OVE’s Experience with Impact (Treatment) Evaluations

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OVE’s Experience with Impact

(Treatment) Evaluations

Presentation prepared for DAC, 15th November 2006

Policy

The general evaluative questions proposed by the IDB’s ex post policy, approved in 2003, are (i) “…the extent to which the development objectives of IDB-financed

projects have been attained.” and (ii) “… the efficiency

with which those objectives have been attained” (para1.1 )

Policy left for practice: sampling, methodology, organizational framework, and the forum for the presentation of results.

Note the task is to evaluate already approved and/or closed projects ( average project time is about six years).

Implementation decisions

Project Sampling Strategy: Option: random or meta-evaluation.

Decision :meta-evaluation.

Method and Project types: (i) process cum naïve or treatment (impact) evaluations. Decision Treatment effect evaluations; and (ii) projects with partial or national coverage. Decision partial coverage models

Organizational. Decisions: (I) separate activity within the office; (ii) evaluations to be carried out both in-house and outsourced.Therefore:

(I) hired staff with appropriate expertise; and (ii) created EVALNET, a register of evaluators;

Forum for presenting results. Decision: overall report (sent to the

Board) with background-working papers (discussed in ad hoc seminars).

Evaluative questions

 what were the problems that the program was designed to tackle?

 what was the policy response, i.e. the design features of the program? (theory based evaluation)

 was the program of a sufficient size given the size of the problem(s)?

 were the program’s deliverables provided in a cost efficient (and cost effective manner)?

What was the incidence and was the program well targeted?

 what was the impact on welfare outcomes of the program?;and

 what were the benefits relative to the cost of the program ?

What was the impact on welfare outcomes of the program?

(I)

(II)

(III)

To answer the question OVE normally use three approaches in the same evaluation:

Naïve evaluation

Regression based (cross-section and panel)

Treatment effects

4

3

2

1

0

(1)

(2)

(3)

(4)

Social Investment Fund (naïve evaluations can be misleading

Profile:

– Social Investment Fund. Panama

– Basic Infrastructure to poor communities

Social Investment Fund - Panama

Data:

– Distribution of benefits by municipalities from administrative data

– Baseline and results of outcome indicators from households surveys

1994-2001

Naïve Impact

Technique:

– Treatment and comparison group using

PSM in double difference. The sample included 75 municipalities.

– Potential to work with a sample of more than 250 smaller geographic units but household survey was not representative at that level

Results:

– Naïve evaluation: the program failed.

Impact evaluation: the program succeeded

14

12

10

8

6

4

2

0

(2)

(4)

Labor Training Project (positive effects)

Employment rate

Labour Training - Dominican Republic

Monthly income

Hours worked per week

Hourly wage Health insurance in primary job

Profile:

– Labor Training program – Dominican

Republic

Data:

– Simple randomization including a followup survey done at 10-14 months after graduation from training

– 786 treated and 563 controls

– Baseline has universe, follow up was a stratified random sample (size determined by standard formulas)

Technique:

– Estimated average Intention-to-treat on treated by simple diff of means, verified with weighted diff and regression analysis (no DD b/c faulty baseline)

Results:

– Employability, income and health insurance access increased. Program succeeded

Public Housing Program

Poverty incidence

Indigence incidence

Ocupation ratio

Education: School attendance

Health: Child undernourishment

Household Completeness

Quality of the dwelling

Overcrowding

Electricity access

Sewerage connection

Access to potable water

(5) 0

Progressive Housing Phase I - Chile

5 10 15

Absolute change (%)

20 25 30

Profile:

– Progressive Housing Phase I – Chile

– Provision of low cost basic dwellings to poor families

Data:

– Household Surveys identified beneficiaries and applicants to the specific housing program

Technique:

– Treatment from beneficiaries and comparison from applicants using PSM.

Single difference from a sample of 508

Beneficiaries and 476 applicants

Results:

– Quality of dwellings improved

– Little or not change in other welfare outcome indicators.

– Difference between naïve versus impact

Costs, benefits, and internal rate of return

1,200

1,000

800

600

400

200

0

Quality of dwellings by household income and Progressive Housing benefits - Chile

0.0

Improving dwelling quality

All non-beneficiaries

PHP-I Beneficiaries

0.2

0.3

0.5

0.7

Quality of the dwellings (Composite Index)

0.8

1.0

Profile:

– Progressive Housing Phase I – Chile

– Provision of low cost basic dwellings to poor families

Data:

– Household Surveys identified beneficiaries and applicants to the specific housing program

Technique:

– The benefits of the program are the additional (necessary) household income required to obtain equivalent dwelling

Results:

– IRR: greater than 18%

– Benefits: Net present value per solution

~1150 US$

80

60

40

20

0

(20)

140

120

100

Rural Roads (decay of benefits over time)

Short-term

Motorized Roads

Rural Roads - Peru

Medium-term

Per capita income per year

Per capita consumption per year

Short-term Medium-term

Non-motorized Roads

Profile:

– Rural Road – Peru

– Construction and upgrade of roads in rural areas

Data:

– Specific survey of beneficiaries.

