasi-random assignment of U...Read more...

CEP discussion paper

Adapting or compounding? The effects of recurring labour shocks on stated and revealed preferences for redistribution

The evidence on the impact of employment shocks on preferences for redistribution is mixed on stated outcomes and sparse on revealed ones. We conduct a survey of US workers to measure the impact of repeated labour market...Read more...

Journal article

American Economic Review :

The Impact of Regulation on Innovation

We present a framework that can be used to assess the equilibrium impact of regulation on endogenous innovation with heterogeneous firms. We implement this model using French firm-level panel data, where there is a sharp...Read more...

CEP discussion paper

Individual welfare analysis: A tale of consumption, time use and preference heterogeneity

How accurately does household income reflect the well-being of the individuals living within the household? Looking at household income does not take unequal consumption sharing within families, the value of time use (le...Read more...

CEP discussion paper

Do larger firms exert more market power? Markups and markdowns along the size distribution

Several models posit a positive cross-sectional correlation between markups and firm size, which characterizes misallocation, factor shares, and gains from trade. Accounting for labor market power in markup estimation, w...Read more...

Blog

Economics Observatory:

What explains the gender division of labour and how can it be redressed?

Adam Smith's division of labour was about the efficiency gains from task specialisation in factories. But the gender division - gaps between men and women in pay, prestige, career progression and much more - can also be ...Read more...

Journal article

Comparative Economic Studies:

Political connections, business groups and innovation in Asia

It is acknowledged that Asia’s remarkable economic achievements of the past 50 years build on institutional arrangements very different from the West, including the central role of business groups (BGs) as an organisatio...Read more...

Journal article

The Economic Journal:

Unraveling firms: demand, productivity and markups heterogeneity

We develop a novel framework that simultaneously allows recovering heterogeneity in demand, quantity TFP and markups across firms while leaving the correlation between the three dimensions unrestricted. We accomplish thi...Read more...

Blog

LSE Business Review:

More education signals ability to employers, but does it really improve skills?

Better educated workers may earn higher wages for two possible reasons: because they acquire more skills or because more education signals their intellect and enthusiasm. Economists believe that signalling plays a role a...Read more...

Blog

LSE Impact of Social Sciences:

New approaches to economics research are reshaping how we understand and respond to gender stereotypes

New ways of analysing data from images and text are being used by economists to study discrimination in the labour market. A recent workshop, hosted by the Centre for Economic Performance and the Department of Social Pol...Read more...

Journal article

Journal of Management Studies: Forthcoming

Business Groups and Export Performance: The Role of Coordination Failures and Institutional Configurations

We explore the nature of business groups (BGs) and their affiliates in emerging markets through the lens of the coordination failures associated with economic development. We propose that BGs develop distinct economic an...Read more...

CEP discussion paper

The measure of monopsony: the labour supply elasticity to the firm and its constituents

The estimation of labour supply elasticities is central to the measurement of monopsony power in the labor market. In this paper I provide new, firm-level estimates of the labour supply elasticity that distinguish betwee...Read more...

CentrePiece article

Superstar firms: how the shift from manufacturing to services affects local concentration of sales and jobs

The leading US firms in many industries have increased their national market share substantially over the last four decades - making these industries more concentrated. But locally the picture is more complex. David Auto...Read more...

CEP discussion paper

VAT pass-through and competition: evidence from the Greek Islands

We examine how competition affects VAT pass-through in isolated oligopolistic markets as defined by the Greek islands. Using daily gasoline prices and a difference-in-differences methodology, we investigate how changes i...Read more...

Journal article

Journal of International Economics:

Sequentially exporting products across countries

Exploiting disaggregated data on French exporters, we show that firms expand their product scope and geographical presence sequentially. This process of internationalization is uneven over time, exhibiting more volatilit...Read more...

CEP discussion paper

Non-compete agreements in a rigid labour market: the case of Italy

Non-compete clauses (NCCs) limiting the mobility of workers have been found to be rather widespread in the US, a flexible labour market with large turnover rates and a limited coverage of collective bargaining. This pape...Read more...

CentrePiece article

The paradox of vocational education

Despite a UK labour market that is hungry for skills, academic education has triumphed over training, apprenticeships and preparation for specific occupations. Alison Wolf looks at why vocational education continues to l...Read more...

CentrePiece article

Commute and thrive

The advent of commuting in 1930s London opened up opportunities to working-class people. Andrew Seltzer and Jonathan Wadsworth show how public transport boosts the labour market....Read more...

Blog

LSE Business Review:

Self-employment dwindles amid the cost-of-living crisis

As the Covid-19 crisis has made way for inflation and skyrocketing energy prices, the self-employed have not yet found their way out of the recent economic adversities. And many of them are now finding their way out of s...Read more...

