can public employment scheme increase equilibrium wages? evidence from a natural experiment (nreg)...
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Can Public Employment Scheme Increase Equilibrium Wages? Evidence From a Natural Experiment (NREG) in India
Authors
• Erlend Berg• Sambit Bhattacharyya• D Rajashekhar• R Manjula
Presenters• Devesh Bansal• Akash Kalyani• Astha Malhotra• Avinash Totla
INTRODUCTION TO THE PAPER
Research Question/ Aim
• Study the impact of National Rural Employment Generation (NREG) Scheme on agriculture wages.
Motivation
1) Workfare programmes (NREG) are an alternate poverty reduction tool (NREG—Wages--Poverty).
2) NREG itself with the expenditure close to 0.5% of India’s GDP (2010) is worth studying.
3) Recent political debate – letter to PM Modi4) Obviously....part of syllabus
What’s NREG? As if u guys don’t know...• NREG Scheme is a rural employment programme which aims to
provide wage employment to un-under employed landless agricultural labourers, locally, specially during agriculture slack season.
• Important point......NREG was rolled out in three phases from 2006 to 2008 with initial focus on poorest districts of India.
USP of this Paper
• Studies the largest workfare programme with the size of $7.88bn, coverage of 55mn households, and varied experience of ALL states and rural districts. Thus conclusions derived will not be NREGA specific but quite general in nature.
• Data: Uses a very detailed..monthly, district wise, gender wise, labour category wise data. This helps us to achieve robust results
DATA USED
• Agriculture Wages in India (AWI) series has been used for the period 2000-2011.• CPI for rural labourer has been used to fix the
base at Jan 2000.
DATA CATEGORIES
AWI
Unskilled
Field Labour
Ploughing Reaping Sowing Weeding
Herding Other Labour
Skilled (Only Male)
Carpenter Cobbler Blacksmith
Variable of Interest
• Focus of the paper is on Field Wage Labour category (both male and female) because-
a. Huge proportion of agricultural wage labour undertaken in India falls under this category.
b. Data quality and measurement error issues associated specially with herding data.
c. Falls under Unskilled labour category which is expected to get influenced by NREG
AWI Data Collection
• 1 centre is selected for data collection from every district• Advantages of AWI
1. Detailed Data - month wise, district wise, gender, labour category wise data set
• Disadvantages of AWI1. Village/Centre chosen may not be representative of district and officials may
not be trained enough.• Still AWI is good data source ASSUMING no relation b/w measurement
errors (or non randomness of centre selected) and NREG rollout.
EXAMPLE
• Suppose for District(1), January the wages are as follows –
• Average Male Wages = 96.7 • Average Female Wages = 77.5• Wages = (77.5+96.7)/2 = 87.1• Real Wages = 87.1/CPI
CATEGORY WAGES (MALE) WAGES(FEMALE)
Ploughing 80 70
Reaping . 50
Sowing 110 100
Weeding 100 90
Does AWI simply report NREG statutory wages?• If it is the case then our estimation of impact of NREG on
agricultural wages won’t hold.• To check this – Statutory NREG wages were compared
with Wages (just computed) at a random points of time (Jan-March 2009). • Seven districts which had same wages were dropped
from the data set, though it is plausible to have same wages.
