## A Curated List of Our Postings on Technical Topics – Your One-Stop Shop for Methodology

**Random Assignment, Registration and Reporting**

Doing stratified randomization with uneven numbers in the Strata [3]

How to randomize using many baseline variables [4]

Public randomization ceremonies [5]

Designing experiments to measure spillover effects [6]

Mechanism experiments [7] and opening up the black box [8]

Sample weights and RCT design [9]

A pre-analysis plan check-list [10]

The New Trial Registries [11]

What isn’t reported in impact evaluations but maybe should be [12]

**Propensity Score Matching**

Guido Imbens on clustering standard errors with matching [1]

Testing different matching estimators as applied to job training programs [13]

The covariate balanced propensity score [14]

**Difference-in-Differences**

The often unspoken assumptions behind diff-in-diff [15]

**Other Evaluation Methods**

The synthetic control method [16], as applied to regulatory reforms

Regression discontinuity with an implicit index [17]

Using spatial variation [18] in program performance to identify impacts

Small n impact evaluation methods [19]

Can we trust shoestring evaluations? [20]

**Analysis**

Regression adjustment in randomized experiments (part one [21], part two [22])

When to use survey weights [23] in analysis

Adjustments for multiple hypothesis testing [24]

Bounding approaches to deal with attrition [25]

Linear probability models versus probits [26]

Dealing with multiple lotteries [27]

Estimating standard errors with small clusters (part one [28], part two [29])

Decomposition methods [30]

Estimation of treatment effects with incomplete compliance [31]

**Power Calculations and Improving Power**

Does the intra-cluster correlation matter for power calculations if I am going to cluster my standard errors? [32]

Power calculations for propensity score matching [33]

Power calculations 101: dealing with incomplete take-up [34]

Collecting more rounds of data to boost power [35]

Improving power in small samples [36]

**On External Validity**

Weighting for external validity [37]

Will that successful intervention over there get results here? [38]

Learn to live without external validity [39]

Why the external validity of regression estimates can be less than you think [40]

Why similarity is the wrong concept for external validity [41]

A rant on the external validity double standard [42]

**Jargony Terms in Impact Evaluations**

The Hawthorne Effect [2]

The John Henry Effect [43]

Placebo effects [44]

Clinical Equipoise [45]

**Stata Tricks**

Graphing impacts with Standard Error Bars [46]

Calculating the intra-cluster correlation [47]

- Tags:
- Life the Universe and Everything [48]
- randomization [49]
- external validity [50]
- propensity score [51]
- statistical power [52]
- Difference-in-difference [53]