بررسی رفتار سود حسابداری با استفاده از سری های زمانی باکس - جنکینز

During some past decades, Box Jenkins time-series techniques have been increasingly used to explain, analyze and control tax data in the areas of marketing, production planning, strategic management, finance, captial markets and the like. The same techniques have been applied in the present research to describe the data and examine the behavior of accounting income. The long-range target of the income concept is to attribute “income” to the facts and observations in the real world, being interpreted in two main ways:
1) The capital maintenance concept which is regarded as the most significant by many individuals in that it is endorsed by the Economic Council.
2) The income efficiency concept where the net profit and its related factors are often used as yardsticks to measure the management efficiency.
The third main goal of ‘the income” should be assessed on the basis of its behavioral dimensions. Predictability is one of the behavioral characteristics. The net incomes of several business cycles may be used to make predictions related to the future operations of an enterprise if other factors are within the span of control. Other behavioral characteristics include managerial decision-making, ratio of income variations with the prices of stock exchange and investors’ request for income numbers regardless of the absence of informational contents. Thus the survey of income behavior is of paramount importance in the light of the need felt for the accounting income numbers.
Researches done in this respect have proved that the creation process of companie’s annual income is a moving average (or random walk) of the autoregressive / seasonal income.
The experiments in this research indicate that the creation process of annual income for the Iranian companies is also a moving average. Moreover , the incomes of such companies are lacking in quality, being without rich informational content as to the subsequent incomes. The outcomes gained from intradivisional process aslo hint at the equality of the income creation process in a specific industry.