It would be nice if research on changing the consumption of animal-based foods estimated not only the changes by type of animal-based food, but also by living conditions. I estimate broiler welfare and cage-free campaigns increase welfare per living time by 92.9 % and 80.4 %. So I think shifting from eating chicken meat from broilers in a conventional scenario to ones in a reformed scenario, and from eating eggs from hens in conventional cages to ones in cage-free aviaries is much better approximated by a 100 % reduction in the consumption of chicken meat and eggs than by no change, which is what may be naively inferred by observing no changes in the consumption of eggs or chicken meat. My sense is that the research is at an early stage, where changes in consumption mostly refer to the total consumption of animal-based foods, or not even this.

I agree, although in many food-service settings other than grocery stores (e.g., restaurants and dining halls), there often are not multiple welfare options within a given animal product. Although overall societal demand could ultimately change the welfare options in those settings, those effects are longer-term and hard to estimate. However, we do have an upcoming project using grocery store data (which I forgot to write about...), and we'll explore whether we have the right data to look at welfare options. Thanks for suggesting! 

Greater uncertainty about whether the lives of farmed animals are positive or negative implies a stronger case for improving their conditions (which is always good) instead of decreasing their population (which decreases welfare if their lives are positive).

Yes, but interpreting the latter part (decreasing total welfare by reducing the population) as bad hinges on total utilitarianism, and would otherwise be interpreted as neutral. If one puts low credence on total utilitarianism, then the possible downside of entrenching CAFOs with net-negative lives (which, as you allude, is bad on pretty much any ethical view) could ultimately outweigh the possibility that having lots of minimally net-positive lives is good (which is true primarily on total utiliarianism). I acknowledge that there is a lot of meta-ethical uncertainty here. The unfalsifiability of it all is so annoying.

Thanks, Vasco!

On the mission statement: Ultimately, yes, our goal is to end farmed animal suffering, and while we are in favor of interventions that improve animal welfare (and I personally am a THL donor), our own research focus is on displacing demand that necessitates CAFOs in the first place. I enjoyed reading your net-positive lives post earlier, and it was a significant update for me. I do, however, think that estimating the threshold between a net-positive and net-negative life seems really hard even for humans (and maybe even for oneself!), let alone other species, so I would be very wary of entrenching CAFOs on the assumption that the lives are net-positive. I am also not personally sold on total utilitarianism, so I am not sure that I want a repugnant-conclusion situation with CAFOs, even if we were certain the lives were minimally net-positive.

On the animal-welfare modeling: What you suggest would be the gold-standard approach, but we need to strike a balance between complexity and comprehensibility/credibility for implementation at Stanford and other universities. We are going to start with much simpler arguments about the total number of animals affected. This is already a big jump, since currently, the university occasionally considers welfare standards (e.g., cage-free) but never the number of animals (hence, much more chicken is now served than in the past to reduce GHG emissions). There are also limitations on the granularity of food procurement data the suppliers give us (e.g., fish species are often unclear). We do plan to do our own sensitivity analyses using more rigorous weights.

Congratulations, Bob! 

Thanks for sharing this candid account of your journey, Seth! How fortunate for the HSF Lab that your path landed you with us. Even though the trip was roundabout, it gave you a breadth and depth of skills, and worldliness, that doesn't come rolled up inside a PhD diploma.

Start by doing work you're invested in, that you're proud of, and people may notice.

This is fantastic advice.

Yes, good point

Agreed, though if their model isn't correctly specified to identify the causal effect on meat (which I agree is tough here), then presumably the effects on plant-based sales would also be suspect.

Good point. This does provide a bit more evidence that it's not just due to other January shocks that were happening regularly before Veganuary started.

There's this in the abstract:

"Average weekly unit sales of plant-based products increased significantly (57 %) during the intervention period (incidence rate ratio (IRR) 1·52 (95 % CI1·51, 1·55)). Plant-based product sales decreased post-intervention but remained 15 % higher than pre-intervention (IRR 1·13 (95 % CI 1·12, 1·14)). There was no significant change in meat sales according to time period. The increase in plant-based product sales was greatest at superstores (58 %), especially those located in below average affluence areas (64 %)."

I think this is pretty bad news, actually.

Here we have an intervention that apparently increases sales of plant-based products by 57% and yet does not decrease sales of meat products at all. Unfortunately, this corroborates a growing body of evidence suggesting that plant-based products often fail to displace meat products, even when they gain their own (orthogonal) market share.

As an aside, even with the effects on plant-based products, it's also hard to attribute causation to Veganuary specifically, since it always occurs during a month that we know is associated with unusual recurring "shocks" (e.g., the end of holiday dinner parties; the beginning of New Year's resolutions).