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on Discrete Choice Models |
| By: | Dolado, Juan José; Morales, Eduardo |
| Abstract: | This paper analyses the determinants of academic performance of first-year undergraduate students in Economics at Universidad Carlos III de Madrid, over the period 2001-2005. We focus on a few core subjects which differ in their degree of mathematical complexity. Type of school, specialization track at high school, and the grades obtained at the university entry-exam are among the key factors we examine. Our main finding is that those students who completed a technical track at high school tend to do much better in subjects involving mathematics than those who followed a social sciences track (tailor-made for future economics students) and that the latter do not perform significantly better than the former in subjects with less degree of formalism. Moreover, students from public schools are predominant in the lower and upper parts of the grade distribution while females tend to perform better than males. |
| Keywords: | academic performance; multinomial logit; pre-university determinants; quantile regressions |
| JEL: | I21 I29 |
| Date: | 2007–03 |
| URL: | http://d.repec.org/n?u=RePEc:cpr:ceprdp:6237&r=dcm |
| By: | Schmidt, Tobias |
| Abstract: | Theoretical considerations suggest that secrecy reduces spillovers almost completely through non-disclosure, while the disclosure requirement of patents generates some spillover and at the same time allows firms to appropriate knowledge. In this paper we empirically analyze whether protection by secrecy or protection by patents is associated with lower knowledge spillovers. Since the amount of knowledge spillovers is hard to measure directly, we look at the impact of the usage of protection methods in an industry on the innovation activities of firms using external knowledge. One goal is to assess if firms have moved to a more open innovation business model, i.e. allow more knowledge spillovers to occur despite using protection methods. Our estimations show that the usage of both, patents and secrecy, hinders the innovation activities of firms through the reduction of spillovers to firms in their own industry. We conclude that the appropriability effect of patents outweighs the disclosure effect. We also find some evidence that the open innovation business model has not been implemented widely. |
| Keywords: | Knowledge Spillovers, patents, secrecy, open innovation, ordered probit |
| Date: | 2006 |
| URL: | http://d.repec.org/n?u=RePEc:zbw:zewdip:5441&r=dcm |
| By: | Lei Zhang; David Levinson (Nexus (Networks, Economics, and Urban Systems) Research Group, Department of Civil Engineering, University of Minnesota) |
| Abstract: | A major strategy of federal ITS initiatives and state departments of transportation is to provide traveler information to motorists through various means, including variable message signs, the internet, telephone services like 511, in-vehicle guidance systems, and TV and radio reports. This is relatively uncontroversial, but its effectiveness is unknown. Drivers receive value from traveler information in several ways, including the ability to save time, but perhaps more importantly, other personal, social, safety, or psychological impacts from certainty. This information can be economically valued. The benefits of reduction in driver uncertainty when information is provided at the beginning of the trip by various means is the main variable we aim to measure in this research, in which we assess user preferences for routes as a function of the presence and accuracy of information, while controlling for other trip and route attributes, such as trip purpose, travel time, distance, number of stops, delay, esthetics, level of commercial development, and individual characteristics. Data is collected in a field experiment in which more than 100 drivers, given real-time travel time information with varying degrees of accuracy, drove four of five alternative routes between a pre-selected OD pair in the Twin Cities metro area. Ordinary regression, multinomial, and rank-ordered logit models produce estimates of the value of information with some variation. In general, results show that travelers are willing to pay up to $1 per trip for pre-trip travel time information. The value of information is higher for commute and event trips and when congestion on the usual route is heavier. The accuracy of the traveler information is also a crucial factor. In fact, there do not seem be incentives for travelers to use traveler information at all unless they perceive it to be accurate. Finally, most travelers (70%) prefer that such information should be provided for free by the public sector, while some (19%) believe that it is better for the private sector to provide such service at a charge. Over 35% of subjects are willing to pay for OD-customized pre-trip travel time information. |
| Keywords: | Value of Information, Advanced Traveler Information System (ATIS), Real-Time Traffic Operations, Travel Behavior, Spatial behavior, Wayfinding Behavior, Route Choice. |
| JEL: | R41 R48 D10 D83 D85 C93 C91 |
| Date: | 2006 |
| URL: | http://d.repec.org/n?u=RePEc:nex:wpaper:determinantsofroutechoice&r=dcm |
