Labour economics

In short

Labour economics studies how wages, employment and working conditions are determined by the decisions of workers (supply) and firms (demand), and how institutions — unions, minimum wages, labour codes, social security — change those outcomes. It matters in India because roughly half the workforce is still in agriculture or informal work, female participation is low, and policy debates on the four Labour Codes, rural employment-guarantee wages and skilling turn on exactly this analysis. It is examined in BA/MA Economics papers on labour and development economics, in UGC-NET and Indian Economic Service papers, and in RBI Grade B / NABARD / SEBI phase-II descriptive papers. Employers test it in roles at policy think-tanks, HR analytics, consulting and data teams that read PLFS, EPFO and NSS data.

Explained

Labour supply: the individual and the aggregate

• A worker allocates a fixed time endowment (say 24 hours) between work and leisure, maximising utility U(C, L) subject to the budget constraint C = wH + V, where w is the wage, H hours worked and V non-labour income.
• The tangency condition is MRS of leisure for consumption = real wage: the marginal rate of substitution equals w. The wage is the opportunity cost of leisure.
• A wage rise has two effects: substitution effect (leisure dearer → work more) and income effect (richer → buy more leisure → work less). Net effect is ambiguous.
• If the income effect dominates at high wages, the individual supply curve bends backwards — the classic backward-bending labour supply curve.
• Reservation wage: the lowest wage at which a person will accept work; below it, hours supplied = 0 (corner solution). It rises with non-labour income V, transfer payments and household wealth.
• Participation decision (extensive margin) versus hours decision (intensive margin). India's low female labour force participation rate (FLFPR) is largely an extensive-margin problem — unpaid domestic work, safety, social norms, and the "U-shaped" relation with education and income.
• Aggregate supply to a firm or an occupation is far more elastic than aggregate supply to the economy, because workers can switch employers.

Labour demand and wage determination

• Labour demand is derived demand — derived from demand for the output. The firm hires up to MRP_L = W (marginal revenue product = wage); in a competitive product market MRP_L = P × MP_L, so MP_L = W/P (real wage = marginal product).
• Short run: capital fixed, demand curve = declining portion of MRP_L due to diminishing marginal returns. Long run: both inputs vary; demand is flatter (more elastic) because of substitution between labour and capital.
• Hicks–Marshall laws of derived demand — labour demand is more elastic when (i) the elasticity of substitution between labour and other inputs is high, (ii) product demand is elastic, (iii) labour's share in total cost is large, (iv) supply of other inputs is elastic.
• Monopsony: a single buyer of labour faces an upward-sloping supply curve, so marginal cost of labour MC_L > W. It hires where MRP_L = MC_L, giving lower wage and lower employment than competition — a reason a modest minimum wage can raise both wage and employment. Relevant to company towns, plantations and some rural labour markets.
• Monopoly union / bilateral monopoly: a union maximising its members' welfare sets a wage above the competitive level, trading wage against employment along the demand curve.
• Theories of wages: subsistence theory (Ricardo), wages-fund theory (Mill), marginal productivity theory (Clark) and its criticisms (assumes homogeneity, perfect competition, measurability of MP_L), bargaining theory (Davidson), efficiency wage theories (shirking, turnover, adverse selection, nutrition/fair-wage — Shapiro–Stiglitz) which explain involuntary unemployment as an equilibrium.
• Compensating wage differentials: risky, dirty or remote jobs pay more, other things equal; equalising differences (Adam Smith). Differentials also arise from skill, unionisation, firm size and location.

Human capital and earnings

• Human capital is the stock of skills and health embodied in people; schooling and training are investments with costs now and returns later (Becker, Schultz, Mincer).
• Decision rule: invest if the present value of the extra earnings stream exceeds direct costs plus foregone earnings (usually the larger cost). Investment falls with age (shorter payback) and with the discount rate.
• General versus specific training: general training raises productivity anywhere, so the worker bears the cost (lower training wage); firm-specific training is cost-shared, and the firm captures part of the return — which is why specific-skilled workers are less likely to be laid off.
• Mincer earnings function: ln W = β₀ + β₁S + β₂X + β₃X² + u; β₁ is the private return to an extra year of schooling (around 5–9% per year in Indian estimates, higher for tertiary and for women; estimates vary by dataset and year). The negative X² term gives the concave age–earnings profile.
• Signalling (Spence): education may signal pre-existing ability rather than create productivity — hence the "sheepskin effect" (a jump in earnings at degree completion). Ability bias overstates OLS returns; schooling-reform and twin-study instruments are used to correct it.
• Screening, credentialism and skill mismatch matter in India, where employability surveys repeatedly find a gap between degrees held and skills demanded.

