In this episode of Survey & Beyond: The Data Collection Podcast, host Marta Costa is joined by Douglas Johnson, a Senior Statistician on the Technical Team at IDinsight. Together, they share groundbreaking approaches to survey sampling that balance rigor with cost-effectiveness, especially in regions where traditional census data is unavailable or unreliable.

What You’ll Learn:

How traditional sampling methods like the "right-hand rule" fall short in delivering replicable, unbiased results
Why satellite imagery and rooftop data are transforming household survey sampling methodology
The practical implementation of rooftop sampling and how it improves upon conventional approaches
How grid-based sampling works and when it's most appropriate to use
The technical requirements and organizational considerations for implementing new sampling methods
Why AI and technology will enhance but not replace human-conducted household surveys

Douglas Johnson is a Senior Statistician on the Technical Team at IDinsight, specializing in survey sampling methodology and data quality improvement for global development research. With extensive expertise in statistical analysis and survey design, he leads innovative work through IDinsight's Data Delta initiative, which aims to make household surveys better, faster, and more cost-effective. Johnson has pioneered new approaches to survey sampling, including rooftop sampling methodology, and has worked with organizations like Meta, the World Bank, and UNICEF to revolutionize data collection in hard-to-reach areas.

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Episode Highlights:

0:00 Intro
2:27 Why Traditional Sampling Is Broken
4:44 Why Satellite Imagery Changes the Game
6:42 The Right-Hand Rule Debunked
10:37 The Road to Rooftop Sampling
13:08 Lessons From the Field
16:04 Is Grid-Based Sampling Worth It?
19:19 Skills and Tools You’ll Need
25:00 The Future of Sampling
26:56 AI and the Role of Human Interaction

Episode Resources:

Douglas Johnson on LinkedIn
IDinsight Website
Marta Costa on LinkedIn
Dobility Website
SurveyCTO Website
Right-Hand Rule Sampling" Blog Post
Grid-based Sampling Blog Post
WorldPop Website
GHS-POP Website
Google My Maps Website
MapSolve Website

Guest Resources:

Right-hand rule sampling
- Blog post on why right-hand rule sampling leads to biased results
Grid-based sampling
- Blog post introducing grid-based sampling
- Blog post on lessons learned using grid-based sampling
- Code to implement grid-based sampling
- Additional code to cluster grids
Rooftop sampling
- Working paper showing that rooftop sampling leads to relatively little bias
- Code and guidance to implement rooftop sampling
Voter roll sampling
- Academic paper showing that voter rolls have high coverage in rural India