Geez, at least give me a chance before you decide what I can't do.

The difference is pretty basic: Having a "negative impact" requires value-judgement, having a cost does not. In terms of economics it requires a broad view of the entire economy, whereas a cost can be directly assigned to a single event or series of events.

Saying that a regulation has a cost is saying that it requires some expenditure to implement/maintain. Saying it has a negative impact is saying that the expenditure to implement/maintain that regulation outweighs the as-yet-in-this-discussion undefined benefits of the regulation in question.

You have not demonstrated a net negative cost. In fact, I wonder if you even read the abstract, which states in pertinent part: [Authors] find that previous estimates of the costs of economic regulation probably overstated the true costs by failing to distinguish between transfer payments and net changes in economic efficiency [...] Overall, they find that the efficiency cost due to economic regulation is large and that the benefit from social regulation is positive but small. Their study also finds a huge variation in estimates of the costs and benefits ofparticular regulatory policies, particularly in the transportation sector and in environmental protection. This variation indicates that most estimates may be merely "guesstimates."

Going with your random example plucked from the article... [Milk market regulations] cost US citizens somewhere between $500 million and $2.1 billion per year - in 1991.

Besides the wild variation, so what? That number is meaningless without the context of the size of the milk market as a whole which would allow us to assess the scope of the burden, not to mention some estimate of the likely economic cost of an unregulated milk marketplace (eg economic losses due to illness from disease).

Why do you think it's impressive to pull out a big number like this without any context? It's ridiculous. If we're going to go with cherry-picking argument of this type, I can't help noticing that Americans love milk and almost every American refrigerator I'e ever seen has an open container of milk. So since we're talking about the US as a whole in your example, and there were ~250m Americans in 1991, it seems like these regulations imposed a cost of between $2 and $8 that year on every American...which doesn't sound like all that much to pay for a year of knowing the milk you enjoy is safe to consume. MY household spends about $7-800 a year on dairy products, so back in 1991, and adjusting very generously for inflation, we might have spent $200 to consume the same amount of milk. Using the worst-case number from your paper, positing an upper regulatory burden for every American of $8 and doubling it to represent the two people in my household, maybe $16 of that $200 consisted of regulatory costs. So the worst-case scenario is that regulation drove up the cost of milk by 8%, which doesn't sound like that bad of a trade.

Since I've done all the work here so far perhaps you'd like to estimate the benefits of reliably safe milk in terms of avoided medical costs from dairy-borne pathogens.

>Why did you feel the need to reply with this sentence? How does it advance our conversation whatsoever?

Because you replied with a link to something that did not further the point under discussion.

>Is a large cost not a large negative impact?

No, it is not.

>The journal article I linked is literally about the large, economy-wide costs of regulations.

And it appears to mostly disagree with the point you are trying to make.