Unemployment, search and segmentation

• Types: frictional (search and matching), structural (skill or spatial mismatch), cyclical (deficient demand), seasonal (acute in Indian agriculture), disguised unemployment (surplus labour whose marginal product is near zero — Nurkse) and underemployment (visible: too few hours; invisible: low productivity/earnings).
• Measurement in India (PLFS, by NSO): Usual Status (ps+ss) uses a 365-day reference with a majority-time criterion; Current Weekly Status (CWS) uses a 7-day reference and treats one hour of work on any day as employed. CWS unemployment is typically higher than usual-status, because the short reference period picks up intermittent and seasonal joblessness. Key rates: LFPR, WPR (worker population ratio) and UR, all for age 15+ in headline reporting.
• Structure of Indian employment: self-employed (own-account workers plus unpaid helpers in household enterprises), regular wage/salaried, and casual labour. Informality is the dominant feature — the large majority of workers lack written contracts or social security; own-account and unpaid family work rose in recent PLFS rounds.
• Search theory: an unemployed worker samples wage offers and accepts any offer at or above the reservation wage; expected duration of unemployment = 1/(job-finding rate). Unemployment insurance raises the reservation wage and duration but can improve match quality. Beveridge curve plots vacancies against unemployment; outward shifts signal worse matching.
• Phillips curve and NAIRU: short-run inverse relation between unemployment and wage/price inflation; vertical in the long run at the natural rate.
• Dual/segmented labour markets: a protected formal "primary" sector and an unprotected "secondary" sector, with limited mobility between them.
• Lewis–Fei–Ranis model: surplus labour moves from subsistence agriculture to industry at a roughly constant wage until the Lewis turning point; Harris–Todaro explains rural–urban migration by *expected* urban wage (formal wage × probability of employment), so migration continues despite urban unemployment.

Institutions, discrimination and Indian labour law

• Trade unions and collective bargaining: craft, industrial, general and federations (BMS, INTUC, CITU, AITUC, HMS). Functions — wage bargaining, grievance redress, voice. Union density in India is low and concentrated in the public sector and organised manufacturing.
• Industrial disputes are settled by conciliation, voluntary arbitration and adjudication (Labour Court, Industrial Tribunal, National Tribunal); under the Industrial Relations Code, 2020 strikes and lockouts require 14 days' notice in all industrial establishments, whereas the repealed ID Act, 1947 required notice only in public utility services.
• Four Labour Codes, in force from 21 November 2025, consolidating 29 central laws:
  1. Code on Wages, 2019 — minimum wages, a statutory floor wage set by the Centre, timely payment, equal remuneration regardless of gender; subsumes the Minimum Wages Act, 1948, Payment of Wages Act, 1936, Payment of Bonus Act, 1965 and Equal Remuneration Act, 1976.
  2. Industrial Relations Code, 2020 — standing orders, trade union recognition (negotiating union/council), notice for strikes, retrenchment and closure; subsumes the Industrial Disputes Act, 1947.
  3. Code on Social Security, 2020 — EPF, ESI, gratuity, maternity benefit, and a framework for gig and platform workers with aggregator contributions.
  4. Occupational Safety, Health and Working Conditions Code, 2020 — subsumes the Factories Act, 1948, Contract Labour Act, 1970, Inter-State Migrant Workmen Act, 1979 and the BOCW Act, 1996.
• Minimum wage theory: in a competitive market a binding minimum wage above equilibrium creates excess supply (unemployment plus queuing); in monopsony or with efficiency wages it can raise employment. Empirical evidence worldwide is mixed; in India weak enforcement and informality blunt its bite.
• Wage components in Indian practice: basic wage, dearness allowance (DA, indexed to CPI-IW), HRA and allowances. The Codes define "wages" with a rule that excluded allowances cannot exceed 50% of total remuneration — raising PF and gratuity bases.
• Discrimination: taste-based (Becker), statistical discrimination (group averages used as a proxy for individual productivity), crowding/occupational segregation, and caste- and gender-based differentials documented in Indian wage decompositions (Oaxaca–Blinder). Constitutional and statutory backing: Articles 14, 15, 16, 23, 39(d) and 43; equal remuneration now inside the Code on Wages.
• Active labour market policy in India: the rural employment guarantee — MGNREGA (100 days of guaranteed unskilled manual work per rural household, 2005) was repealed and replaced from 1 July 2026 by the Viksit Bharat – Guarantee for Rozgar and Ajeevika Mission (Gramin) Act, 2025 (VB-G RAM G), which guarantees 125 days per rural household a year with more of the cost shared by states; either way a self-targeting wage floor that raises the rural reservation wage — Skill India / PMKVY, National Career Service, ELI/employment-linked incentive schemes, and e-Shram registration for unorganised workers.

