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2014 Rossi Award lecture:* beyond internal validity.

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Summary
This summary is machine-generated.

The evaluation field must now prioritize external validity and cost-effectiveness. Recommendations include a two-stage evaluation process and using random assignment in program operations to improve impact assessment.

Keywords:
content areadesign and evaluation of programs and policiesmethodological developmentoutcome evaluation (other than economic evaluation)

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Area of Science:

  • Evaluation Science
  • Impact Assessment Methodology
  • Program Effectiveness Research

Background:

  • The evaluation field has historically focused on internal validity, largely resolved by the acceptance of random assignment for impact evaluation.
  • Current evaluation practices face challenges with external validity and the high cost and low success rate of experimental designs.

Discussion:

  • Shifting focus to external validity is crucial for the evaluation profession.
  • Addressing the cost and low hit rate of experimental evaluations is necessary for practical application.

Key Insights:

  • Random assignment is now the standard for internal validity in impact evaluations.
  • External validity and cost-efficiency are the next frontiers in evaluation science.
  • A two-stage evaluation strategy can improve resource allocation and identify effective interventions.

Outlook:

  • Future evaluations should incorporate strategies to enhance external validity.
  • Implementing a phased evaluation approach (Stage 1 and Stage 2) can optimize resource use.
  • Integrating random assignment into routine program management can yield valuable insights.