What factors determine the magnitude of the price elasticity of demand?

What will be an ideal response?

There factors determine the magnitude of the elasticity of demand: the closeness of substitutes, the time elapsed since a price change, and the proportion of income spent on the good. The more substitutes for a good, the more elastic its demand. For instance, luxuries have more substitutes than necessities, and so the elasticity of demand for luxuries exceeds that for necessities; and, narrowly defined goods have more substitutes than broadly defined goods, and so the elasticity of demand for narrowly defined goods exceeds that for broadly defined goods. The more time that has elapsed since a price change, the more substitutes consumers can find, so the elasticity of demand is larger the more time passes. Finally, the larger the fraction of consumers' income spent on a good, the larger is its elasticity of demand.