ارتباط انحنا و قیمت کالای مستهلک

Introduction

In a vast sense, economy is a medium of products distribution and exchange of goods or services by different agents. Demand and supply issues for goods and services lead societies to plan market-based economics. The main goal of market-based economics is to balance demand and supply, known as the general equilibrium. Mathematical economy paves the way to verify the existence, uniqueness, and algorithms for computing the equilibria. Differential geometries prefer to visualize the shape of the equilibrium manifold, i.e., the set of pairs of prices and endowments such that the aggregate excess demand function is equal to zero. Balasko had shown if the equilibrium price is unique for every economy, the price is constant, and the curvature is zero. Moreover, Loi and Matta generalized it in the form that for two commodities and an arbitrary number of agents, if the curvature of E(r) , which is equilibrium manifold with fixed total resources r , is zero, there is the uniqueness of equilibrium for every economy.

The general equilibrium condition is also must be held in a flea market, in which all kinds of goods are in their depreciated form. By definition, depreciation is the decline in the value of an asset over time due to different factors such as usage, wear, and tear and obsolescence, which is a significant concept that must be considered when pricing an item for sale. One reason why depreciation must be considered is that, if it is not, businesses would have an unrealistic and distorted estimation of their assets. Consequently, their estimation of the depreciation period net profit in the book value (B.V) will be inaccurate. In turn, the amount of tax a company needs to pay may exceed the original amount as the losses are not considered accurately. Here, to calculate the incurred losses due to depreciation, we consider the current value of the original price paid for the item, considering the interest rate and different depreciation periods. This matter yields the current value of the item to be sold and, comparing it with the current value of its original price lets us understand whether selling the price is to the benefit of the seller or not.