Key points

• Derived demand — labour is demanded for what it produces, so demand depends on output demand and productivity.
• MRP_L = W — the profit-maximising hiring rule; MRP_L = P × MP_L under competition.
• Backward-bending supply — income effect overtakes substitution effect at high wages, so hours fall.
• Reservation wage — the minimum acceptable wage; transfers and the rural employment guarantee (MGNREGA, since July 2026 VB-G RAM G) raise it.
• Hicks–Marshall laws — four determinants of the elasticity of labour demand.
• Monopsony — single buyer; MC_L > W; under-employment and under-payment relative to competition.
• Efficiency wage — firms pay above market-clearing to cut shirking and turnover, creating involuntary unemployment.
• Human capital — schooling/training as investment; main cost is foregone earnings.
• Mincer equation — ln W on schooling and experience; coefficient on S is the private return per year.
• General vs specific training — worker pays for general, cost shared for firm-specific.
• Signalling — education may reveal ability rather than add skill; sheepskin effect.
• Compensating differential — extra pay for disamenities and risk.
• PLFS definitions — Usual Status (365 days, major time) vs Current Weekly Status (7 days, 1 hour rule).
• Disguised unemployment — extra workers whose marginal product is near zero, typical of Indian farm households.
• Harris–Todaro — migration responds to the *expected* urban wage, so urban unemployment persists.
• Lewis turning point — where surplus labour is exhausted and the industrial wage must rise.
• Four Labour Codes — in force 21 November 2025, replacing 29 central laws including the Factories, Minimum Wages, Industrial Disputes and BOCW Acts.
• Oaxaca–Blinder decomposition — splits a wage gap into endowment (explained) and discrimination (unexplained) parts.

Formulas and examples

Example 1 — Labour force rates. A district of 10,000 persons aged 15+: 4,200 employed, 300 unemployed and seeking work, 5,500 outside the labour force.

• Labour force = 4,200 + 300 = 4,500.
• LFPR = 4,500/10,000 = 45.0%; WPR = 4,200/10,000 = 42.0%.
• UR = 300/4,500 = 6.67%.
• Note: if 200 of the "outside" group are discouraged workers who would take a job, the labour force becomes 4,700 and UR = 500/4,700 = 10.64% — showing how the unemployment rate understates slack.

Example 2 — Profit-maximising employment. Output price ₹50 per unit; the marginal product schedule and a market wage of ₹1,000 per worker per day:

• Optimum = 5 workers (MRP_L = W). Revenue = 150 × ₹50 = ₹7,500; wage bill = ₹5,000; surplus over labour cost = ₹2,500 per day to cover fixed costs and profit.
• If the wage rises to ₹1,300, employment falls to 3 workers (the 4th worker's MRP_L of ₹1,250 is now below the wage); arc elasticity of demand ≈ (−2/4) ÷ (300/1,150) = −0.500/0.261 ≈ −1.92 (elastic).

Example 3 — Monopsony. Labour supply W = 200 + 20L (₹/day); MRP_L = 1,000 − 10L.

• Total labour cost = W·L = 200L + 20L² → MC_L = 200 + 40L.
• Monopsony: 200 + 40L = 1,000 − 10L → 50L = 800 → L = 16, W = 200 + 20(16) = ₹520/day.
• Competition (W = MRP_L): 200 + 20L = 1,000 − 10L → 30L = 800 → L = 26.67, W = ₹733/day.
• So monopsony cuts both employment and the wage. A minimum wage set at, say, ₹700 would make supply flat at ₹700 up to 25 workers; the firm hires where MRP_L = 700 → L = 30, limited by supply (25 available at ₹700) → employment rises to 25. Here the minimum wage raises wage *and* employment.

Example 4 — Returns to schooling (Mincer). Estimated ln W = 2.9 + 0.08S + 0.05X − 0.0008X².

• A worker with S = 12, X = 10: ln W = 2.9 + 0.96 + 0.5 − 0.08 = 4.28 → W = e^4.28 ≈ ₹72.2 thousand/year in the units of the data.
• With S = 15 (graduate), X = 10: ln W = 2.9 + 1.20 + 0.5 − 0.08 = 4.52 → W ≈ ₹91.8 thousand — about 27% higher, consistent with e^0.08×3 − 1 = 27.1%.
• Experience peaks where 0.05 − 0.0016X = 0 → X = 31.25 years; earnings decline thereafter.

Example 5 — Schooling investment decision. Three extra years of college cost ₹60,000/year in fees and ₹1,80,000/year in foregone earnings; it raises annual earnings by ₹1,20,000 for 30 working years. Discount rate 8%.

