jafar ebadi

The expected value of a company’s stock can change in response  to new inside and outside information, depending on the nature of the company. The main purpose of this paper is to test the effect of new and different types of information on the bid-ask spread. Accordingly, using with an event study on  a selected sample, we identify release days and specify dummy variables and then we analyze the effect of information on the bid-ask spread with a panel data odel.Other variables include stock return, transaction volume, market return, and the percentage  change in the dollar’s price, oil price, and the average price of precious Metals. Results of the empirical model show that while the new inside information has a positive effect on the liquidity, changes in the outside information lead to a wider bid-ask spread and  lower  stock liquidity. Therefore, outside policy has a negative effect through informational risk and the stability of the outside variable is important for the market’s performance.

It is a fact that “1 Person 1 Vote” is the most common voting system in democracies worldwide. But, when we ask “How about its efficiency in preference revelation?” the answer is “There are lots of other voting systems with more efficiency”. Two of the most recent studies in this field are “Liquid Democracy” and “Quadratic Voting (QV) Mechanism”. By using “Liquid Democracy” voters can delegate their votes to other voters, and by using “Quadratic Voting Mechanism” voters can buy more votes via spending money. This paper’s contribution is combining the two recent studies and designing “Adjusted Quadratic Voting Mechanism”. In fact, this contribution makes it possible to formulize Liquid Democracy and votes’ delegation in the context of Quadratic Voting (QV) Mechanism.

This paper extends an information-based model for an order market with asymmetric information. The new assumption in this expanded model is that possibility of asymmetric influence of changes in inside and outside information. However, other models generally assume that changes in these two types of information have the same value, or focus only on changes in internal information. Therefore, in the new extended model, uninformed traders face informed internal and external traders. In the new equilibrium, when the effect of external information is larger than that of internal information for the stock, in the optimal case uninformed traders choose a lower bid price and a higher ask price as the equality effect of these two types of information, and in the opposite case they choose a higher bid price and a lower ask price.

This paper has investigated the role of search and matching frictions in a monetary model and examined if the Friedman rule, advocating a rate of deflation equal to real interest rate, is still right. We defined a dynamic programming problem in which money is situated in the model by cash in advance constraint, and used a numerical method (value function iteration method) to solve the pre-mentioned problem. Also, in this paper, the concept of the homogenous agent is substituted by the heterogeneous agent, and there are two groups of agents, namely unemployed and employed agents. The difference between the two divergence groups is indicated by different constraints in this study. According to our model, the Friedman rule will not maximize the aggregate welfare of the assumed society with this new friction. It is noteworthy that the parameters of the numerical model have been derived from the United States economy and the essay is theoretical. The results can be applied in different economies with their specific parameters. Also, the study offers some implications to central banks. 

One of the most challenging issues related to the monetary policy is the causes and origins of inflationary shocks and biases. There are two approaches to the monetary policy in general: first, monetary policy based on discretion, and second, monetary policy based on a specific rule. Economists of New Classical School believe that monetary policy should be based on a monetary rule. Accordingly, the cause of inflationary shocks and biases can be considered as a violation of the monetary rule. They believe that economic agents make their expectations rationally. Therefore, an announced monetary policy will not have a real impact and will only cause inflation. As a result, an economists' effort could be to explain the government's motives for violating the monetary rule and to make policy recommendations based on it. This article tries to provide a new solution to the problem of violation of the monetary rule by using a special type of mechanism so called "Clark mechanism" (pivotal or person-centered mechanism) as well as designing micro-bases for the government behavior and rational agents and relying on the issue of government reputation.

The main purpose of this article is to study the transmission of systemic risk from a particular mutual fund to the rest of the mutual funds in Iran Capital Market. Applying the multivariate GARCH model with the Dynamic and constant Conditional Correlation method, we examine the correlation structure of daily net return of the mutual fund portfolios during the period from March 21st, 2011 to March 21nd, 2020. We find the hypothesis of the existence of systemic risk in Iran Capital Market cannot be rejected and the results indicate that the mutual funds are subject to the systemic risk. According to the estimation results of the model, in which Delta δ is significantly positive), it is expected that the conditional correlation among mutual funds to increases following the initial shock in their return series. Also, since the significant Gama coefficient is less than one but very close to it , we could expect long-lasting shocks and persistent uncertainties. The study suggests some managerial solutions for developing a prudential regulation policy to prevent and control systemic risk and to mitigate its effect. Such solution necessitates the establishment of institutions crucial for capital market development, including rating agencies, asset management companies, investment adviser Institutes, and regulation and regulatory agencies as well.

