Results

Journal article

Journal of Environmental Economics and Management:

Air pollution and innovation

If air pollution harms innovation - and therefore future productivity - existing assessments of its economic cost are incomplete. We estimate the effect of fine particulate matter concentration on inventive output in 977...Read more...

Blog

LSE Euro PP:

A new measure of quality of life explains why people like living in bigger cities

People like to live in certain places, even when higher wages are on offer elsewhere. Gabriel Ahlfeldt, Fabian Bald, Duncan Roth and Tobias Seidel show that once you take into account people's preferences, large cities o...Read more...

Chapter

WELLBY

in Elgar Encyclopedia of Behavioural and Experimental Economics

The WELLBY is a measure of individual subjective wellbeing, as judged by individuals themselves, capturing both the quality of life and the length of life. We outline its use for measuring social progress and for social ...Read more...

Journal article

Research Policy:

Who stands on the shoulders of Chinese (Scientific) Giants? Evidence from chemistry

China’s rise in science has the potential to push forward the knowledge frontier, but mere production of knowledge does not guarantee that others are able to build on it. We ask whether chemistry research originating fro...Read more...

CEP discussion paper

Measuring quality of life under spatial frictions

Using a quantitative spatial model as a data-generating process, we explore how spatial frictions affect the measurement of quality of life. We find that under a canonical parameterization, mobility frictions - generated...Read more...

Journal article

Journal of Economic Geography:

On the productivity advantage of cities

Agglomeration externalities are the key factor explaining the existence of cities and their size. However, while the various micro foundations of agglomeration externalities stress the importance of total factor producti...Read more...

Journal article

Review of World Economics:

Curse or blessing? multinational corporations and labor market outcomes in Africa

Do multinational enterprises create local job opportunities in developing countries? We address this question in the context of Sub-Saharan Africa by combining information on domestic and foreign multinationals’ affiliat...Read more...

Journal article

Journal of International Economics: Forthcoming

Accounting for trade patterns

We develop a quantitative framework for decomposing trade patterns. We derive price indexes that determine comparative advantage and the aggregate cost of living. If firms and products are imperfect substitutes, we show ...Read more...

CEP discussion paper

Trade, skills and productivity

We examine how firms adjust their production and technology in response to exogenous trade shocks. We develop a model in which revenue TFP can be distinguished from quantity TFP, and where skill upgrading is explicitly e...Read more...

Journal article

Economica:

Do wages underestimate the inequality in workers' rewards? The joint distribution of job quality and wages across occupations

Information on both wages and job quality is needed in order to understand the occupational dispersion of wellbeing. We analyse subjective wellbeing in a large UK sample to construct a measure of ‘overall reward’, the su...Read more...

Chapter

Women's representation and the gender pay gap: rank, institutional research intensity and ethnicity in UK business schools

in Research Handbook on Inequalities and Work

We employ a multi-faceted framework to explore the importance of women's representation to the gender pay gap (GPG) in all UK business schools to analyse an authoritative and complete administrative sample from the Highe...Read more...

CEP discussion paper

Firms in product space: Adoption, growth and competition

Which products are potentially produced together? When demand for a product increases, which firms will supply it? Using multi-product production patterns within and across firms, we recover a continuous cost based dista...Read more...

CEP discussion paper

Rethinking revealed comparative advantage with micro and macro data

The Balassa's index of revealed comparative advantage does not necessarily reveal Ricardian comparative advantage. We propose an alternative sufficient statistics approach based on a quantitative standard trade model inc...Read more...

CEP discussion paper

Has financial fair play changed European football?

In 2011 UEFA, the governing body of European football, introduced the Financial Fair Play Regulation (FFPR), consisting of a set of financial restraints to be met by clubs as a prerequisite for participation to its compe...Read more...

Journal article

Management Science:

Information Spillovers in Experience Goods Competition

Trialing an experience good allows consumers to learn their value for the sampled good and also informs beliefs about their value for similar products. These demand-side information spillovers across products create a re...Read more...

CEP discussion paper

Who stands on the shoulders of Chinese (scientific) giants? Evidence from chemistry

China's rise in science has the potential to push forward the knowledge frontier, but mere production of knowledge does not guarantee that others are able to build on it. We ask whether chemistry research originating fro...Read more...

