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Impact evaluation helps deliver development projects (English)

Does research add value to aid? Specifically, does impact evaluation research help or hinder the delivery of development projects? This paper analyzes the question by constructing a new data set of 100 impact evaluations and 1,135 projects approved by the World Bank between 2005 and 2011. The analysis finds that the delivery of projects with impact evaluation is significantly timelier: common delays are avoided and the gap between planned and actual disbursements is reduced by half. Evidence-based mid-course corrections, a clearer implementation road map, strengthened capacity on the ground, and observer effects are possible channels to explain the results. Hopefully, this analysis will stimulate discussion over the optimal balance between project financing and the impact evaluation research needed to deliver development outcomes.


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    Di Maro,Vincenzo, Legovini,Arianna, Piza,Caio

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    Policy Research Working Paper

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    The World Region,

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    Impact evaluation helps deliver development projects

  • Keywords

    economic and sector work;Finance & Private Sector;high school financial education;research need;net official development assistance;effectiveness of aid;composite error term;quality at entry;impact of intervention;availability of fund;parameter of interest;difference in outcomes;construction of infrastructure;Public Sector Governance;quality assurance process;general budget support;transfer of resource;public policy process;point of departure;average treatment effect;loan size;fixed effect;project financing;disbursement path;project selection;point estimate;project duration;institutional factor;optimal balance;adverse selection;project plan;descriptive statistic;development policy;future research;health facility;literature review;empirical analysis;disbursement rate;estimation strategy;standard error;private good;conceptual framework;standard deviation;administrative datum;survey data;operational tool;infrastructure sector;unbalanced panel;field staff;counterfactual analysis;Social Protection;positive relationship;project ratings;market-oriented reforms;positive externality;evaluation research;Business Climate;time-invariant variable;idiosyncratic component;fragile states;unobserved characteristic;public good;fact sheet;consistent estimate;strategic approach;present evidence;reputational risk;structured learning;experimental treatment;unobserved variable;analytical tool;midcourse correction;research design;real time;operational research;donor funding;potential contribution;portfolio review;knowledge generation;Agricultural Investment;cultural change;research capacity;project size;institutional environment;satisfactory answer;qualitative assessment;aid flow;knowledge gap;project approval;Macroeconomic Policy;national policy;open access;remedial action;project operation;idiosyncratic factors;research assistance;beneficiary assessment;financial flow;transmission mechanism;positive impact;explanatory factors;civil liberty;Political Economy;essential medicines;aid financing;external review;monitoring indicator;donor agencies;empirical investigation;field experiment;political condition;measure of use;project datum;negative coefficient;business economics;direct transfer;foreign assistance;anecdotal evidence;



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Di Maro,Vincenzo Legovini,Arianna Piza,Caio

Impact evaluation helps deliver development projects (English). Impact Evaluation series,Policy Research working paper ; no. WPS 7157 Washington, D.C. : World Bank Group.