Summary Statistics
EMPIRICAL STRATEGY
Empirical Strategy (Fixed Effects with DID)
Yit : the natural logarithm of real daily wages in district i in month tTit : Binary variable for NREG treatment for district i in month tα, and Θ are constants
Issues
Tit does not capture the intensity of
NREGA in month t
We cannot differentiate between NREGA wage
increase from other macroeconomic wage
increases
Selection bias for districts in respective
phases
Autocorrelation
Our ideal experiment would be to calculate the difference between treatment and counterfactual
Empirical Strategy – Published Paper(Fixed Effects with DID)
Yit : the natural logarithm of real daily wages in district i in month tαi : district fixed effects βy: yearly fixed effects γm: monthly fixed effects Tit: Treatment dummyEit : number of months for which Nrega is active in the district [Trends] : district-wise time trendεit : random error term
Autocorrelation: Every regression incorporates robust standard errors, clustered at the district level
*We think that the district wise time trend effects are accounted for by Zit or Zi*t
Empirical Strategy – Published Paper(Fixed Effects with DID)
y1(1)
y1(0)
y0(0)
t=0 t=1
Wages
Graphic Explanation
y1(0’)
RESULTS
Main Results:The Impact of NREG on wage rates for unskilled field labour
• The dependent variable is log daily field wages in fixed January 2000 prices, observed between May 2000 and June 2011
• ‘Treated’ is a binary variable equal to 1 if NREG was active in that district at that time
• In (1), positive and significant coefficient indicates that real wages in NREG-treated districts are (approx) 7% higher
• In (2), coefficient becomes insignificant
• In (3) coefficient is positive and significant (different interpretation)
• District trends take account of any bias relating to wage growth rates that vary across districts independently of NREG
• On average, introduction of NREG in a district increases the growth rate of agricultural wages by 0.4% per month, on top of any underlying trends
• In (5) checking if the impact of NREG diminishes over time (not significant)
c (3)Field labour wages
(4)Field labour wages
(5)Field labour wages
Exposure
[Exposure]2
District, Year & month fixed effects
District trends
0.003***(0.001)
Yes
No
0.004***(0.001)
Yes
Yes
0.003***(0.001)
2X10-5
(2.7X10-5)Yes
Yes
ObservationsDistrictsStates
1527220918
1527220918
State-wise estimates
• To study regional heterogeneity, the main regression is also estimated state by state
• When wages are regressed on the binary variable, the coefficient is not significant at the 5% level for any state
• When wages are regressed on the Exposure variable:• Positive and significant effects for
Rajasthan and Andhra Pradesh (among star performers in Dreze and Khera(2009))
• Positive and significant for Kerala and West Bengal (tend to do well on many social metrics)
• Positive and marginally significant effects in Bihar and Haryana
• For the rest the effect is not positive and significant 21
Seasonal Variation
• To study whether the effect of NREG is uniform throughout the year, wage rates are regressed on the exposure variable interacted with 12 monthly fixed effects
• (regression equation)• it appears NREG exposure pushes
up wages only when labour is relatively scarce
• While it is reasonable that wages should increase more when the demand for labour is high, it is also plausible that the effect on earnings is stronger in the slack season
Impact on the Skilled Labour
• Table 4 presents results of regression of wages in skilled labour categories on NREG Exposure
• The intended beneficiaries of NREG are unskilled agricultural labourers
• To the extent that skilled and unskilled labourers operate in separate labour markets, the wages of skilled labourers are insulated from the effect of the programme
07/1
1/20
14
23
(1)Carpenter’s
wages
(2)Blacksmith’s
wages
(3)Cobbler’s
wages
Exposure
District, year & month fixed effects
District Trends
0.001(0.001)
Yes
Yes
0.001(0.002)
Yes
Yes
0.001(0.002)
Yes
Yes
ObservationsDistrictsStates
1694620618
1433118115
1084215612
• No evidence of strong correlation between wages of the skilled categories and field labour wages- corroborates hypothesis of separate markets
07/1
1/20
14
24
Impact on Gender Wage Gap
• On average, Female field labourers are paid 79% of male field labourers wage
• Differential effect of NREG exposure on women’s wages relative to men’s wages is very small and insignificant
• Analysis is repeated with binary treatment variable and no discrete jump in wages is identified
• NREG Exposure neither diminishes nor enlarges the gender wage gap
Phase-wise Effects
• NREG effect is positive and strongly significant for all three phases
Jan 2000
April 2007 NT=1;NE=1
Dec 2007 NT=1;NE=9
April 2008 NT=1;NE=13
Dec 2008 NT=1;NE=21
Jan 2000
April 2004 PT=1;PE=1
Dec 2004 PT=1;PE=9
April 2005 PT=1;PE=13
Dec 2005 PT=1;PE=21
NREGA ExperimentDistrict i in Phase-2
Placebo ExperimentDistrict i in Phase-2
NT= NREG Treatment VariableNE= NREG Exposure VariablePT=Placebo Treatment VariablePE=Placebo Exposure Variable
Robustness Check: Placebo Test
Robustness Check: Placebo Test
• Estimated effect of Placebo Treatment is not significant• Coefficient of Placebo Exposure is close to zero and insignificant• Placebo test validates the result that the estimated effect on real wages
were caused by NREG
Conclusion
• NREG boosts the growth rate of average real daily agricultural wages @4.8% per annum
• Effect of NREG appears to be gender neutral and concentrated in main agricultural season
• NREG appears well targeted programme as it mainly effects unskilled wages• Effect is mainly concentrated in following states: AP,BH,HR,KL,RJ &WB• Paper have not assessed the cost-effectiveness of NREG programme• Net welfare effects are ambiguous; didn’t account the effect of wage
increase on employers and effect of workfare on the labour supply of poor