In recent years, higher education in Iran has faced a variety of problems, such as university extra seats, unemployment of graduates, and so on, which cause critical challenges to educational planners and policy makers. Examining main determinants of the applicants’ choice is an important remedy to thses challenges that can be done through developing an appropriate university-discipline choice model. Results derived from such a model, can help educational planners to rectify the challenges and also improve the quality of the applicants’ choices. In other words, understanding the university choice models of applicants helps to understand university choice behavior in Iran and to improve the quality of their university choice, higher education policies, and the decisions of university administrators. In this article, the model of university choice and its determinants in terms of gender, occupation, and residence are designed and estimated using data on the characteristics of a randomly selected sample of participants in the 1397 entrance exam of Electrical Engineering master degrees. The data included information on the field chosen by participants who were allowed to choose the study field and select at least one university-location course. The results of the analyses emplying Rank-ordered logistic model, show a high tendency of the applicants to attend the state universities located in Tehran city and the capitals of Iran’s provinces. Women tend to prefer Tehran more than men and unemployed tend to be significantly more exposed to the daily courses of Tehran city universities.

Optimal resource allocation by means of the price mechanism is one of the main duties of the economics. Optimum allocation is sometimes realized not through the price mechanism, but via assignment algorithms due to an insufficient number of agents on either side of the exchange. Facing the same problem, the kidney market may be considered as a type of market failure that calls for market design. Indeed, such design is regarded as a solution to the problem. Although the current model of organ transplants for non-relative living donors in Iran brings patients certain benefits, it suffers from serious weaknesses that require revisions. The present study aims to analyze the kidney market using a matching theory which is a subset of market design. Then a model is developed in a test market for the research sample in Hamadan Province in 2015. Eventually, recommendations are made to modify the Iranian model of kidney donation. Despite Roth’s model, the proposed model is based on two-sided matching. In this regard, information on 40 kidney suppliers and demanders were recorded in a clearinghouse. Subsequently, agents’ preferences on either side of the market (i.e. patients and donors) were ranked based on blood-type, tissue, duration of disease, age, and gender compatibility. Applying the proposed model to the research sample, the results showed that 19 out of 20 pairs gained access to stable allocations.

In order to analyze the labor market through search and matching theory, we need deep parameters namely, rate of inflow to the unemployment pool and job-finding rate. In other words, these rates are primary parameters of matching function; hence, estimating these parameters is an essential step for the use of search and matching theory in every economy. In this paper, we estimate these rates of Iran’s economy using Simulated Method of Moments (SMM) as a baseline for future studies in this framework. We use the unemployment rate and the number of unemployed workers which were unemployed less than one month. We find estimates of around 0.1 and 0.32 for rate of inflow to unemployment and job-finding rate, respectively, which are lower than the amounts estimated for the United States and other developed countries. This is a sign of some labor market irregularities in Iran economy. For example, it shows that the probability of experiencing long-term unemployment/employment by unemployed/employed ones is high because of lower job-finding and inflow to unemployment rates.

This article determine the monopoly power of 22 food industries among 136 manufacturing industries at 4 digit ISIC level, and also determine the position of food industry in terms of market power dispersion among 23 fields in industry at 2 digit ISIC level. The unstructured and parametric approach of Lu and Yu was used to estimate the monopoly power of industry. According to the results, the mark-up of 73 percent of food industries is more than 10 percent. Industrial production of bread and a variety of beverages are the largest monopoly power, while industries such as production, processing and preserving of meat and meat products; manufacture of vegetable and animal oils and fats; manufacture of dairy products; manufacture of grain mill products show a competitive behavior. On the whole, 87 percent of the Iranian industries have monopoly power and uncompetitive behavior. Meanwhile, the industries have the decreasing average of returns to scale and the position of food industry in terms of inequality rank of market power dispersion, is 12 among 23 industries with 2-digit level. Therefore, using the potential capacity of some industries such as flour production can be helpful, with liberalization the exports of their products while no subsidization is provided for the raw material. In order to increase the competitive nature of the other industries, a strategy can be; reducing and rationalizing the import tariffs with the aim of improving competition.

