Thanks Rob, I think this is a valuable space to explore. I like what you’ve written. I’m going to give an assortment of thoughts in this space.
I have tended to refer to the long- vs short- path to impact as “indirect vs direct”, and the many-paths-to-impact vs few-paths-to-impact as “broad vs narrow/targeted”. I’m not sure how consistently these terms are understood. Another distinction which comes up is the degree of speculativeness of the intervention.
There are some correlations between these different distinctions:
Indirect interventions have more opportunities to be broad than direct ones
Indirect interventions are typically more speculative than direct ones
but broad interventions are often more robust (less speculative) than narrow ones
I think it’s typically easier to get a good understanding of effectiveness for more direct and more narrow interventions. I therefore think they should normally be held to a higher standard of proof—the cost of finding that proof shouldn’t be prohibitive in a way it might be for the broader interventions.
I’m particularly suspicious of indirect, narrow interventions. Here there is a single chain for the intended effect, and lots of steps in the chain. This means that if we’ve made a mistake about our reasoning at any stage, the impact of the entire thing could collapse.
Thanks Rob, I think this is a valuable space to explore. I like what you’ve written. I’m going to give an assortment of thoughts in this space.
I have tended to refer to the long- vs short- path to impact as “indirect vs direct”, and the many-paths-to-impact vs few-paths-to-impact as “broad vs narrow/targeted”. I’m not sure how consistently these terms are understood. Another distinction which comes up is the degree of speculativeness of the intervention.
There are some correlations between these different distinctions:
Indirect interventions have more opportunities to be broad than direct ones
Indirect interventions are typically more speculative than direct ones
but broad interventions are often more robust (less speculative) than narrow ones
I think it’s typically easier to get a good understanding of effectiveness for more direct and more narrow interventions. I therefore think they should normally be held to a higher standard of proof—the cost of finding that proof shouldn’t be prohibitive in a way it might be for the broader interventions.
I’m particularly suspicious of indirect, narrow interventions. Here there is a single chain for the intended effect, and lots of steps in the chain. This means that if we’ve made a mistake about our reasoning at any stage, the impact of the entire thing could collapse.
Great clarification, thanks!
To sum up, the shallower and broader the causal map, the more rubust it is.