Law of demandIn microeconomics, the law of demand is a fundamental principle which states that there is an inverse relationship between price and quantity demanded. In other words, "conditional on all else being equal, as the price of a good increases (↑), quantity demanded will decrease (↓); conversely, as the price of a good decreases (↓), quantity demanded will increase (↑)". Alfred Marshall worded this as: "When we say that a person's demand for anything increases, we mean that he will buy more of it than he would before at the same price, and that he will buy as much of it as before at a higher price".
Price elasticity of demandA good's price elasticity of demand (, PED) is a measure of how sensitive the quantity demanded is to its price. When the price rises, quantity demanded falls for almost any good, but it falls more for some than for others. The price elasticity gives the percentage change in quantity demanded when there is a one percent increase in price, holding everything else constant. If the elasticity is −2, that means a one percent price rise leads to a two percent decline in quantity demanded.
Demand curveIn a demand schedule, a demand curve is a graph depicting the relationship between the price of a certain commodity (the y-axis) and the quantity of that commodity that is demanded at that price (the x-axis). Demand curves can be used either for the price-quantity relationship for an individual consumer (an individual demand curve), or for all consumers in a particular market (a market demand curve). It is generally assumed that demand curves slope down, as shown in the adjacent image.
DemandIn economics, demand is the quantity of a good that consumers are willing and able to purchase at various prices during a given time. The relationship between price and quantity demand is also called the demand curve. Demand for a specific item is a function of an item's perceived necessity, price, perceived quality, convenience, available alternatives, purchasers' disposable income and tastes, and many other options. Innumerable factors and circumstances affect a consumer's willingness or to buy a good.
Inferior goodIn economics, an inferior good is a good whose demand decreases when consumer income rises (or demand increases when consumer income decreases), unlike normal goods, for which the opposite is observed. Normal goods are those goods for which the demand rises as consumer income rises. Inferiority, in this sense, is an observable fact relating to affordability rather than a statement about the quality of the good.
Cross elasticity of demandIn economics, the cross (or cross-price) elasticity of demand measures the effect of changes in the price of one good on the quantity demanded of another good. This reflects the fact that the quantity demanded of good is dependent on not only its own price (price elasticity of demand) but also the price of other "related" good. The cross elasticity of demand is calculated as the ratio between the percentage change of the quantity demanded for a good and the percentage change in the price of another good, ceteris paribus:The sign of the cross elasticity indicates the relationship between two goods.
Bien (économie)vignette|Diada de Sant Jordi en 2007. Défilés pour la vente de Livres. Un bien est une chose utilisable pour combler un besoin fondamental ou un désir. Entendu le plus souvent comme étant une chose concrète et physiquement tangible, il se différencie du service qui par opposition est dit « intangible ». Cependant, en microéconomie, la notion de bien peut recouvrir les deux notions de bien et de service. Un bien peut faire l'objet d'un usage ou d'une appropriation par un individu ou une collectivité.
Effet VeblenL’effet Veblen, ou effet de snobisme, a été mis en évidence par l’économiste et sociologue Thorstein Veblen, dans son ouvrage Théorie de la classe de loisir (1899). Dans le domaine des biens de luxe ou du moins ceux qui permettent une certaine distinction sociale, la baisse de prix de ces produits se traduit par une baisse de l'intérêt qu'ils présentent aux yeux de leurs acheteurs potentiels. De manière inverse, la hausse du prix d'un produit peut le rendre davantage désirable et le faire entrer dans la catégorie des biens dont la possession traduit un rang social élevé.
Substitute goodIn microeconomics, two goods are substitutes if the products could be used for the same purpose by the consumers. That is, a consumer perceives both goods as similar or comparable, so that having more of one good causes the consumer to desire less of the other good. Contrary to complementary goods and independent goods, substitute goods may replace each other in use due to changing economic conditions. An example of substitute goods is Coca-Cola and Pepsi; the interchangeable aspect of these goods is due to the similarity of the purpose they serve, i.
Offre et demandeL'offre et la demande est un modèle économique de détermination des prix dans un marché. Notamment utilisé en microéconomie, ce modèle énonce que, certaines hypothèses étant respectées, le fonctionnement d'un marché permet au prix unitaire du bien vendu sur ce marché de varier jusqu'à ce que où la quantité demandée soit égale à la quantité fournie. Il résulte ainsi un équilibre économique entre le prix offert et la quantité demandée.