One of the most critical market duties is to ensure coordination between the supplier and demander. When the market fails to fulfill this duty efficiently, it either does not form or fail and disintegrate. This is because the number of market participants is either too large or too small, and/or the market experiences conditions where the participants scarcely give voice to their priorities with ease and confidence. Economists contend that the fundamental challenge in market design is that we sufficiently understand complex markets and develop our abilities to the point where we can reconstruct or redesign them upon their failure and/or use market-like mechanisms. When the process of price adjustment is slowly at work, economic factors tend to select what they want in the price they observe. Still, many markets are by far beyond this simple economic rule. In such markets, we may not readily obtain what we need even when we can afford it. In other words, while to want to and to be able to (to want a product and to be able to pay for it) generate demand in common markets, these two factors do not necessarily present us as customers in the complex markets since commodities are offered with variable qualities so that it is impossible to form a market for them. Some markets are so complex that people cannot select what they need despite their willingness and ability to pay for it. That is, price mechanism and automatic adjustment do not provide the market with balance although this does not imply the impossibility of market formation. . Market design theory and matching theory seek to provide a stage where suppliers and demanders can meet without using the traditional market mechanism (price mechanism). In this theory, price mechanism does not offer solution to the problem of resource allocation. Rather, allocation is based on suppliers and demanders’ conditions. Based on the proposed algorithm, ranked preferences replace and act as price system. One of the most important applications of market design in the past decade has been to the kidney and body parts market. for the purposes of market design, one should employ an algorithm that can overcome the causes of market failure such as returns to scale, externalities, uncertainty, thinness, congestion and insecurity to demonstrate preferences.These factors affect both market failure and lack of market formation.
The present study aimed to address the problem of kidney market and provide a solution to the problem. Dispersed market participants, limited number of suppliers and demanders, and poor supplier-demander relationshipmay lead to market (kidney exchange mechanism) failure or impede market formation.
In order to resolve this deficiencies we should design a mechanism for overcoming the market failures in order to reach to an efficient and stable allocation. Kidney market is a true example of this type of markets. Therefore, it is suggested to create a clearing room in which the information of kidney donors and patients be recorded and after processing this information and determine patient preferences, the matching algorithm could match the compatible couples(donors and patients)þ and kidney exchange can be facilitated. The present study was carried out in Hamedan Province in 2016 using matching theory which is a subset of market design and mechanism design. To this end, the information for fortyþ people , twenty of them patients and twenty others Kidney donator were recorded in the clearing room. Then, after blood and tissues tests and determining patient preferences and forming matching algorithms, seventeen of twenty patients could receive kidney transplant. However, without using this mechanisms only nine patient could have received transplan, Also using this mechanism will result at least 163817796 Rials per patient.

The aim of this paper is introducing a new method to estimation monopoly power and uses it for 136 Iranian manufacturing industries at 4 digits ISIC level during 2005-2013. The method used is stochastic frontier approach. The results indicate that the markup of nearly 98 percent of manufacturing industries is between 10 and 40 percent and they have an uncompetitive behavior. The average industries markup in Iran had a rising trend over time, reducing their average returns to scale. According to the results; there are suggested canceling the exclusive advantages that used to grant to some industries, lowering the tariff for increasing foreign competition with implementation necessary standards in order to production, importing industerial outputs and expanding industerial activities in the form of cooperatives.

The various types of unemployment have been key subjects of economics from the past periods. Sometimes, unemployment is the result of improper distribution of labor force. According to the statistical data, medical labor market in Iran is faced with such a problem. The density of medical labor in metropolitan areas is high. As a result, this market is of supply surplus. On the other hand, Iran’s towns and suburbs experience demand surplus. This type of unemployment indicates a kind of market failure, which needs to design a market as a solution. Market design as a subset of game theory requires developing through collaborative efforts of a wide range of specialists. In this article, we analyze medical labor market using the matching theory as a subset of market design. This theory is a main subset of market design theory. We apply a hypothetical market; provide a model and present suggestions to amend the medical labor market in Iran.

Despite the relative success of the health system and the promotion of health indicators over the last two decades، Iran''s health system still faces serious problems. One of the most important of them، is the inequity in access to health. Theoretical studies and empirical evidences indicate that implementation of the referral system and family physician plan، is one of the main strategies to overcome inequity in the health and appropriate using of scarce resources in this area. In order to successful execution of the family physician، it is necessary، in addition to reform some known problems، the important factors influencing the decision of participants in the project have been identified by using scientific studies and methods and policy makers develop a package that is designed with maximum compliance to the preferences of the target population in order to increase the likelihood of successful implementation. This study is conducted for this purpose. The results indicate that،the visit،behavior of physician، the time of examination has been spent by doctor and being on call are attributes that influence the decision of citizens to enter to family physician. As we expected، increasing in visit، reduces the willingness to entrance to plan. The respectful behavior that given by the doctors، spending the appropriate time for patients and being On-call، increase the utility of citizens and the probability of their entrance to plan. The willingness to pay for behavior of physician،the time of examination and the attribute of On-call are estimated respectively 9579، 9947 and 3750 Toman.