Journal article

Journal of Political Economy: Forthcoming

The comparative advantage of firms

Resource-based theories propose that firms grow by diversifying into products that use common capabilities. We provide evidence for common-input capabilities, using a policy that removed entry barriers in input markets t...Read more...

Journal article

Nature Communications: Forthcoming

The effect of Covid certificates on vaccine uptake, health outcomes, and the economy

In the COVID-19 pandemic many countries required COVID certificates, proving vaccination, recovery, or a recent negative test, to access public and private venues. We estimate their effect on vaccine uptake for France, G...Read more...

Journal article

Social Science and Medicine: Forthcoming

"Better the devil you know": Are stated preferences over health and happiness determined by how healthy and happy people are?

Most people want to be both happy and healthy. But which matters most when there is a trade-off between them? This paper addresses this question by asking 4000 members of the UK and US public to make various choices betw...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...

CEP discussion paper

Air pollution and innovation

If air pollution harms innovation -- and therefore future productivity -- existing assessments of its economic cost are incomplete. We estimate the effect of fine particulate matter concentration on inventive output in 1...Read more...

Journal article

China Economic Review:

Compensating for academic loss: Online learning and student performance during the COVID-19 pandemic

The COVID-19 pandemic has led to widespread school shutdowns, with many continuing distance education via online-learning platforms. We here estimate the causal effects of online education on student exam performance usi...Read more...

CEP discussion paper

Firm export responses to tariff hikes

We study how firms react to unexpected increases in import tariffs. We identify our results from a sudden removal of American preferential tariffs applied on Argentine imports under the Generalized System of Preferences,...Read more...

Journal article

Journal of Economic Behavior and Organization:

Job quality and workplace gender diversity in Europe

We here consider the relationship between workplace gender measures and employees’ perceived job quality, where the former cover both the gender mix of workers with the same job title and the gender of the immediate boss...Read more...

CEP discussion paper

Quality of life in a dynamic spatial model

We develop a dynamic spatial model in which heterogeneous workers are imperfectly mobile and forward-looking and yet all structural fundamentals can be inverted without assuming that the economy is in a stationary spatia...Read more...

Journal article

Early Childhood Research Quarterly:

The when and what of measuring ECE quality: Analysis of variation in the Classroom Assessment Scoring System (CLASS) across the ECE day

Observational assessment has become an integral component of the quality improvement agenda in Early Care and Education (ECE) and has been significant in directing attention to quality of interactions within the ECE sett...Read more...

Journal article

Review of Industrial Organization:

The Gravity of Intermediate Goods

One of the puzzles of the gravity literature is the persistent effect of distance on trade flows, despite the dramatic fall in trade costs during the last few decades (Disdier and Head in Rev Econ Stat 90(1):37–48, 2008)...Read more...

CEP discussion paper

Managing global production: theory and evidence from just-in-time supply chains

Global value chains are highly fragmented across countries and dominated by a few large multinational firms. But the challenges of an increasingly difficult international business environment are raising the question of ...Read more...

CEP discussion paper

On the productivity advantage of cities

Ever since Marshall (1890) agglomeration externalities have been viewed as the key factor explaining the existence of cities and their size. However, while the various micro foundations of agglomeration externalities str...Read more...

CEP discussion paper

Environmental preferences and technological choices: is market competition clean or dirty?

We investigate the effects of consumers' environmental concerns and market competition on firms' decisions to innovate in 'clean' technologies. Agents care about their consumption and environmental footprint; firms pursu...Read more...

Journal article

Quarterly Journal of Economics:

Measuring Aggregate Price Indices with Taste Shocks: Theory and Evidence for CES Preferences

We develop an approach to measuring the cost of living for CES preferences that treats demand shocks as taste shocks that are equivalent to price shocks. In the presence of relative taste shocks, the Sato-Vartia price in...Read more...

CEP discussion paper

Intellectual property and the organization of the global value chain

This paper introduces the concept of intangible assets in a property rights model of sequential supply chains. Firms transmit knowledge to their suppliers to facilitate input customization. Yet, to avoid knowledge dissip...Read more...

CEP discussion paper

Vertical integration and foreclosure: evidence from production network data

This paper studies the prevalence of vertical market foreclosure using a novel dataset on U.S. and international buyer-seller relationships, and across a large range of industries. We find that relationships are more lik...Read more...

