In microeconomics and demand is an economic model of price determination in a market. It postulates that, holding all else equal, in a competitive market, the unit price for a particular good, or other traded item such as labor or liquid financial assets, will vary until it settles at a point where the quantity demanded will equal the quantity supplied, resulting in an economic equilibrium for price and quantity transacted. Although it is normal to regard the quantity demanded and the quantity supplied as functions of the price of the goods, the standard graphical representation attributed to Alfred Marshall, has price on the vertical axis and quantity on the horizontal axis. Since determinants of supply and demand other than the price of the goods in question are not explicitly represented in the supply-demand diagram, changes in the values of these variables are represented by moving the supply and demand curves. By contrast, responses to changes in the price of the good are represented as movements along unchanged supply and demand curves.

A supply schedule, depicted graphically as a supply curve, is a table that shows the relationship between the price of a good and the quantity supplied by producers. Under the assumption of perfect competition, supply is determined by marginal cost: firms will produce additional output as long as the cost of producing an extra unit is less than the market price they receive. A hike in the cost of raw goods would decrease supply, shifting the supply curve up, while a production cost discount would increase supply, shifting costs down and hurting producers as producer surplus decreases. By its nature, the concept of a supply curve assumes that firms are perfect competitors, having no influence over the market price; this is because each point on the supply curve answers the question, "If this firm is faced with this potential price, how much output will it be willing and able to sell?" If a firm has market power--in violation of the perfect competitor model--its decision on how much output to bring to market influences the market price.

Thus the firm is not "faced with" any given price, the relevant model must become more complex. Economists distinguish between the supply curve of the market supply curve; the market supply curve is the sum of the quantities supplied by all suppliers at each potential price: individual firms' supply curves are added horizontally to obtain the market supply curve. Economists distinguish between the short-run and the long-run market supply curves. Here short run means a constant availability of one or more fixed inputs, a fixed number of firms in the industry. In the long run, firms have a chance to adjust their producing capital, enabling them to better adjust the quantity they supply at any given price. Furthermore, in the long run competitors can enter or exit the industry in response to market conditions. For both of these reasons, long-run market supply curves are flatter than their short-run counterparts; the determinants of supply are: Production costs:. Production costs are the cost of the inputs.

They depend on the technology technological advances. See Productivity. Firms' expectations about future prices Number of suppliers A demand schedule, depicted graphically as a demand curve, represents the amount of a certain good that buyers are willing and able to purchase at various prices, assuming all other determinants of demand are held constant, such as income and preferences, the prices of substitute and complementary goods. According to the law of demand, the demand curve is always downward-sloping, meaning that as the price decreases, consumers will buy more of the good. Just as the supply curve parallels the marginal cost curve, the demand curve parallels marginal utility. Consumers will be willing to buy a given quantity of a good, at a given price, if the marginal utility of additional consumption is equal to the opportunity cost determined by the price, that is, the marginal utility of alternative consumption choices; the demand schedule is defined as the willingness and ability of a consumer to purchase a given product at a certain time.

The demand curve is downward-sloping, but for some goods it is upward-sloping. Two such types of goods have been given definitions and names that are in common use: Veblen goods, which are made more fashionable by a higher price, Giffen goods, which, by virtue of being staples, may see an increase in demand as the price increases; as with the supply curve, by its nature, the concept of a demand curve requires that the purchaser be a perfect competitor—that is, that the purchaser have no influence over the market price. This is true because each point on the demand curve answers the question, "If buyers are faced with this potential price, how much of the product will they purchase?" But, if buyers--in violation of the perfect competitor model--are seen as having market power, their buying decisions influence the market price. Buyers are not "faced with" any given price, the model becomes much more complicated; as with supply curves, economists distinguish between the demand curve for an individual and the demand curve for a market.

The market demand curve is obtained by averaging the sum of the demand of all consumers at each potential price. The determinants of demand are: Income. Tastes and preferences. Prices of related goods and services. Consumers' expectations about future prices and incomes that can be checked. Number of potential consumers. Speaking, an equilibrium is defined to be the price-quanti

Andrea Lussardi is a former Italian footballer who played as a winger. Born in Lodi, Lussardi started his career at Emilia–Romagna club Piacenza. Lussardi got scholarship for his good academic result as a football trainee. A month after his national U18 debut, Piacenza decided to sell him. On 30 June 2010, the last day of 2009–10 financial year, Lussardi along with Italy U16 internationals Matteo Colombi were sold to F. C. Internazionale Milano in co-ownership deal for a total fee of €1.5 million, in five-year contract. In exchange, former youth internationals Andrea Mei and Luca Tremolada was signed by Piacenza first team in co-ownership deal for €1.5 million. Lussardi had played for Inter in 2010 Trofeo Dossena, losing to Lega Pro U20 representative team in the semi-finals on 16 June 2010. Lussardi made 14 starts for the under-20 team in the Primavera league without a goal; the team had Simone Dell'Agnello as centre forward and Denis Alibec and Mame Baba Thiam as forward in 4–3–3 formation. Coach Fulvio Pea had tested several players to partner with Dell'Agnello.