From a long time ago، predicting of financial crisis has been one of the most important concerns of economists and financial economics experts. In the first section of the present research، based on analyzing the fluctuation of rate of change of 10 Macro. variables during the period of 1358-1391 in Iran''s economy using Static and Dynamic، Variance and Semi Variance، and based on «Self-Organizing Map» neural network model، the exact years of financial crisis in Iran'' economy have been determined. Through the second section، using the «Feed Forward» neural network model، the future value of the rate of change of Macro. variables during 1392-1395 in Iran''s economy have been predicted، and finally via the third section using the «Pattern Net» neural network model and based on results of two previous sections، occurrence of financial crisis in the years of 1392-1395 has been foretold. Based on final results of the present research، it can be indicated that the financial crisis which has been occurred in the year of 1391 in Iran'' economy، which is the consequence of occurrence of financial crisis in1389 and 1390، will be continued in to the year of 1392; however، it will be evaporated gradually during it and the years of 1393 and 1395 are the years without financial crisis; albeit the model is indicating some early warning signals due to the return of crisis to Iran’s economy at the year of 1394.

Today، one of the approaches that in various domains such as health care policy is adopted، is that decision makers in the process of making and implementation of policies، try as far as possible، to consider the preferences and desires of the target population. Therefore، efficient and effective policy design and delivery of health services requires adaptation of their goals to the preferences of the society، which needs knowledge of health policy makers about population’s preferences and their valuation of health programs. Discrete choice experiment (DCE) is one of the best ways to identify the preferences of the population and valuation of outcomes. Because of little knowledge about this approach in iran and limited application of DCE in internal studies especially in the field of health policy، in this paper we emphasis on the reasons of the importance of using a DCE in the health economics and their theorical foundations and applications. We believe that، one of the requirements and prerequisites to successful implementation of the family physician in iran، is the knowledge of policy makers about preferences and desires of participants in this program، i. e. GPs and citizens. Such knowledge، along with other necessary conditions، such as Financing and provision of necessary infrastructure، significantly increases the probability of successful implementation of the scheme.

During previous years, Iran’s economy has been faced with numerous fluctuations, while in some cases it turned to a financial crisis as that of 2011-2012. However, the main question is that whether the financial crisis during 2011-2012 has been similar and predictable based on previous financial crises of Iran’s economy. In the present research, firstly, based on previous studies in the subject of Iran’s financial crises, the years of financial crises in Iran’s economy during years of 1978-2012 were determined. The corresponding results have indicated that three kinds of financial crises including Currency Crises, Money Crises and Twin Crisis (simultaneous Money and Currency Crisis), were occurred in Iran’s economy during 1979-2008. Then the financial crisis periods (in which two or more financial crisis years are included) were determined, the political and economic events during each of them were expressed and the reasons of occurrence of financial crises in each of them were described. Then the data of 10 macroeconomic variables of Iran’s economy belonging to 1978-2012 were deployed. Based on data of 1979-2008 as input data and information about crisis and non-crisis year and special kind of financial crisis in each crisis year as target data, the LVQ model was trained, in order to learn crisis and non-crisis patterns (behavioral patterns of macroeconomic variables in crisis and non-crisis years), and to learn to recognize the various kinds of crisis patterns (to understand which kinds of financial crises has been occurred in each crisis year). Then the trained model (trained model based on data of 1979-2008) was simulated using the data of 10 macroeconomic variables of Iran’s economy during 2008-2012, in order to access the capacity of occurred financial crises of years of 1979-2008 to explain and predict the financial crisis of Iran’s economy during 2011-2012. The results of simulation process indicated that the financial crisis of Iran’s economy during 2011-2012 has had a completely different kind of crisis pattern, compared with those patterns which have occurred in Iran’s economy during 1978-2012.

Given the lack of comprehensive explanation about the factors affecting the fair wage. This paper uses the analytical and descriptive method, explaining the eight components of the labor force characteristics that affect the determination of fair wages. In order to find the priority to those components: interviews with representatives from labor groups, employers, and academic experts were held in Iran. Thus, it became clear that to achieve fair wages, paying attention to all the features of the labor force is necessary. In other words besides the marginal product of labor (which has the third degree of importance), skill level, creativity, level of education as a sign of intelligence, duration of work or experience, seniority and responsibility in the work hierarchy should be taken into consideration as well. It should also be mentioned that workers and employers have different priorities towards each of the above mentioned components. So it is necessary to set up institutional settings to fill the gap between them.

