price elasticity, income elasticity and cross elasticity of demand chapter 8 Flashcards
(36 cards)
elasticity
numerical measure of responsiveness of one variable following a change in another variable, ceteris paribus or other things equal.
elastic
where the relative change in the quantity demanded is greater than the change in price, income or the prices of substitutes and complements.
inelastic
where the relative change in the quantity demanded is less than the change in price, income or the prices of substitutes and complements.
why is the distinction between elastic and inelastic important
The distinction is important as it can be used to explain how firms respond to a range of changing circumstances in their markets. These circumstances include understanding how much the quantity demanded for a good or product responds not only to a change in its price but also to a change in the income of consumers or the prices of substitutes and complements.
Price elasticity of demand
measures of the responsiveness of the quantity demanded for a product following a change in the price of the product. PED=%change in demand/%change in price. negative figure is because of the negative (or inverse) relationship between price and quantity demanded; as the price goes up, the quantity demanded goes down and as the price decreases, the quantity demanded increases. (Economists usually refer to PED in absolute terms by ignoring the negative sign)..
price elastic
when the relative change in the quantity demanded is greater than the change in price of the product.
price inelastic
when the relative change in quantity demanded is less than the change in price of the product.
perfectly inelastic
where a change in price has no effect on the quantity demanded. when the PED =0, demand is perfectly inelastic.
perfectly elastic
where all that is produced is sold at a given price. the relative change in quantity demanded is infinite, since the original demand was zero.
unit elasticity
where the change in price is relatively the same as the change in quantity demanded. demand is said to be perfectly inelastic when the ped= -1.
factors affecting price elasticity of demand
the availability and attractiveness of substitutes
the relative expense of the product
the time period such as short run or long run
how the availability and attractiveness of substitutes affects elasticity of demand
The greater the number of substitute products and the more closely substitutable those products are, the more it can be expected that consumers will switch away from a particular product when its price goes up (or towards that product if its price falls). As we classify products into groupings demand will start to become more price inelastic. So, the narrower the definition of the market, the likelihood is that the PED will be greater.
how the relative expense of the product affects elasticity of demand
A rise in price reduces the purchasing power of a person’s income and their ability to pay for products. The larger the proportion of income that price represents, the larger the impact is on the consumer’s income as a result of a change in the product’s price. So, the greater the relative proportion of income accounted for by the product, the higher the PED.
how the time period such as short run or long run affects elasticity of demand
In the short run, perhaps weeks or months, people may find it hard to change their spending patterns. In the longer run, if the price of a product goes up and stays up, then over time people will find ways of adapting and adjusting, so the PED of a product is likely to increase over time. In other words, it changes from being price inelastic to price elastic as consumers look at what else is available in the market.
substitutability issues
The quality and extent to which information is available about products that consumers need so as to be able to satisfy their particular wants and needs.
The extent to which people consider the product to be a necessity or a luxury. Necessity goods are essential for everyday living and are price inelastic. Luxury goods are price elastic as consumers can do without them.
The addictive properties of the product (whether the product is habit-forming). Their demand is likely to be price inelastic.
The brand image of the product. Such products are likely to be price inelastic.
PED and downward sloping linear demand curve
PED is not the same throughout the entire length of the demand curve. PED is calculated using percentages. When prices are high and the quantity demanded is low, a large change in price will not be a large percentage change; the percentage change in quantity demanded will be higher and significant in percentage terms. This results in demand being price elastic. on the upper part of the demand curve. The reverse applies and explains why PED is inelastic in the lower portion of the demand curve.
income elasticity of demand (YED)
measures the responsiveness of the quantity demanded for a product following a change in income. YED= %change in quantity demanded/%change in income. measures how the quantity demanded is affected by a change in a consumer’s income.
change in income elasticity of demand
If demand is responsive to an income change, the percentage change in quantity demanded will be greater than the percentage change in income. This produces an income elastic outcome and a YED which is greater than 1. Where demand is not responsive to an income change, then the quantity demanded is income inelastic and has a value of less than 1.
the classification of goods in relation to income
this classification is based on the size(in numerical terms) and the sign(positive or negative). the four
The classification of goods in relation to income depends on the level of income of consumers or households.
types of goods that can be identified using YED-
normal goods
inferior goods
necessity good
superior or luxury good
how are normal goods identified using YED
A normal good is one where the quantity demanded increases as income increases. For normal goods, the YED is positive and expected to be between 0 and 1.
how are inferior goods identified using YED
An inferior good is one where the quantity demanded decreases as income increases or increases as income falls. In the case of a rise in income, consumers use their increased incomes to buy better quality goods to replace inferior substitutes. The YED is negative; its size indicates the strength of the relationship between a change in income and the quantity demanded.
how are necessity goods identified using YED
A necessity good is a type of normal good for which the quantity demanded is unlikely to change when income changes. The YED is positive but is likely to be close to zero. A low value for the YED indicates that there is a limit to the quantity of these goods that households purchase even when the change in income might seem to be substantial.
how are superior goods identified using YED
A superior or luxury good has a positive YED that is greater than 1 and is a normal good where the quantity demanded is responsive to changes in income. The higher the size of the YED, the greater the change in quantity demanded.
necessity good
a type of normal good with a YED that is close to zero.