Monday, December 07, 2020

Has the meaning of impact evaluation been hijacked?

 



This morning I have been reading, with interest, Giel Ton's 2020 paper: 
Development policy and impact evaluation: Contribution analysis for learning and accountability in private sector development 

 I have one immediate reaction; which I must admit I have been storing up for some time.  It is to do with what I would call the hijacking of the meaning or definition of 'impact evaluation'.  These days impact evaluation seems to be all about causal attribution. But I think this is an overly narrow definition and almost self-serving of the interests of those trying to promote methods specifically dealing with causal attribution e.g., experimental studies, realist evaluation, contribution analysis and process tracing. (PS: This is not something I am accusing Giel of doing!)

 I would like to see impact evaluations widen their perspective in the following way:

1. Description: Spend time describing the many forms of impact a particular intervention is having. I think the technical term here is multifinality. In a private-sector development programme, multifinality is an extremely likely phenomenon.  I think Giel has in effect said so at the beginning of his paper: " Generally, PSD programmes generate outcomes in a wide range of private sector firms in the recipient country (and often also in the donor country), directly or indirectly."

 2. Valuation: Spend time seeking relevant participants’ valuations of the different forms of impact they are experiencing and/or observing. I'm not talking here about narrow economic definitions of value, but the wider moral perspective on how people value things - the interpretations and associated judgements they make. Participatory approaches to development and evaluation in the 1990s gave a lot of attention to people's valuation of their experiences, but this perspective seems to have disappeared into the background in most discussions of impact evaluation these days. In my view, how people value what is happening should be at the heart of evaluation, not an afterthought. Perhaps we need to routinely highlight the stem of the word Evaluation.

 3. Explanation: Yes, do also seek explanations of how different interventions worked and failed to work (aka causal attribution).  Paying attention of course to heterogeneity, both in the forms of equifinality and multifinality Please Note: I am not arguing that causal attribution should be ignored - just placed within a wider perspective! It is part of the picture, not the whole picture.

 4. Prediction: And in the process don't be too dismissive of the value of identifying reliable predictions that may be useful in future programmes, even if the causal mechanisms are not known or perhaps are not even there.  When it comes to future events there are some that we may be able to change or influence, because we have accumulated useful explanatory knowledge.  But there are also many which we acknowledge are beyond our ability to change, but where with good predictive knowledge we still may be able to respond to appropriately.

Two examples, one contemporary, one very old: If someone could give me a predictive model of sharemarket price movements that had even a modest 55% accuracy I would grab it and run, even though the likelihood of finding any associated causal mechanism would probably be very slim.  Because I’m not a billionaire investor, I have no expectation of being able to use an explanatory model to actually change the way markets behave.  But I do think I could respond in a timely way if I had relevant predictive knowledge.

 Similarly, with the movements of the sun, people have had predictive knowledge about the movement of the sun for millennia, and this informed their agricultural practices.  But even now that we have much improved explanatory knowledge about the sun’s movement few feel this would think that this will help us change the way the seasons progress.

 I will now continue reading Giel's paper…


2021 02 19: I have just come across a special issue of the Evaluation journal of Australasia, on the subject of values. Here is the Editorial section.