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This article builds a simple theoretical model for the optimal expected length of a franchise contract. The main outcome is that fixed specific investment positively impacts contract duration confirming previous theoretical conjectures. Additionally, other variables such us the price–cost margin of the franchise, the brand name or the discount factor also play a relevant role. The empirical analysis using a large sample of franchises operating in Spain confirms the main conclusions of the model. However, the connection found between investment and duration, although statistically robust, is weak from an economic point of view. This result suggests the possibility that, in general, most franchisees are not in equilibrium because of the high standardization of this contract term across franchises. In these cases, the expectation of renewal is likely to be a crucial element of adjustment.  相似文献   
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POPULATION: We have analyzed the distribution of the allele frequencies and parameters of forensic interest at nine short tandem repeat (STR) loci (CSF1PO, D3S1358, D5S818, D7S820, D13S317, FGA, TH01, TPOX, and vWA) in a sample population of 165 unrelated individuals from César and Guajira, Caribbean populations of Colombia.  相似文献   
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Allele frequency data for the 15 STR systems and Amelogenine were determined in a population sample of healthy Amerinidian Kichwas and Blacks individuals. All loci met Hardy–Weinberg expectations and the high discrimination power of combined system showed the forensic efficiency of these genetic markers.  相似文献   
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The purpose of this paper is to determine how NAFTA influenced the Mexican tourism sector and its effects on the environment. The linkage between the tourism sector and NAFTA is done through the analysis of foreign direct investment and cross-border trade in services. The quantitative section of the paper focuses on analyzing commercial presence in the form of hotels and restaurants, as well as the use of services abroad. The paper concludes that NAFTA represented greater certainty to investors but was not the main driver behind the investments in tourism services. The analysis of visitors from US and Canada in Mexico recognizes that NAFTA did not have significant impact on the tourism flow. NAAEC, on the other hand, serves in this research as a qualitative connection between tourism sector and the environment for attending to citizen submissions on failures in environmental law enforcement in Mexico regarding tourism projects. It is included with an economic-environmental balance in Cancun—which shows that the greatest environmental impact is of global importance: CO2 released into the air by air transportation, followed by the local impact of water consumption, waste generation, and electricity usage, in that order.  相似文献   
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