CEP discussion paper

Multinationals, robots and the labor share

Using a panel of Spanish manufacturing firms covering the 1990-2017 period, this paper shows that firms acquired by multinational enterprises experience a reduction in the labor share. Acquisitions drive significant chan...Read more...

CEP discussion paper

The indirect effect of the Russian-Ukrainian war through international linkages: early evidence from the stock market

This paper investigates how firms' international linkages to Russia and Ukraine affected investors' expectations following the escalation of the Russian-Ukrainian war. For this, we perform an event study around the Russi...Read more...

Blog

Vox EU:

The labour market in Ukraine: Rebuild better

Rebuilding Ukraine will require emergency measures that address the effects of war alongside structural reforms that address pre-existing political and economic issues. Giacomo Anastasia, Tito Boeri, Marianna Kudlyak and...Read more...

Journal article

The Quarterly Journal of Economics:

Globalization, Trade Imbalances, and Labor Market Adjustment

We argue that modeling trade imbalances is crucial for understanding transitional dynamics in response to globalization shocks. We build and estimate a general equilibrium, multicountry, multisector model of trade with t...Read more...

Journal article

Regional Science and Urban Economics :

Micro-geographic property price and rent indices

We develop a programming algorithm that predicts a balanced-panel mix-adjusted house price index for arbitrary spatial units from repeated cross-sections of geocoded micro data. The algorithm combines parametric and non-...Read more...

CEP discussion paper

The spillover effect of services offshoring on local labour markets

I provide new empirical evidence on the direct and indirect impact of services off-shoring on local employment and wages, using a unique dataset on firms in the UK for the period 2000-2015. Exploiting variation in firms'...Read more...

Journal article

Ecological Economics:

The environmental cost of the international job market for economists

We provide an estimate of the environmental impact of the recruitment system in the economics profession, known as the "international job market for economists". Each year, most graduating PhDs seeking jobs in academia, ...Read more...

CentrePiece article

Environmental costs of the global job market for economists

Each year, the international job market for economists involves more than 1,000 candidates and several hundred recruiters from around the world meeting for short pre-screening interviews at annual congresses in Europe an...Read more...

Journal article

American Economic Journal: Applied Economics :

Competition and pass-through: evidence from isolated markets

We measure how pass-through varies with competition in isolated oligopolistic markets with captive consumers. Using daily pricing data from gas stations on small Greek islands, we study how unanticipated and exogenous ch...Read more...

Journal article

Labour Economics:

The gender reveal: the effect of sons on young fathers' criminal behavior and labor market activities

Based on New Zealand's administrative court charges data, we document child gender-specific differences in future criminal behavior of young fathers. The deterrent impact of having a son on the future likelihood of recei...Read more...

CEP discussion paper

Acquisitions, management and efficiency in Rwanda's coffee industry

Well-functioning markets allocate assets to owners that improve firms' management and performance. We study the effects of ownership changes on coffee mills in Rwanda - an industry in which managing relationships with fa...Read more...

CEP discussion paper

Market size, markups and international price dispersion in the cement industry

Prices for several intermediate inputs, including cement, are higher in developing economies - particularly in Africa. Combining data from the International Comparison Program with a global directory of cement plants we ...Read more...

Journal article

Economica:

Information provision and postgraduate studies

This is the first paper to examine experimentally effects of information provision on beliefs about pecuniary and non-pecuniary returns of postgraduate education, enrolment intentions and realized enrolment. We find that...Read more...

Blog

LSE Business Review:

Low pay and insecurity in the UK labour market

Minimum wage increases have driven down the incidence of low hourly pay, but there has been much less progress elsewhere for low earners. Low pay is widespread among the self-employed, who do not benefit from the minimum...Read more...

CEP discussion paper

Foreign ownership and robot adoption

This paper shows that multinational enterprises (MNEs) spur the adoption of industrial robots. First, I document a positive and robust correlation between multinational production and robot adoption using a new cross-cou...Read more...

Journal article

Economics of Education Review:

Deregulating teacher labor markets

This paper examines how the removal of national pay scales, a common feature of public sector labor markets, affects productivity. We exploit a reform that compelled all schools in England to replace pay scales with scho...Read more...

Blog

The Sutton Trust:

Gloomy prospects for social mobility in the pandemic era

Lee Elliot Major and Andrew Eyles explain how a gap in missed education between richer and poorer children was exacerbated by stark home learning divides and the likely consequences for social mobility....Read more...

External publication

Social mobility: past, present and future

Andrew Eyles, Lee Elliot Major and Stephen Machin forecast that relative income mobility levels in the UK could fall by as much as 12%, driven by learning loss in schools....Read more...

CEP discussion paper

Managing export complexity: The role of service outsourcing

As manufacturing firms expand globally, business services like advertising and legal support become essential for accessing new markets. This paper investigates how firms organize the provision of such market access serv...Read more...

