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Abstract
Aims: By 1404, Tehran will be a knowledge-based, smart, and global city. Having the proper infrastructure and consequently a metropolis with national and global functions with a modern economy are its other features. The global experience of metropolises management shows that optimal urban management requires comprehensive attention to the city's economic, social, and environmental structures, and this has been measured in recent decades, globally, by the urban competitiveness index. Therefore, the present study was conducted with the aim of evaluating the urban competitiveness and Tehran’s status among the metropolises of Iran.
Instruments and Methods: The present study is an applied and survey research that was conducted in 2011. Eleven variables were selected as economic indices of urban competitiveness such as unemployment rate, economic participation rate, etc., by the library method and from three official sources of the country: statistical yearbooks of the provinces, results of census of industrial workshops with 10 employees and more, published by the Statistical Center of Iran and statistics of Ministry of Cooperatives, Labor, and Social Welfare. Standardized score and numerical taxonomy were used.
Findings: Tehran metropolis ranked first in terms of urban competitiveness index and economic aspect. Tehran was the first metropolis of Iran with a score of 3.13 in terms of the urban competitiveness index in standardized score method and 0.72 in numerical taxonomy.
Conclusion: Although Tehran does not have a good status in terms of the urban competitiveness index compared to other metropolises in the world, it ranked first in this index among Iranian metropolises.
 

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Entrance of new firms in the industry, according to existing theories, prepares the ground for competition, evolution, growth and innovation that can potentially lead to growth and economic development. This will come true only if the new firms have the ability to survive in economic activity for a reasonable time and are not forced out of the industry in the early years of their entrance. Several reasons have been studied for the exit of industrial firms in the literature of industrial economics. It is believed that the level of industrial technology used by the firm at the early stage of its activities is the main and effective factor that determines the exit time of the firm. This paper is aiming at examining the effects of technology level on exit probability of the new firms in industrial economy of Iran during the years 2001 to 2005. Data of manufacturing firms is extracted from the censuses conducted by the Statistical Center of Iran and the technology level is determined according to OECD classification. Cox hazard model is used in this study to determine the exit probability. The results of this study show that the technology level of industry has had a meaningfully negative impact on the exit probability of new firms. In other words, the firms entering the industry with medium-and high-technology level have a lower probability of exit.  

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Although many firms enter into the market in completely different sizes, recent facts show that the size distribution of new-entrant firms tend to more homogeneity than disparity over time. This is known as industrial dynamics in the literature of industrial economics. The dominant view in this area is learning by doing, in which firms can enter into an activity at any sizes. However, they will learn over time that which size of the market is effective enough to enable them to remain in the market in the long run to give them the chance to adjust their size. Meanwhile, firms that failed to learn it in a reasonable time will have to exit the market. Therefore, the most significant objective of this paper is to review the way of size distribution in firms in arrival time and its adjustment over time in Iran that is not so far taken into consideration well. This subject can have prestigious application for new-entrant firms as well as increasing their lifetime in the market by decreasing adjustment time for incumbent firms. A descriptive-analytical method has been applied for doing this research. The industrial firm data collected by Statistical Center of Iran (SCI) in ten consecutive years are also used for this purpose. The results indicate that the average size of new-entrant firms is smaller than that of incumbent ones. In other words, manufacturing firms in Iran are born smaller in size in comparison with incumbent firms. Additionally, broad size dispersion of the firms at arrival decline during the learning by doing in most industries and tend to more homogenous size distribution. The results have also revealed that although in most selected industries the average size of new entrants has been increased, the intensity of increase is separable in three groups: 1. firms smaller than industry average, 2. firms with close size to the average industry size and 3. firms larger than industry average. Average growth of firm size located in the middle range (group 2) is about half of this measure toward group 1. However, average growth of firm size located in larger groups (group 3) is about half of this measure toward the group 2. This subject as the most essential findings of the industrial dynamics in the economy of Iran indicate that -unlike the usual- small and medium criterion could be modified to suit the type of industry or be influenced by time. Finally, the findings of this research imply that applying absolute definition for a variable conception (small, medium and large firms) cannot be considered rational.

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Entering firms into a business can be a sign of economic dynamism, but to what extent do they enter according to optimal size or converge to it? The answers are given in two approaches. In the first approach, a new- entrant enterprise adjusts its size by learning market and continues to its activity. In the second approach, the enterprise does not adjust its size and exits the market. In this regard, the study of size distribution of new enterprises in Iran’s textile industry is the main purpose of this research. We collect statistical data for new textile businesses during 1997-2005 from Statistical Center of Iran. We use nonparametric method and indicators of employment, output value and value-added for evaluation of the size distribution. The results indicate that the employment size distribution follows an active learning model and does not adapt itself with market conditions. Regarding output value and value-added, the textile businesses follow a passive learning model and converge to the Lognormal distribution. The inability of firms in convergence by employment and their ability in convergence by output and value added criteria are some signs of a rigid labor market in Iran. According to these findings, reconsidering the labor law in order to making it more flexible is essential.

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Industrial firms play important roles in creating jobs and products nationwide, thus, their survival is of vital importance. The existing studies on closure of the firms show that various factors contribute to the exit of firms from the industry which industry growth is the main factor in this context. Industry growth affects the exit of firms in different ways, for instance, industries having high growth are of high entry rate that influences significantly on the firms exit. This study examines the industry growth effect on exit of firms from industry and uses an artificial neural network (ANN) model for this purpose. The statistical population includes 10000 industrial firms at 4-digit level ISIC codes during the third national development plan over the 2000-2004. The industry growth is calculated with different indexes such as absolute growth and mean growth rates. The results show that industry growth followed at firm size can explain the most of exit incentives of the firms.