You are right that my use of the word 'probability' for the yellow line was a bit misleading. 1% decrease in the yellow line could mean either

• 1% chance that there is no more animal farming because of an x-risk or something
• 1% reduction in meat production due to alt proteins

I should say though that based on my conversations at the time, it seemed unlikely that alt proteins will make a big difference.

The section Invertebrates in the article documents some studies that suggest that invertebrates are not directly affected by noise, unless the source is less than a meter away

Even though I expressed some scepticism about wild animal welfare work in the past, I am excited about this initiative. I'd consider donating to it if I was in a position to donate.

Wow, I was about to write a similar comment, but you said it much better than I would have.

I just have a question about the “farms that operate at 80% full capacity.” Are you sure there are many such farms? I’d imagine most operate on thin margins, so it would be unusual for them to have unused sheds or significant spare capacity without a good reason. That said, Vasco listed other ways farmers could increase supply to meet demand quickly without building new farms in this comment. For what it’s worth, LLMs seem to disagree about how important such effects are.

To me, perhaps a bigger issue is anticipation. Once investors know that new farms face a high risk of being blocked or delayed by protests, they may (a) decide not to build farms at all (but someone else might build them instead), (b) shift their plans to other countries where protests are less likely, or (c) submit more planning applications than they really need, expecting some to be blocked. And if investors in other countries see a disruption in UK supply, they might also respond by building more farms abroad. If that’s true, the first few farms blocked might have much more impact than those blocked later, once the market has adjusted to the likelihood of farm-blocking efforts.

This is great, thanks for writing this. It gave me some clarity about something I’ve been confused about for a long time.

Btw, another effect to consider is anticipation. Investors in Poland already know that new farms face a high risk of being blocked or delayed by protests. Given this, they may (a) decide not to build farms at all (but someone else might build them instead), (b) shift their plans to other countries where protests are less likely, or (c) submit more applications than they really need, expecting some to be blocked. Since the campaign has been active for years, it’s possible the market has already adapted to the reality that building new farms in Poland is unusually difficult, and has found alternative ways to meet the demand.

No, I did not think about the effects you listed when choosing these numbers, at least not explicitly. I don’t remember what exactly went through my head when I imputed these numbers. I think I was just trying to imagine what a chicken production graph would look like with or without campaign. Naively thinking, blocking a farm would postpone the production by at least 1-2 years, because that’s how long it probably takes to get planning permits and build a farm. But 1-2 years felt like too optimistic though, so I was conservative, but probably not conservative enough.

Either way, those figures of years of impact are guesses in the spirit of If It's Worth Doing, It's Worth Doing With Made-Up Statistics, not estimates. I was supposed to finish the project and had no idea how to estimate these things, so I entered somewhat random numbers. Please don't take them seriously. I think you would be much better off ignoring them, and coming up with a new estimate from scratch. Clearly you are thinking about this much more deeply than I was.

I am taking a break from research and I won't try to understand what you wrote here because it's currently over my head and that's not the type of thing I want to focus on right now in life. You can talk with Jakub Stencel if you are interested on improving my estimates, he would tell you whether it's worth it (he is on the forum you can just tag him). But you might also need to talk to someone who say works on the stop the farms campaign for some context. They say that there will be protests against new farms no matter where they are built within Poland because of the network Anima created, but in most other countries it's not happening. To me the bigger question is if the campaign is even net-positive, because it might just shift production to countries where it's more difficult to improve conditions for farmed animals.

Some random thoughts about your message:
* I did look into elasticities during my project and other elasticities of chicken can be found in this very old ACE spreadsheet and in this paper which analyzes elasticity some years ago in Turkey and says “According to the supply and demand functions for chicken meat, supply elasticity is 0.377 and demand elasticity is 0.030”. I remember comparing the two and getting wildly different numbers.
* I will say that tI still don't understand what you mean that "the reduction in the demand/supply of chicken meat is 16.7 % (= (1 - 0.76)*0.695) of the annual production of the targeted farms." I mean, if we say closed a farm of a million broilers, in the very short term at least, surely the reduction of the number of broilers farmed in the world is one million. It's not like those other chickens instantly appear somewhere else. So to me the question is still how quickly market goes back to equilibrium. Your variable Delta_t_S and my guess of 0.695 years of impact seem like two different things by the way. Maybe the reduction in production for a closed farm is 16.7% × "the lifetime of a farm"? Plus a bit more because it would take the market some time to adjust?

I saw cumulative elasticity factor being used for impact estimations of veganism. I get it: if some people stop buying chicken, and now only 900 are sold at $1, the price might drop to $0.9. Then the question of how much production contracts is where elasticities come in. But with production shifts it feels different, messier. If we assumed that vegans would start eating chicken again once the price falls, then even the veganism case would be just as confusing.

Thanks Vasco. I still don’t see how such a multiplier would solve the core issue for me. Say a chicken costs $1 and 1,000 of them are produced and sold. Market is at equilibrium. We close down a farm, and now 900 are produced and sold, and the price goes up. The real question for me is how quickly the market adjusts back—how soon someone else builds another farm to fill that gap. I have no idea. I’ve never seen an economic metric that directly measures that speed of recovery. If an economist were to estimate it, I imagine elasticities would be part of the picture, but I don’t know how that estimate would actually look. So at this point, I’d rather not introduce a multiplier that might confuse me and readers without solving the problem I’m trying to get at.