Adopting a policy and deciding on long-term investment in the mining industry by a government or private sector actors depends strongly on the ability to predict the scarcity of mineral reserves. Change in scarcity of mineral reserves is a function of several technological and non-technological factors. Among them, change in technology is the most significant factor affecting scarcity. This paper aims to investigate the relationship between mineral scarcity changes and technological changes. In this study, the effective factors on mineral scarcity were initially considered, and the main and most commonly proposed approaches in the field of scarcity were briefly analysed. The problems associated with these approaches in explaining the relationship between scarcity and changes in technology are then discussed. These approaches are mainly limited to the past available data, whose direction is the development “from scarcity to technological changes”; therefore, they are inefficient in predicting scarcity due to technological changes. To overcome such limitations, a chain technology method was introduced with an approach moving “from technological changes to scarcity”. In this approach, scarcity is firstly explained based on the objective technological changes, and secondly it is related to some technologies affecting scarcity, such as mineral exploration, exploitation, mineral processing, metal production, consumer goods and recycling of scrap metals. The results obtained from this paper can be effectively used to make decisions regarding investment in the mineral industry.

The question of precedence of market economy over democracy (or vice versa) has always been a challenging problem in the domain of political economy. This paper tries to study view points of those advocating the market mechanism precedence to democracy، the proponents of Critical Historical Juncture theory، as well as followers of democracy precedence to market mechanism. The findings of this study show that necessary institutions for a competitive market، especially the property rights، are formed in the transitional process leading to democracy. Therefore، one could not claim that market mechanism precedes the transition to democracy. Meanwhile، the transitional process to democracy is too complicated to be explained merely through the elements of market mechanism.

Given the lack of comprehensive explanation about the effective factors of fair wages and a complete mismatch between Labor Force and employers about that، in this paper with completing the missing loupes in the Akerlof theory «fair wages - effort Hypothesis»، possibility of practical realization of the fair wage on productivity will provided. In this regard، after the theoretical analysis and testing the Akerlof theory، multiple factors affecting the determination of fair wages، through qualitative interviews، and questionnaires completed by representatives from labor & employers groups and academic experts on the labor market، is measured. With using software SPSS17 and EXCEL، constitutive factors of fair wages and the priority of those factors in Iran were tested.

In past decades، economists have focused on human capital and its effect on economic growth and development. In recent decades، attention has been on gender human capital inequality and its role on economic growth. The purpose of this research was to illustrate the effects of human capital inequality in male and female on economic growth in different areas of the world. Utilizing statistic models and econometric، a descriptive- analytic research method was chosen for this study. Statistical population consisted of persons over 15 and 25 years old. Data were analyzed by using human capital Gini coefficient. Result showed that in developing and advanced countries to the extent that human capital inequality in male and female decreases، economic growth increases significantly. An important finding of this study is that decreasing human capital inequality for females has more positive effect on economic growth than males.

Transaction Cost Economics (Williamson, 1985) is a theory of the firm in New Institutional Economics that has been applied for analysing economic transaction; especially, make-or-buy decisions or vertical mergers in firms. The contribution of this paper is applying this theory for a political issue that is party formation. Transaction Cost Economics links the party formation to the transaction costs of politicians in different governance structures. So, two types of governance structures for political activities were considered: partisan and individual structures. Then, the factors affecting the cost of a politician in both structures were studied in three groups: the attributes of political transactions (asset specificity, uncertainty and frequency), formal institutions, and informal institutions. The historical evidences are collected about parties in the United States and Turkey show that political institutions in these countries increased politician's costs in individual structure, and they have no choice besides acting in a party structure. But the evidence of political groups in Iran shows that costs of politicians in the party structure is higher than the individual structure. So in Iran, a party which could manage the government has not been formed yet.

The paper examines for the first time the foreign exchange intervention policy in foreign exchange market of Iran. And in this framework, the study designs and simulates the foreign exchange intervention model in Iran. In the first section, the paper shows that the injection of oil revenues directly to economy and also the absence of potent structure of output are inclusively caused the central bank intervention in the form of foreign exchange buying in the market. This directs to high inflation and low output. So, the survey is designed the foreign exchange intervention model in Iran in the form of nonlinear dynamic continuous-time stochastic model. But because there is no exact numerical solution for the model, the paper presents the Monte Carlo simulated model program base on R package.