In a structural time series regression model, binary variables have been used to quantify qualitative or categorical quantitative events such as politic and economic structural breaks, regions, age groups and etc. The use of the binary dummy variables is not reasonable because the effect of an event decreases (increases) gradually over time not at once. The simple and basic idea in this paper i...

abstract the present research accomplished to determination of the trade liberalization effects on import function of iran’s wheat crop using time series data from 1357 to 1387 that earn from sources such as agricultural and aerology statistics annual letter, customhouse and iran central bank website.in this investigation, at first, wheat liberalization index was measured by using level of inte...

We test for fractional dynamics in CPI-based inflation rates for twenty-seven countries and WPI-based inflation rates for twenty-two countries. The fractional differencing parameter is estimated using semiparametric and approximate maximum likelihood methods. Significant evidence of fractional dynamics with long-memory features is found in both CPIand WPI-based inflation rates for industrial as...

one of the most important variables in each country which attracts the attention of policymakers is inflation. in the inflation targeted system, it is important to target the low and stable inflation clearly and directly as the main policy. on the other hand the stability of prices which is an important result of targeted inflation is a necessary condition to achieve sustainable levels of econo...

This paper introduces a new model of trend inflation. In contrast to many earlier approaches, which allow for trend inflation to evolve according to a random walk, ours is a bounded model which ensures that trend inflation is constrained to lie in an interval. The bounds of this interval can either be fixed or estimated from the data. Our model also allows for a time-varying degree of persisten...

In this paper, Economic Order Quantity ( ) based model for non-instantaneous deteriorating items with imperfect quality, permissible delay in payments and inflation is proposed. We adopt a time-dependent demand function. Also, the effects of time value of money are studied using the Discounted Cash Flow approach. Moreover, we assume that orders may contain a random proportion of defective items...

a r t i c l e i n f o Economic production quantity (EPQ) is the quantity of a product that should be manufactured in a single batch so as to minimize the total cost. In classical model EPQ only applies where the demand for a product and production rate is constant over the year. But in reality these parameters vary with time in different scenarios. In this paper we have considered a production ...