Difference in Difference Impact Study

Publication
In addition to the randomized control trial (RCT), One Acre Fund uses the Difference-in-Difference (diff-in-diff) statistical technique to verify our everyday measurements. This memo covers our most comprehensive difference-in-difference studies.

Our annual impact evaluation efforts consist of obtaining wide geographic representation of One Acre Fund farmers and comparing their harvest yields and agricultural profit to those of similarly situated neighboring farmers who are subject to the same micro-climate conditions. We attempt to minimize differences between these groups by (1) excluding farmers who are vastly different (e.g. have large land sizes, or do not rely on agriculture) (2) select farmers who are recommended as “interested” in joining One Acre Fund the following year and (3) matching One Acre Fund and comparison farmers on relevant characteristics during our statistical analysis.

The value of this measurement strategy is that we can do many measurements, over a wide geographic area, over many crops. In 2015 for example, we obtained harvest information directly from 16,000 fields. This gives us plenty of data, and enables us to make programmatic changes in response to that data. However, we also make targeted use of more rigorous approaches (randomized control trials, or RCTs, and Difference-in-Difference, or Diff-in-Diff) to verify the quality of our everyday measurements.