CEP discussion paper

Widening the high school curriculum to include soft skill training: impacts on health, behaviour, emotional wellbeing and occupational aspirations

From 2020 the health and relationships aspects of Personal, Social, Health and Economic Education will be compulsory in UK schools for adolescents. However less is known about how it can be taught in an effective manner....Read more...

Journal article

The Quarterly Journal of Economics:

The unequal gains from product innovations: Evidence from the U.S. Retail sector

This article examines how product innovations led to inflation inequality in the United States from 2004 to 2015. Using scanner data from the retail sector, I find that annual inflation for retail products was 0.661 (std...Read more...

CEP discussion paper

The comparative advantage of firms

Resource based theories propose that firms grow by diversifying into products which use common capabilities. We provide evidence for common input capabilities using a policy that removed entry barriers in input markets t...Read more...

Journal article

SSM - Population Health:

Crime victimisation over time and sleep quality

We here consider the relationship between the individual time profile of crime victimisation and sleep quality. Sleep quality worsens with contemporaneous crime victimisation, with physical violence having a larger effec...Read more...

Journal article

Review of Economic Studies:

Carry-along trade

Large multi-product firms dominate international trade flows. This paper documents new facts about multi-product manufacturing exporters that are not easily reconciled with existing multi-product models. Using novel link...Read more...

Journal article

Journal of Political Economy:

Monopolistic competition and optimum product diversity under firm heterogeneity

Empirical work has drawn attention to the high degree of productivity differences within industries and their role in resource allocation. This paper examines the allocational efficiency of such markets. Productivity dif...Read more...

CEP discussion paper

Organizing global supply chains: input-output linkages and vertical integration

We study whether and how the technological importance of an input – measured by its cost share – is related to the decision of whether to “make” or “buy” that input. Using detailed French international trade data and an ...Read more...

CEP discussion paper

Managing trade: evidence from China and the US

We study how management practices shape export performance using matched production-trade-management data for Chinese and American firms and a randomized control trial in India. Better managed firms are more likely to ex...Read more...

Journal article

Journal of Economic Literature:

Global firms

Research in international trade has changed dramatically over the last twenty years, as attention has shifted from countries and industries towards the firms actually engaged in international trade. The now-standard hete...Read more...

CentrePiece article

Nursery attendance and children's outcomes

The UK government has expanded the popular ‘free entitlement’ to part-time early education and care from a universal 15 hours per week to 30 hours per week for working parents. But research by Jo Blanden and co-authors r...Read more...

Journal article

Research in Economics:

Monopolistic competition and optimum product selection: Why and how heterogeneity matters

After some decades of relative oblivion, the interest in the optimality properties of monopolistic competition has recently re-emerged due to the availability of an appropriate and parsimonious framework to deal with fir...Read more...

CEP discussion paper

Aggregating from micro to macro patterns of trade

We develop a new framework for aggregating from micro to macro patterns of trade. We derive price indexes that determine comparative advantage across countries and sectors and the aggregate cost of living. If firms and p...Read more...

CEP discussion paper

Product diversification in Indian manufacturing

The presence of global value chains challenges the neoclassical idea of the firm since it implies firms are not monolithic but are rather interdependent on the larger economic environment. Examining establishments, the s...Read more...

CEP discussion paper

The hospital as a multi-product firm: the effect of hospital competition on value-added indicators of clinical quality

There is increasing international interest in using Patient Reported Outcome Measures (PROMs) to assess health care provider performance. PROMs are a fundamental advance on existing indicators of health care quality in t...Read more...

CEP discussion paper

Teacher quality, test scores and non-cognitive skills: evidence from primary school teachers in the UK

Schooling can produce both cognitive and non-cognitive skills, both of which are important determinants of adult outcomes. Using very rich data from a UK birth cohort study, I estimate teacher value added (VA) models for...Read more...

CEP discussion paper

Multi-product firms and product quality

We examine the global operations of multi-product firms. We present a flexible heterogeneous-firm trade model with either limited or strong scope for quality differentiation. Using customs data for China during 2002-2006...Read more...

CEP discussion paper

Quality in early years settings and children’s school achievement

Childcare quality is often thought to be important for influencing children’s subsequent attainment at school. The English Government regulates the quality of early education by setting minimum levels of qualifications f...Read more...