Lussardi won 2011 Torneo di Viareggio as unused bench in the final. In the playoffs round of the league and the coaching team rested two of the three senior players of the reserve and Davide Faraoni in order to train the younger players. Lussardi played both first round and second round as starting wing forward in 4–3–3 and 4–4–2 formation, losing to Milan after penalty shootout. In June 2011 Piacenza decided not to renew Mei and Tremolada's co-ownership, as they were not the regular in 2010–11 Serie B as well as the relegation of the club, thus not economical to give chance to the two players to play as a process of player development Co-currently, Internazionale sold back Lussardi and Colombi but renewed the loan of the latter, as part of compensation and youth plan; the four players were priced for the original estimate, which the 50% registration rights were: Mei €750,000, Tremolada €750,000, Lussardi €900,000, Colombi €600,000, thus again did not involved cash. Lussardi returned to Piacenza and was a member of the first team and a overage player of the reserve in Berretti League.

He played twice in 2011–12 Coppa Italia. Lussardi was one of the attacking midfielder in 4–2–3–1 formation. However, he was missed a few months. Lussardi made his debut in 2011–12 Lega Pro Prima Divisione on 4 April 2012, after the club was declared bankruptcy by the court, with Lussardi and Colombi became a financial burden for the club with impaired performance. Lussardi substituted Francesco Lisi in that match, he made his first start on 25 April, after the last match of the reserve league on 21 April. In June 2012 no investor wished to takeover the shares of Piacenza for just €50,000, thus Piacenza did not apply to enter professional league and folded; as FIGC did not forced players to have any obligation to sign a new contract with the new club formed in the same city, thus Lussardi would become a free agent and the indebtedness of the club would further damaged by the write-off of the high accounting value of Lussardi and Colombi. On 7 July 2012, Serie B club Reggina signed Lussardi while Colombi joined Internazionale definitively.

On 9 August 2012, he moved to Pavia on a loan deal. In June 2013 the club excised the option to sign him in co-ownership deal. In November 2013 he retired from professional football. Lussardi received a call-up from Italy national under-17 football team in 2008; however Lussardi did not enter the squad to the elite qualification. In February 2010 Lussardi received a call-up from Italy national under-18 football team for a training camp, but did not go to 2010 Slovakia Cup either in April. In May 2010 Lussardi made his debut against Belarus, he substituted Francesco Finocchio at half time. Lussardi played twice for Italy national under-19 football team in 2010–11 season, replacing Simone Verdi, in two of the six friendlies between the qualification and the elite qualification. FIGC Profile at worldfootball.net

Bury Knowsley Street is a former railway station in Bury. The station was first opened by the Lancashire and Yorkshire Railway on 1 May 1848 being named Bury. Services ran east west to Bolton and Wigan Wallgate. There was a connection from here northwards to neighbouring Bolton Street station on the East Lancashire Railway line from Clifton Junction to Bacup & Accrington; the station was renamed twice: to Bury Market Place in February 1866, to Bury Knowsley Street in 1888. The line and station were closed on 5 October 1970 as part of continuing cutbacks in British Rail services and the line west to Bolton subsequently dismantled. On 19 January 1952, the station footbridge collapsed under the weight of a large crowd entering the station following a football match. Two people were killed and 173 injured when the metal struts supporting the bridge's footway failed. No trains were in the station at the time; the accident report determined that while the bridge's design was adequate, it had been inadequately maintained and the metal struts which failed had certainly required replacement for 10 or 15 years prior to the accident.

There is no physical trace of the disused platforms. The line from Bury Bolton Street to Heywood through the station site was reopened in 2003 by the East Lancashire Railway; this had stayed open to freight until December 1980 and had crossed what is now the Manchester Metrolink line to Bury Interchange on the level. In order to reopen the route, a bridge was constructed in the early 1990s & opened to traffic in July 2003 to carry the ELR line over the Metrolink and this now occupies the old station site; the route towards Bolton is now overgrown & derelict and has been blocked at Bradley Fold by a housing development. Railscot - Photos of Bury Knowsley Street