Presentation slides

121 Pages·2016·1.3 MB·English

by  Elizabeth Bond

Sampling and Sample Size
Rachel Glennerster
MIT
Course Overview
1. What is Evaluation?
2. Measurement & Indicators
3. Why Randomize?
4. How to Randomize?
5. Sampling and Sample Size
6. Threats and Analysis
7. Generalizability
8. Project from Start to Finish
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Sampling and Sample Size
Rachel Glennerster
MIT
Which of these most likely to describe
estimates from 8 well implemented RCTs?
I. II.
70%
A. I
B. II
C. Neither 15% 15%
A. B. C.
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Which is the best description of II?
I. II.
89%
A. Imprecise estimate
B. Biased estimate
C. Imprecise but unbiased
11%
0%
A. B. C.
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Bias and precision

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n estimates
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truth
Less bias (Randomization)
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Outline
• Introduction
• Hypothesis testing
• What influences power?
• Power in clustered designs
• Calculating power in practice
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Outline
• Introduction
• Hypothesis testing
• What influences power?
• Power in clustered designs
• Calculating power in practice
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Introduction
We evaluate bringing tutors into schools
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