33 ms·

While you raise valid limitations of the study, those limitations do not provide a valid cuse to dismiss the result outright. Random assignment to different lev

While you raise valid limitations of the study, those limitations do not provide a valid cuse to dismiss the result outright. Random assignment to different levels of "cuddles" in humans is probably not ethical,and longitudinal studies are expensive. To get a grant funding a longitudinal study you usually have to have a) animal model based evidence from the literature b)have already demonstrated in humans the phenomenon cross-sectionally. As a side note, your comment would have been perfectly reasonable sounding if you had left off the first two words, and the last sentence. But you didn't.

gwern 9y ago
None of that is true. We have a long history of epigenetics studies which let us known this is almost certainly yet another failure. Random assignment is not unethical under many designs (exercise for the reader: think of one. Hint: draw inspiration from economics), is not necessary to improve over what they did, and longitudinal designs at their simplest merely require two sampling periods. It is also untrue that you 'usually' have to have demonstrated it in animals or cross-sectionally because many longitudinal studies are convenience samples, record-based or population registries, or collect large numbers of measurements to see what comes out in later analyses of things they hadn't thought of before.
- SubiculumCode 9y ago
  Clearly I was not claiming that random assignment is un ethical generally, but specifically in the case of assigning the degree of physical affection/cuddling to a baby is probably unethical. As someone who has been involved in multiple longitudinal studies, although not in epigenetics, I can say that they are more expensive. In terms of what I said about prior evidence, I was coming from a cognitive psych background where we do not typically deal with record-based data. We deal with participants directly. It is expensive and time consuming. Longitudinal studies usually follow cross-sectional evidence.
  - gwern 9y ago
    > but specifically in the case of assigning the degree of physical affection/cuddling to a baby is probably unethical. Alright, since you refuse to think, I'll give it to you for free: do an intent-to-treat design with incentives for additional cuddling for either the parents or hired helpers like nannies, or passive controls; as no infant receives less physical affection than they would otherwise, no one is hurt by the randomization and it is not unethical, but you still get a causal effect. (Not all of them will use it, and the ones who do, the difference will be smaller than if you could remove cuddling, but that's merely a matter of power.) Such designs are often used in economics, and are applicable to many topics where randomization is considered infeasible for 'ethical' reasons: if you have a limited supply of X, it can be allocated by lottery; if you want to measure the impact of health insurance, surely this is unethical? How could you ever study it? But no, you have limited Medicare funds, so you simply allocate by lottery. Charter schools, lead poisoning, vaccines, basic incomes, daycare, enrichment programs, cuddle subsidies etc. The winners get the additional treatment while the losers serve as baseline controls, finessing the ethical problems. As it is usually the case that there's not enough money to deliver the claimed-beneficial intervention to all possible beneficiaries, it's quite a general strategy. > As someone who has been involved in multiple longitudinal studies, although not in epigenetics, I can say that they are more expensive. I didn't say that they weren't, just that they were only somewhat more expensive, and they can be done cheaply in a number of ways. There are considerable economies of scale in these things - look at the UK Biobank.
    - SubiculumCode 9y ago
      First, you may not be aware of yourself sufficiently, but you are being a real asshole. Second, you are correct that I didn't consider that design. This may be because it is a little stupid, or at least impractical without the right target population. For example, if I wanted to study the effects of malnutrition it would make sense to do random assignment to individuals to food and food+extrafood conditions, but only if my sample contained a number of malnourished kids. If I took my sample from middle class America, and I assigned them to food and food+plusmorefood conditions (via force feed I guess?), I'd be studying obesity more likely than malnutrition. Levels matter. I'd guess that the primary interest in the present research is the effect of not getting physical affection as an infant. The effect between some and more affection, is probably qualitatively different than none and some affection.
laretluval 9y ago
So the flaws don't provide a valid case to dismiss the result because it would have been hard to do it right?
- SubiculumCode 9y ago
  I don't believe I was trying to make that case. My point was that no single design is perfect, and that research is an iterative endeavor, where initial (easy) evidence is collected prior to collecting expensive and time consuming but more definitive evidence.
im3w1l 9y ago
I think an experiment of the form no intervention vs more hugs would be ethical.