Journal article

Journal of International Economics:

Multi-product firms and product quality

We examine the global operations of multi-product firms. We present a flexible heterogeneous-firm trade model with either limited or strong scope for quality differentiation. Using customs data for China during 2002–2006...Read more...

CEP discussion paper

Product switching and the business cycle

This paper explores role of product adding and dropping within manufacturing firms over the business cycle. While a substantial body of work has explored the importance of the extensive margins of firm entry and exit in ...Read more...

CEP discussion paper

Global firms

Research in international trade has changed dramatically over the last twenty years, as attention has shifted from countries and industries towards the firms actually engaged in international trade. The now-standard hete...Read more...

CEP discussion paper

Swimming upstream: input-output linkages and the direction of product adoption

Multiproduct firms dominate production, and their product turnover contributes substantially to aggregate growth. Firms continually adapt their product mix, but what determines which products firms expand into? Theories ...Read more...

Journal article

The Scandinavian Journal of Economics:

Valuing School Quality via a School Choice Reform

Among policymakers, educators, and economists, there remains a strong debate on the extent to which good schools matter. In this paper, we estimate school quality valuations based upon house prices, by considering a poli...Read more...

Journal article

The Economic Journal:

Income and Population Growth

Do populations grow as countries become richer? In this study we estimate the effects on population growth of shocks to national income that are plausibly exogenous and unlikely to be driven by technological change. For ...Read more...

CEP discussion paper

Contracting and the division of the gains from trade

This paper examines the microstructure of import markets and the division of the gains from trade among consumers, importers and exporters. When exporters and importers transact through anonymous markets, double marginal...Read more...

Journal article

The Review of Economics and Statistics:

Intermediaries in international trade: Products and destinations

This paper examines the factors that give rise to intermediaries in exporting and explores the implications for trade volumes. Export intermediaries such as wholesalers serve different markets and export different produc...Read more...

Journal article

The Economic Journal:

Are You Happy While You Work?

Using a new data source permitting individuals to record their well-being via a smartphone, we explore within-person variance in individuals’ well-being measured momentarily at random points in time. We find paid work is...Read more...

CEP discussion paper

Vertical transmission of overweight: evidence from English adoptees

We examine the vertical transmission of overweight drawing upon a sample of English children, both adopted and non-adopted, and their families. Our results suggest strong evidence of an intergenerational association of o...Read more...

CentrePiece article

Educational efficiency: value for money in public spending on schools

Which national education systems deliver the best value for money? Peter Dolton and colleagues rank 30 of the world’s richest countries based on their expenditure on teacher costs (which account for 80% of education budg...Read more...

CEP discussion paper

Benford's law, families of distributions and a test basis

Benford's Law is used to test for data irregularities. While novel, there are two weaknesses in the current methodology. First, test values used in practice are too conservative and the test values of this paper are more...Read more...

CEP discussion paper

Monopolistic Competition and Optimum Product Selection: Why and How Heterogeneity Matters

After some decades of relative oblivion, the interest in the optimality properties of monopolistic competition has recently re-emerged due to the availability of an appropriate and parsimonious framework to deal with fir...Read more...

Journal article

Journal of Urban Economics:

Valuing school quality using boundary discontinuities

Existing research shows that house prices respond to local school quality as measured by average test scores. However, higher test scores could signal higher academic value-added or higher ability, more sought-after inta...Read more...

CEP discussion paper

On the Measurement of Trade Costs: Direct vs. Indirect Approaches to Quantifying Standards and Technical Regulations

In this article, we review the literature on the measurement of trade costs in international trade with a special emphasis on nontariff measures and in particular on standards and technical regulations. We distinguish ‘d...Read more...

CEP discussion paper

Human Capital, Matching and Job Satisfaction

Using a model of wage determination developed by Stevens (2003) we offer an explanation of why tenure has a negative effect when entered in job satisfaction equations. If job satisfaction measures match quality, then the...Read more...

CEP discussion paper

Market Size, Competition, and the Product Mix of Exporters

We build a theoretical model of multi-product firms that highlights how competition across market destinations affects both a firm's exported product range and product mix. We show how tougher competition in an export ma...Read more...