• Total cost (ignoring within-period discounting) ≈ 3 × ₹2,40,000 = ₹7,20,000.
• PV of benefits = 1,20,000 × [1 − 1.08⁻³⁰]/0.08 = 1,20,000 × 11.258 ≈ ₹13,51,000, discounted back 3 years (÷1.08³ = 1.2597) ≈ ₹10,72,000.
• NPV ≈ 10,72,000 − 7,20,000 = +₹3,52,000 → invest. Note foregone earnings are 75% of the cost — which is why poor households under-invest in education.

Where it is used

• Government and policy: NSO/MoSPI PLFS design and analysis, Ministry of Labour and Employment wage notifications and Labour Code rules, state minimum-wage advisory boards, Economic Survey employment chapters.
• Central bank and financial research: RBI and research houses track EPFO payroll additions, KLEMS productivity data and real rural wages as inputs to monetary and credit assessment.
• Think-tanks and consultancies: CMIE, Azim Premji University (State of Working India), NCAER, ILO India, World Bank — roles in labour-market data analysis and impact evaluation of MGNREGA, PMKVY and apprenticeship schemes.
• Corporate HR and compensation: compensation benchmarking, attrition and turnover modelling (efficiency-wage logic), wage-cost impact of the new definition of "wages" on PF and gratuity liability, contract-labour compliance.
• Gig and platform economy: Zomato, Swiggy, Urban Company, Ola/Uber — classification of workers, aggregator social-security contributions under the Code on Social Security.
• Exams and teaching: UGC-NET Economics, Indian Economic Service, RBI Grade B, state PSC economics papers, MA entrance tests.

Interview questions

• Q: Why is the labour supply curve sometimes backward bending? A: Beyond a point the income effect of a higher wage outweighs the substitution effect, so the worker buys more leisure and supplies fewer hours.
• Q: What does "labour demand is a derived demand" mean? A: Firms hire labour only for the revenue its output generates, so labour demand shifts with product demand, product price and productivity.
• Q: State the firm's hiring rule and its intuition. A: Hire until MRP_L equals the wage; above that point an extra worker adds more to cost than to revenue.
• Q: Can a minimum wage ever raise employment? A: Yes — under monopsony or efficiency wages, where the wage is below marginal product, a floor can raise both wage and employment; in a competitive market it reduces employment.
• Q: How do India's Usual Status and Current Weekly Status unemployment rates differ? A: Usual Status uses a 365-day majority-time reference; CWS uses a 7-day reference with a one-hour criterion, so CWS rates are higher and capture short-term and seasonal joblessness.
• Q: What is disguised unemployment and why is India's agriculture cited for it? A: Workers appear employed but their marginal product is near zero; family farms absorb surplus labour because there is no alternative, so removing some workers would not cut output.
• Q: Why does rural–urban migration continue when urban unemployment is high? A: Harris–Todaro: migrants compare the *expected* urban wage — the formal wage times the probability of getting such a job — with the rural wage.
• Q: Who pays for general training and who pays for firm-specific training? A: The worker bears general training costs through a lower training wage since the skill is portable; firm-specific training costs and returns are shared, which is why such workers are retained in downturns.
• Q: What is the difference between human capital and signalling explanations of the education premium? A: Human capital says schooling raises productivity; signalling says it reveals pre-existing ability, so the premium would exist even if schooling taught nothing.
• Q: How would you test for gender wage discrimination in PLFS data? A: Estimate separate Mincer equations for men and women and apply an Oaxaca–Blinder decomposition, splitting the gap into differences in characteristics and differences in returns, while noting selection into employment.
• Q: What changed for workers with the four Labour Codes? A: Effective 21 November 2025 they consolidated 29 central laws, introduced a national floor wage, a statutory definition of wages capping excluded allowances at 50%, recognised negotiating unions, and extended social security to gig and platform workers.
• Q: Why is the FLFPR in India low and what moves it? A: Unpaid domestic and care work, safety and mobility constraints, social norms and measurement of own-account farm work; it responds to education, child-care availability, non-farm job access and how surveys count unpaid household work.

Common mistakes

• Treating the unemployment rate as a share of population instead of the labour force, and ignoring that low unemployment with low LFPR can mean a weaker labour market.
• Confusing MRP_L with MP_L (forgetting to multiply by price) or using average rather than marginal product in the hiring rule.
• Saying the substitution effect makes supply bend backwards — it is the income effect that does.
• Assuming a minimum wage always cuts employment, without stating the market structure assumed.
• Omitting foregone earnings from the cost of education, which hugely overstates the return to schooling.
• Quoting the Factories Act, 1948, Minimum Wages Act, 1948 or Industrial Disputes Act, 1947 as current law — they stand replaced by the four Labour Codes from 21 November 2025.
• Mixing up disguised unemployment, underemployment and frictional unemployment, or quoting a CWS rate against a Usual Status series.

Related topics

Economic growth and development · Measuring inequality and poverty · Health and education economics · Urban and regional economics · Public finance and taxation · Industrial economics and market structure