Also a longer response: I do think the lack of demand is worrying and could be suggestive that these studies are not showing real world effects. I haven’t spent enough time in rural Kenya to know how hard it is to get glasses, but I am updating based on what you say!
I do think it is easy to underestimate how bad your vision has gotten and not use glasses you need. Personally, I have failed to notice that my prescription has gotten out of date and continued to use old glasses, and then finally get around to getting new ones and I do notice a productivity improvement. Since your brain can somewhat compensate, I think it’s easy to underestimate the returns to a correct Rx.
I am very excited to see your longer comment when it’s done—make sure to sent it to both OP and Erin Crossett at GiveWell as well; it sounds like we will all benefit from it!
I share a lot of Drew’s skepticism about the study, especially the experimenter demand effects. If monitoring alone is enough to increase productivity, I think it’s quite plausible that there is some further response (beyond a direct effect of the glasses on vision) to monitoring plus the provision of glasses. Even as a large proponent of quantile regression in many applications, I do think OLS is more appropriate for a cost effectiveness analysis. A median shift could be consistent both with a much larger or much smaller (even negative) impact on aggregate utility.
However, I do think the point about glasses as an experience good is a good one and could quite possibly be at play here. If getting glasses for work is not a normal activity, it could be easy to underestimate the benefits of doing so.
Connor makes great points as always, and I appreciate the detailed response and the openness Lauren!
I very much agree with you both that glasses are an experience good and people systematically underestimate the value as their eyesight slowly gets worse. I think it’d be very interesting to study different ways of stimulating demand and generating awareness. I’m especially interested in the free screening model some systems like LV Prasad have adopted.
And to be clear, I would guess that providing reading glasses is cost-effective based on the disability aversion alone. People were very happy to glasses and did benefit from them. I am just skeptical there are many further income benefits beyond that. On that topic, I have finished a first draft of the comment, so hopefully can circulate soon!
Also a longer response: I do think the lack of demand is worrying and could be suggestive that these studies are not showing real world effects. I haven’t spent enough time in rural Kenya to know how hard it is to get glasses, but I am updating based on what you say!
I do think it is easy to underestimate how bad your vision has gotten and not use glasses you need. Personally, I have failed to notice that my prescription has gotten out of date and continued to use old glasses, and then finally get around to getting new ones and I do notice a productivity improvement. Since your brain can somewhat compensate, I think it’s easy to underestimate the returns to a correct Rx.
I am very excited to see your longer comment when it’s done—make sure to sent it to both OP and Erin Crossett at GiveWell as well; it sounds like we will all benefit from it!
I share a lot of Drew’s skepticism about the study, especially the experimenter demand effects. If monitoring alone is enough to increase productivity, I think it’s quite plausible that there is some further response (beyond a direct effect of the glasses on vision) to monitoring plus the provision of glasses. Even as a large proponent of quantile regression in many applications, I do think OLS is more appropriate for a cost effectiveness analysis. A median shift could be consistent both with a much larger or much smaller (even negative) impact on aggregate utility.
However, I do think the point about glasses as an experience good is a good one and could quite possibly be at play here. If getting glasses for work is not a normal activity, it could be easy to underestimate the benefits of doing so.
Connor makes great points as always, and I appreciate the detailed response and the openness Lauren!
I very much agree with you both that glasses are an experience good and people systematically underestimate the value as their eyesight slowly gets worse. I think it’d be very interesting to study different ways of stimulating demand and generating awareness. I’m especially interested in the free screening model some systems like LV Prasad have adopted.
And to be clear, I would guess that providing reading glasses is cost-effective based on the disability aversion alone. People were very happy to glasses and did benefit from them. I am just skeptical there are many further income benefits beyond that. On that topic, I have finished a first draft of the comment, so hopefully can circulate soon!