This is really great, and thanks for highlighting where to get the data - I wouldn't have heard about this otherwise.

Regarding this:

For instance, it was found that areas with older, lower education, and more conservative voter-support had a lower proportion of meat purchases

That's definitely an interesting finding. Is it possible that some of these factors, such as lower education, are associated with lower income - thus less able to afford a lot of meat? Alternatively, might there also be differences in where people shop; perhaps they get meat from another store or local butcher?

I agree that sales data can be much more informative, or informative in different ways, than self-report data, so this is really nice to see

Thanks for your comment @Robert Van Buskirk, and great that you are also thinking of ways to incorporate uncertainty into CEAs. You note that your way also solves 'the same problem', but a key aspect of what we are arguing (and what others have suggested) is not just that a proper monte carlo approach avoids objective issues with an interval-based approach, but that it provides a wealth of more nuanced information and allows for much more discerning assessments to be made. This is approximated by the approach you suggest, but not fully realised. For example ‘A histogram of the full set of CE results is then constructed to illustrate the full range of possible CE values’ - but by definition the histogram won’t include the full range of possible values because values beyond the average of the top and bottom thirds are not included in the calculations. This might obscure or underestimate the possibility of extreme outcomes.

My second concern would just be that if one has the capacity to define what the average of the bottom third of the expected values are, and the average of the top third, this is in all likelihood enough information for defining an approximate distribution, or one could simply select a uniform distribution. In that case, why not just do a proper monte carlo? The main answer to this is often just that people don’t have the confidence to consider a possible probability distribution that might work, and that was the key thing I’m trying to help with in developing and sharing this application

Thanks for sharing your experience on becoming vegetarian! There were also several people in the survey who said things such as just finding it disgusting.

Thanks for sharing this additional information and numbers. My concern basically lies in what I see as a large difference between making meatless/plant-based options a default or more easily available choice vs. removing anything that is not plant-based from campus. The empirical information from interventions above relate to interventions that are in the form of switching a default and not about entirely removing an option, and it is with the 'forcing of a shift in behavior' as you put it where I can imagine a lot more negative sentiment among those who do not agree.

Even on plant-default days in a seemingly successful implementation mentioned above, over 40% of students picked a non plant-based option. Those students would presumably not be too happy if the option were entirely removed.

"This is undoubtedly a massive opportunity to kickstart positive change at a large institutional scale with minimal cost or risk involved" ... "The primary motivation of this campaign may be for universities to limit their contribution to climate change and to shift public opinion in favour of a plant-based food system"

Although I'm supportive of moves towards plant-based diets and better plant-based options being available, I wonder how confident one can be that this is truly minimal risk, especially with regards to the stated goal of shifting public opinion in favour of plant-based food systems. Do we know what proportion of students would really favour not have access to non-plant-based foods on campus (representative data, rather than petitions etc.)? If a majority are in favour, could this kind of action produce a very disgruntled minority who feel these things are being forced upon them and are resistant for the remainder of their lives to similar or other forms of animal advocacy. I'd be interested to know if there is any data/other relevant information or discussion with respect to these possible risks, and the popularity of such changes among the whole student body

Hi mcint, I've made some changes to the plots such that the colors are now darker for higher ratings, and the rating numbers and meaning are all positioned at the top, so it should be less open to misinterpreting what information is presented.

The ordering of the items is just in ordering of descending mean ratings.

Glad you've found it useful!

Indeed, the personal conversation is a bit of a black box and in open responses people gave to provide more information, most did not note specific content or arguments but rather just the type of person it was - often family members, partners, and close friends. It doesn't necessarily seem like the conversations were in the form of people trying to 'convince' them or argue with them about becoming vegetarian

Hi Matt, yes indeed it could also be due to survivorship bias, or a combination of survivorship and the suggestions I made.

Not based on anything empirical but I imagine that health related reasons are probably especially vulnerable to drop out because potentially all it takes is finding some other diet that promises health benefits and the person might make a switch.

Great to hear Jacob!

Thanks for highlighting this possible source of confusion. The ' - ' is  intended to be like a literal minus sign, but it could be read more like a spectrum with Longtermism tending left and Neartermism tending right which seems to be how you (and possibly others) read it. I've adapted the labeling of the graph which I hope clarifies this