CEP discussion paper

Intermediaries in International Trade: Direct Versus Indirect Modes of Export

This paper examines the factors that give rise to intermediaries in exporting and explores the implications for trade volumes. Export intermediaries such as wholesalers serve different markets and export different produc...Read more...

CEP discussion paper

Global Value Chains During the Great Trade Collapse: A Bullwhip Effect?

This paper analyzes the performance of global value chains during the trade collapse. To do so, it exploits a unique transaction-level dataset on French firms containing information on cross-border monthly transactions m...Read more...

CEP discussion paper

The Determinants of Intrafirm Trade: Evidence from French Firms

How well does the theory of the firm explain the choice between intrafirm and arms' length trade? This paper uses firm-level import data from France to look into this question. We find support for three key predictions o...Read more...

CEE/Education and skills discussion paper

Valuing School Quality Using Boundary Discontinuities

Existing research shows that house prices respond to local school quality as measured by average test scores. However, higher test scores could signal better quality teaching and academic value-added, or higher ability, ...Read more...

CEP discussion paper

The Role of Educational Quality and Quantity in the Process of Economic Development

We develop a theory of human capital investment to study the channels through which students react to school quality when deciding on investments in secondary education and above, and to study how educational quality aff...Read more...

CEP occasional paper

Houses and schools: valuation of school quality through then housing market - EALE 2010 presidential address

This paper offers a critical appraisal of the now sizable empirical literature that values school quality and performance through housing valuations. This literature consistently finds housing valuations to be significan...Read more...

CEP discussion paper

The Spatial Organization of Multinational Firms

Using six years of firm-level data covering 224 regions of the enlarged European Union, we evaluate the importance to a firm of locating its activities (production, headquarters, R&D, logistics and sales) close together....Read more...

CEP discussion paper

A Task-Based Approach to Organization: Knowledge, Communication and Structure

We bridge a gap between organizational economics and strategy research by developing a task-based approach to analyze organizational knowledge, process and structure, and deriving testable implications for the relation b...Read more...

CEP discussion paper

Trade as an Engine of Creative Destruction: Mexican Experience with Chinese Competition

This paper exploits the surge in Chinese exports from 1994 to 2004 as a natural experiment to evaluate the effects of a unilateral low wage trade and competition shock to producers in Mexico. We find that this shock caus...Read more...

CEP discussion paper

Quality Matters - the Expulsion of Professors and Ph.D. Student Outcomes in Nazi Germany

I investigate the effect of faculty quality on Ph.D. student outcomes. To address the endogeneity of faculty quality I use exogenous variation provided by the expulsion of mathematics professors in Nazi Germany. I find t...Read more...

CEP discussion paper

The Determinants of Vertical Integration in Export Processing: Theory and Evidence from China

Using detailed product-level export data for China and a variant of the Antràs and Helpman (2004) model that includes investments in component search, we examine the sectoral determinants of foreign direct investment (FD...Read more...

Journal article

Journal of Political Economy:

Can pay regulation kill? Panel data evidence on the effect of labor markets on hospital performance

In many sectors, pay is regulated to be equal across heterogeneous geographical labor markets. When the competitive outside wage is higher than the regulated wage, there are likely to be falls in quality. We exploit pane...Read more...

SERC/Urban and Spatial Programme Discussion Paper

Does Hospital Competition Save Lives? Evidence from the English NHS Patient Choice Reforms

This paper examines whether or not hospital competition in a market with fixed reimbursement prices can prompt improvements in clinical quality. In January 2006, the British Government introduced a major extension of the...Read more...

SERC/Urban and Spatial Programme Discussion Paper

Valuing School Quality Using Boundary Discontinuities

A large body of international research shows that house prices respond to local school quality as measured by average test scores. But better test scores could signal better expected academic outputs or simply reflect hi...Read more...

CEE/Education and skills discussion paper

University Quality and Graduate Wages in the UK

We examine the links between various measures of university quality and graduate earnings in the United Kingdom. We explore the implications of using different measures of quality and combining them into an aggregate mea...Read more...

CEE/Education and skills discussion paper

School Quality, Child Wellbeing and Parents Satisfaction

Researchers in economics of education usually assume that parents choose schools for their high academic performance, with some support from revealed preference evidence based on local house prices. However, anecdotal ev...Read more...