Journal article

Labour Economics:

Slack and prices during Covid-19: accounting for labor market participation

Strong labor force participation cyclicality during the Covid-19 pandemic has put further into question the capacity of standard Phillips Curve (PC) models to fully capture labor market cyclical conditions. In this paper...Read more...

Journal article

Oxford Economic Papers:

Economic geography aspects of the Panama Canal

This paper studies how the opening of the Panama Canal in 1914 changed counties’ market potential and influenced the economic geography of the USA. We compute shipment effective distances with and without the canal from ...Read more...

Journal article

Management Science: Forthcoming

Vertical integration and foreclosure: evidence from production network data

This paper studies the prevalence of potential anticompetitive effects of vertical mergers using a novel data set on U.S. and international buyer-seller relationships and across a large range of industries. We find that ...Read more...

External publication

Monopsony in local labour markets

In this commentary, we propose a monopsony model of the labour market in which market power stems from idiosyncratic worker preferences over non-wage attributes of jobs. In this set-up, the relationship between wages and...Read more...

External publication

Labour market inequality

Wage and earnings inequality has been on the rise in the UK since the late 1970s / early 1980s, and with faster increases than comparator countries it is now one of the countries with the highest levels of wage and earni...Read more...

Journal article

Journal of International Economics:

Technology, market structure and the gains from trade

We study the gains from trade in a model with oligopolistic competition, heterogeneous firms and innovation. Our key finding is that a trade-induced increase in market concentration can be an important source of the gain...Read more...

Blog

VoxEU:

Inflation, market power, and price controls: views of leading economists

With sharply rising US inflation prompting debate about the potential role of powerful firms in driving up prices and whether antitrust interventions and/or price controls may be an effective policy response, the IGM For...Read more...

Blog

VoxEU:

Working from home and corporate real estate

As remote working became more common during Covid-19, Antonin Bergeaud, Jean Benoit Eymeoud, Thomas Garcia and Dorian Henricot examine how corporate real-estate market participants adjusted to the growth of teleworking i...Read more...

Blog

VoxEU:

The environmental burden of the international job market for economists

Each year, the 'international job market for economists' involves over 1,000 junior candidates and several hundred recruiters from all over the world meeting for short pre-screening interviews at annual congresses in Eur...Read more...

Blog

VoxEU:

The value of online gig economy platforms

The gig economy and online labour platforms often trade off increased flexibility for lower employment security. Christopher Stanton and Catherine Thomas show how traditional labour market regulations, such as minimum wa...Read more...

External publication

Changing jobs?

This report is about the nature and speed of change in the UK's labour market, about how past periods of rapid change have happened, and about workers' experiences as they have lived through these changes. It is written ...Read more...

CEP discussion paper

The environmental cost of the international job market for economists

We provide an estimate of the environmental impact of the recruitment system in the economics profession, known as the "international job market for economists". Each year, most graduating PhDs seeking jobs in academia, ...Read more...

Journal article

Journal of Participation and Employee Ownership:

Footsie,Yeah! Share Prices and Worker Wellbeing

A small literature has shown that individual wellbeing varies with the price of company stock, but it is unclear whether this is due to wealth effects amongst those holding stock, or more general effects on sentiment, wi...Read more...

Journal article

Management Science:

Building a Productive Workforce: The Role of Structured Management Practices

In an influential study, Bender et al. [Bender S, Bloom N, Card D, Van Reenen J, Wolter S (2018) Management practices, workforce selection, and productivity. J. Labor Econom. 36(S1):S371-S409] document consistent relatio...Read more...

Journal article

Journal of the European Economic Association:

Marshall Lecture 2020 The Measure of Monopsony

There has been increasing interest in recent years in monopsony in the labour market. This paper discusses how we can measure monopsony power by combining insights from models based on both frictions and idiosyncrasies. ...Read more...

CEP discussion paper

Population growth, immigration and labour market dynamics

This paper examines the role of population flows on labour market dynamics across immigrant and native-born populations in the United Kingdom. Population flows are large, and cyclical, driven first by the maturation of b...Read more...

CEP discussion paper

Have productivity and pay decoupled in the UK?

In the long-run at the macro level, the real pay of workers tends to follow labour productivity. In recent years, however, there have been concerns that this relationship has broken down and that pay has become "decouple...Read more...

CEP discussion paper

Minimum wages and the China syndrome: causal evidence from US local labor markets

Exposure to Chinese import competition led to significant manufacturing job losses in the United States. Local labor markets, however, differ significantly in how they fared with respect to manufacturing employment. An i...Read more...

Journal article

International Journal of Manpower:

Eastern European immigrants in the UK

The paper aims at examining wage developments among Eastern European immigrants vs UK natives before and after the 2004 enlargement by measuring the extent to which inter-group wage differentials are explainable by these...Read more...