2023-07-12-世界银行-公共工程项目是否具有持续影响_LMIC实验研究综述（英）_42页_918kb

Summary of Public Works Programs in LMICs

The review analyzed 11 experimental studies from low- and middle-income countries (LMICs) to assess the short and medium-run impacts of public works programs. Key findings include:

1. Short-term Impacts

• Public works programs significantly increased employment and earnings during the program, with average effects of 29.3 percentage points on employment and $51.3 USD on monthly earnings.
• However, these effects faded in the medium run, with average post-program impacts of just 3.4 percentage points on employment and $7.8 USD on earnings, not reaching statistical significance.

2. Medium-term Impacts

• Effects on economic outcomes were largely not sustained 6–66 months after program completion, despite small positive effects in a few cases such as through savings or self-employment investments.
• Food consumption expenditure did not significantly improve across studies, despite increases in employment and earnings.

3. Cost-effectiveness and Limitations

• Impacts on earnings were substantially lower than the maximum potential program earnings due to forgone earnings from other employment, raising questions about cost-effectiveness.
• Only limited evidence exists on the long-term effects of public works programs on women's empowerment and psychological well-being, with inconsistent results.

4. Policy Implications

• Public works programs are effective in the short run for providing employment but struggle to sustain impacts in the medium run.
• Complementary interventions such as skills training and savings facilitation are needed to support transitions to more permanent employment and improve long-term outcomes.
• Future research should focus on collecting cost data, using broader measures of well-being and empowerment, and experimenting with "public works plus" packages.