CEP discussion paper

The Margins of US Trade

Recent research in international trade emphasizes the importance of firms’ extensive margins for understanding overall patterns of trade as well as how firms respond to specific events such as trade liberalization. In th...Read more...

CEP discussion paper

Product Market Deregulation and the U.S. Employment Miracle

We consider the dynamic relationship between product market entry regulation and equilibrium unemployment. The main theoretical contribution is combining a job matching model with monopolistic competition in the goods ma...Read more...

CEP discussion paper

International Trade, Minimum Quality Standards and the Prisoners' Dilemma

Unilateral minimum quality standards are endogenously determined as the outcome of a non-cooperative standard-setting game between the governments of two countries. Cross-country externalities from the implementation of ...Read more...

CEP discussion paper

Can Pay Regulation Kill? Panel Data Evidence on the Effect of Labor Markets on Hospital Performance

Labor market regulation can have harmful unintended consequences. In many markets, especially for public sector workers, pay is regulated to be the same for individuals across heterogeneous geographical labor markets. We...Read more...

CEP discussion paper

Intra-Industry Foreign Direct Investment

We use a new firm level data set that establishes the location, ownership, and activity of 650,000 multinational subsidiaries—close to a comprehensive picture of global multinational activity. A number of patterns emerge...Read more...

CEP discussion paper

Multi-Product Firms and Trade Liberalization

This paper develops a general equilibrium model of multi-product firms and analyzes their behavior during trade liberalization. Firm productivity in a given product is modeled as a combination of firm-level “ability” and...Read more...

CEP discussion paper

Multi-Product Firms and Product Switching

This paper examines the frequency, pervasiveness and determinants of product switching among U.S. manufacturing firms. We find that two-thirds of firms alter their mix of five-digit SIC products every five years, that on...Read more...

CEP discussion paper

Products and Productivity

Firms' decisions about which goods to produce are often made at a more disaggregate level than the data observed by empirical researchers. When products differ according to production technique or the way in which they e...Read more...

CEP discussion paper

How Does Product Market Competition Shape Incentive Contracts?

This paper studies the effect of product market competition on the explicit compensation packages that firms offer to their CEOs, executives and workers. We use a large sample of both traded and non-traded UK firms and e...Read more...

CEP discussion paper

Product Market Competition Returns to Skill and Wage Inequality

This paper shows that increasing product market competition can have a direct impact on the employment relationship and on wage inequality. I develop a simple model in which an increase in product market competition incr...Read more...

CEP discussion paper

Executive Compensation and Product Market Competition

The aim of this paper is to study the effects of product market competition on the explicit compensation packages that firms offer to their executives. In order to measure the net effect of competition we use two differe...Read more...

CEP discussion paper

Product Choice and Product Switching

This paper develops a model of endogenous product selection by firms. The theory is motivated by new evidence we present on the importance of product switching by U.S. manufacturers. Two-thirds of continuing firms change...Read more...

CEP discussion paper

City Size Distributions As A Consequence of the Growth Process

The size distribution of cities in many countries follows some broadly regular patterns. Any good theory of city size distributions should (i) be able to account for this regularity, but also (ii) rely on a plausible eco...Read more...

CEP discussion paper

Matching Demand and Supply in a Weightless Economy: Market-Driven Creativity With and Without IPRs

Many cultural products have the same nonrival nature as scientific knowledge. They therefore face identical difficulties in creation and dissemination. One traditional view says market failure is endemic: societies toler...Read more...

CEP discussion paper

Product Standards, Trade Disputes and Protectionism

Trade disputes over national product standards are a growing source of tension in the international trading system. The usual pattern is that a country introduces a new product standard for all sales of a good in its loc...Read more...

CEP discussion paper

Per Capita Income Demand for Variety, and International Trade: Linder Reconsidered

We analyse a monopolistically competitive model of international trade where goods must be consumed in indivisible amounts. The number of varieties that enter a consumer's optimal consumption bundle is increasing in the...Read more...

CEP discussion paper

The Multi-Dimensional Nature of Labour Demmand and Skill Biased Technical Change

Investigating the robustness of the skill-biased technological change hypothesis, this analysis incorporates two novel features. First, effective labor is modeled as the product of a quantity measure û number of employee...Read more...