Baseline collected after program started. Follow-up survey 3 years after program closed

Technique:

– single difference and double difference

Results:

– Positive impact on income and assets’ values of rural households.

– Decreasing impact for motorized roads not for non-motorized roads.

2

1

0

(1)

4

3

(2)

(3)

(4)

(5)

-8

-6

-4

-2

0

-14

-12

-10

-20

-18

-16

2

National Transfer Fund (dosage and multitreatment effects)

Accumulated impact by level of per capita investment - Chile 

Profile:

– National Fund for Regional Development

– Decentralized investment to finance infrastructure and productive projects

3 4 6 9 11

Per capita investment ratio respect control group

Impact by treatment type - FNDR Chile

Education intensive investment

Composite welfare indicator (Index)

Poverty Incidence (%)

17

Diversified investment

25

Data:

– Administrative data for distribution of benefits by municipalities

– Baseline and results of outcome indicators from households surveys 1994-2001. The sample included 343 municipalities.

Technique:

– Impact evaluation using PSM in double difference.

The municipalities grouped by per capita investment using cluster analysis.

Results:

– Positive and increasing impact on poverty incidence (reduction) on per capita investment

– Not impact on poverty if investment is intensive in education

– Greater impact on welfare composite index in municipalities with diversified investment

SCIENCE AND TECHNOLOGY: Research

0 500 ranking

Rechazados

Predicion_rechaza do s

1000

Aprobados

Prediccion_aprobados

1500

Profile:

– Science and Technology – Chile

– Financing for R&D projects

Data:

– All projects that between 1988 and 2004 received the financial support of the program and a stratified sample of projects submitted to the program, which were not financed because they ranked below the threshold defined for being admitted to the financing.

– 2,936 different research projects (932 financed by the

FONDECYT and 1704 not financed) 4,959 publications recoded in the ISI – SCI (1873 by financed researchers and 3806 by not financed researchers).

Technique:

– Discontinuity regression design. The selection process drawn by a “threshold” quality value that separates beneficiaries from non-beneficiaries

Results:

– Unsuccessful. FONDECYT has no significant positive impact on the scientific production of the financed projects.

Technology Development Funds

Employment

Sales

Exports

Productivity (TF)

Patents

Crowding out

Chile Argentina Brazil

+, *

+,

+,

+,

+, *

+, *

+, *

-, *

+,

0,*

-,

-, na

0, * na

-,

+,*

+, *

Profile:

Public grants-credits to firms for innovation

Data:

Administrative data on firms and firm level surveys (OSLO design)

Technique:

Double difference with propensity score matching

Results

Generally positive and significant effects on employment, and sales, but little evidence of effects on patents and total productivity .

EXPERIENCE: Findings Potable Water

0.1

Impact on infant mortality

0

-0.1

-0.2

-0.3

-0.4

All Sample At least Primary

-0.5

Bottom 25% 25%-50%

Expenditure level

50%-75% Top 25%

Positive effect on health outcome

(treatment less than naïve effect)

 heterogeneity of results important. a regressive relationship between treatment effect and income, where more educated (and wealthier) households did better than less educated (and poorer) households

Ramification for project design: projects should include or be coordinated with, as a hypothesis to be tested, a health education component together with potable water expansion.

Balance

But

Since 2004 have produced about 23 evaluations

Cost per evaluation was about $60,000

Problem of obtaining effective counterparts (in Bank and country) to accompany the evaluation from beginning to end. Started outreach program to obtain formal counterparts in the country, and form ad hoc interested specialist for each thematic study.

Mainstream impact evaluations into other evaluations of the Office

Problem of communicating the findings. Started producing different reports for different audiences for the same evaluations.

Still far from the million words of a good picture

Before After

Regression Approach

Panel data

Lny it

 a

0 , i

  i

Lny i , t

1

 

D it

 j m 

 a j , i

LnV i , t j

 j m 

 b j , i

LnV i , t j

  ij

Cross section data

Lny it

 a

0 , i

 

D it

 m  a j , i

LnV i , t j    ij j

Where y is the outcome of interest, D is the dummy for participation in the program, V control variables

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