Posted on January 6, by Scott Alexander [Epistemic status:
Positive and Negative Feedback: They are equilibrium systems. What does that mean? Transportation costs both time and money. These costs are represented by a supply curve, which rises with the amount of travel demanded. As described above, demand e. These two curves intersect at an equilibrium point.
Time is usually converted to money using a Value of Timeto simplify the analysis.
It means the system is subject to a negative feedback process: An increase in A begets a decrease in B. An increase B begets an increase in A. Positive feedback loop virtuous circle Positive feedback loop vicious circle However, many elements of the transportation system do not necessarily generate an equilibrium.
Take the case where an increase in A begets an increase in B.
An increase in B begets an increase in A. This example assumes the gas tax generates more demand from the resultant road building than costs in sensitivity of demand to the price, i.
This is dubbed a positive feedback system, and in some contexts a "Virtuous Circle", where the "virtue" is a value judgment that depends on your perspective. Similarly, one might have a "Vicious Circle" where a decrease in A begets a decrease in B and a decrease in B begets a decrease in A.
Again "vicious" is a value judgment.
Less service results in fewer transit riders, fewer transit riders cannot make as a great a claim on transportation resources, leading to more service cutbacks.
These systems of course interact: One might ask whether positive feedback systems converge or diverge. The answer is "it depends on the system", and in particular where or when in the system you observe.
There might be some point where no matter how many additional roads you built, there would be no more traffic demand, as everyone already consumes as much travel as they want to.
We have yet to reach that point for roads, but on the other hand, we have for lots of goods. If you live in most parts of the United States, the price of water at your house probably does not affect how much you drink, and a lower price for tap water would not increase your rate of ingestion.
You might use substitutes if their prices were lower or tap water were costliere. Price might affect other behaviors such as lawn watering and car washing though. Examples of Feedback Systems[ edit ] We explore a few examples related to urban growth, accessibility, electric vehicle adoption, and urban transit.
More congestion limits demand, but more demand creates more congestion. Buses operating with high frequency tend to bunch.Positive Externality. A positive externality exists when an individual or firm making a decision does not receive the full benefit of the decision.
The benefit to the individual or firm is . There is a growing debate about whether people should leave Facebook and whether there should be government regulation.I’d like to argue that it is very difficult for most people to leave Facebook three reasons: network externalities, social norms and technical competence.
BETTER BUSINESS BETTER WORLD The report of the Business & Sustainable Development Commission January A comprehensive review of positive psychology. Positive psychology. William D. Tillier; Calgary Alberta; Update: Under construction.
An environmental impact statement (EIS), under United States environmental law, is a document required by the National Environmental Policy Act (NEPA) for certain actions "significantly affecting the quality of the human environment". An EIS is a tool for decision making. It describes the positive and negative environmental effects of a proposed action, and it usually also lists one or more.
Remember, an externality is a cost or benefit incurred by a party due to the decision or purchase of another, who neither obtains the consent of the said party, nor effectively considers the costs and/or benefits to the said party in the decision. An environmental impact statement (EIS), under United States environmental law, is a document required by the National Environmental Policy Act (NEPA) for certain actions "significantly affecting the quality of the human environment". An EIS is a tool for decision making. It describes the positive and negative environmental effects of a proposed action, and it usually also lists one or more. Human Industrial Activities In the United States, as is the case in most industrialized nations, the greatest source of pollution is the industrial community.
[This is a repost of the Non-Libertarian FAQ (aka “Why I Hate Your Freedom”), which I wrote about five years ago and which used to be hosted on my website.