gwern 9y ago

None of that is true. We have a long history of epigenetics studies which let us known this is almost certainly yet another failure. Random assignment is not unethical under many designs (exercise for the reader: think of one. Hint: draw inspiration from economics), is not necessary to improve over what they did, and longitudinal designs at their simplest merely require two sampling periods. It is also untrue that you 'usually' have to have demonstrated it in animals or cross-sectionally because many longitudinal studies are convenience samples, record-based or population registries, or collect large numbers of measurements to see what comes out in later analyses of things they hadn't thought of before.

SubiculumCode 9y ago
Clearly I was not claiming that random assignment is un ethical generally, but specifically in the case of assigning the degree of physical affection/cuddling to a baby is probably unethical. As someone who has been involved in multiple longitudinal studies, although not in epigenetics, I can say that they are more expensive. In terms of what I said about prior evidence, I was coming from a cognitive psych background where we do not typically deal with record-based data. We deal with participants directly. It is expensive and time consuming. Longitudinal studies usually follow cross-sectional evidence.
- gwern 9y ago
  > but specifically in the case of assigning the degree of physical affection/cuddling to a baby is probably unethical. Alright, since you refuse to think, I'll give it to you for free: do an intent-to-treat design with incentives for additional cuddling for either the parents or hired helpers like nannies, or passive controls; as no infant receives less physical affection than they would otherwise, no one is hurt by the randomization and it is not unethical, but you still get a causal effect. (Not all of them will use it, and the ones who do, the difference will be smaller than if you could remove cuddling, but that's merely a matter of power.) Such designs are often used in economics, and are applicable to many topics where randomization is considered infeasible for 'ethical' reasons: if you have a limited supply of X, it can be allocated by lottery; if you want to measure the impact of health insurance, surely this is unethical? How could you ever study it? But no, you have limited Medicare funds, so you simply allocate by lottery. Charter schools, lead poisoning, vaccines, basic incomes, daycare, enrichment programs, cuddle subsidies etc. The winners get the additional treatment while the losers serve as baseline controls, finessing the ethical problems. As it is usually the case that there's not enough money to deliver the claimed-beneficial intervention to all possible beneficiaries, it's quite a general strategy. > As someone who has been involved in multiple longitudinal studies, although not in epigenetics, I can say that they are more expensive. I didn't say that they weren't, just that they were only somewhat more expensive, and they can be done cheaply in a number of ways. There are considerable economies of scale in these things - look at the UK Biobank.
  - SubiculumCode 9y ago
    First, you may not be aware of yourself sufficiently, but you are being a real asshole. Second, you are correct that I didn't consider that design. This may be because it is a little stupid, or at least impractical without the right target population. For example, if I wanted to study the effects of malnutrition it would make sense to do random assignment to individuals to food and food+extrafood conditions, but only if my sample contained a number of malnourished kids. If I took my sample from middle class America, and I assigned them to food and food+plusmorefood conditions (via force feed I guess?), I'd be studying obesity more likely than malnutrition. Levels matter. I'd guess that the primary interest in the present research is the effect of not getting physical affection as an infant. The effect between some and more affection, is probably qualitatively different than none and some affection.

laretluval 9y ago

So the flaws don't provide a valid case to dismiss the result because it would have been hard to do it right?

SubiculumCode 9y ago
I don't believe I was trying to make that case. My point was that no single design is perfect, and that research is an iterative endeavor, where initial (easy) evidence is collected prior to collecting expensive and time consuming but more definitive evidence.

im3w1l 9y ago

I think an experiment of the form no intervention vs more hugs would be ethical.