| By: | Michael Corbett; Feng Xie; David Levinson (Nexus (Networks, Economics, and Urban Systems) Research Group, Department of Civil Engineering, University of Minnesota) |
| Abstract: | This paper describes and explains the growth of the Minneapolis Skyway network. Accessibility is used as a major factor in understanding that growth (i.e. does the network connect to the location(s) with the highest accessibility, followed by the second highest, and so on). First, employment opportunities are used as the measure of activity and are based off of the square footage of buildings and/or ITE trip generation rates. Using information about the buildings located downtown for each year since the first skyway was built, the accessibilities of each of the connected and adjacent unconnected blocks were calculated for every time period the skyway system expanded. The purpose is to determine how often the expansion connected the block with the highest accessibility. The results show that though important, accessibility was rarely maximized, except in the early stages of development. A connect-choice logit model relating the probability of joining the network (in a given year) to accessibility and network size was employed. The results show accessibility does remain an important factor in predicting which links are connected. Physical difficulties in making connections may have played a role, as well as the potential for adverse economic impacts. |
| Keywords: | Network growth, Transport economics, Incremental connection, Skyways, Minneapolis |
| JEL: | R41 R42 R48 O33 |
| Date: | 2007 |
| URL: | http://d.repec.org/n?u=RePEc:nex:wpaper:skyways&r=dcm |
| By: | Lei Zhang; Feng xie; David Levinson (Nexus (Networks, Economics, and Urban Systems) Research Group, Department of Civil Engineering, University of Minnesota) |
| Abstract: | This paper explores drivers' subjective value of time under moving and stopped freeway travel conditions using a stated preference survey. Unlike previous studies that assume a constant value of time, this research relates perceived satisfaction of a freeway trip to its quality indicators. Sixty-nine subjects in the Twin Cities are asked in the survey to rank sixteen driving scenarios in four condition sets with different durations of ramp wait and freeway travel. Several utility functions are specified where the weight of ramp delay is a function of the length of the delay itself and subject specific variables, and the resulting choice models estimated using rank-ordered logit and binary logit techniques. Results suggest that drivers perceive ramp wait as more onerous than freeway travel. Drivers also weight each minute of ramp wait more heavily as the length of the delay gets longer. Although the subjects show some tolerance to the first several minutes of ramp delay (less than 5 minutes), they perceive long delays as much as twelve times more onerous than time in motion. The derived weighting function for ramp wait can improve the design of freeway traffic control strategies that trade-off freeway delay with ramp wait. The findings also enable a more utility-based approach for freeway operations than the current method which has the engineering efficiency objective of minimizing total system delay or maximizing throughput. Minimizing total perceived travel time is probably more appropriate than minimizing total absolute travel time which does not take into account driver acceptance. The weighting function can also be easily transformed into a value of time function for project evaluation purposes. |
| Keywords: | Value of time, value of travel time, Time perception, Driver acceptance, Freeway congestion, Ramp meter |
| JEL: | R40 R42 R48 D10 C91 |
| Date: | 2007 |
| URL: | http://d.repec.org/n?u=RePEc:nex:wpaper:svtt&r=dcm |
| By: | Valerio Gatta (Facoltà di Scienze Statistiche ed Economiche, Università di Roma "La Sapienza"); Edoardo Marcucci (Department of Economics, Università di Urbino "Carlo Bo") |
| Abstract: | Public authorities and transport operators are both involved in the provision of public transport services. There is a contrast between the social goals of the former and the private ones of the latter. Regulation plays an important role especially failing competition. Service contracts are the natural method to set bilateral After a brief description of the most important regulatory procedures, we focus our attention on the quality framework in service contracts. In recent years the inclusion of quality requirements in contracts is becoming common practice, especially when adopting price cap regulation. This paper suggests a criterion for service quality definition, measurement and integration in contracts for the production of socially valuable transport services. Using stated preferences methods and choice-based conjoint analysis to analyse customer preferences we estimate the passengers’ evaluation of different service features and calculate a service quality index. A case study demonstrates the procedure to follow for measuring service quality in local public transport. |
| Keywords: | service quality, stated preferences, service contract. |
| JEL: | R40 R41 |
| Date: | 2007–03 |
| URL: | http://d.repec.org/n?u=RePEc:urb:wpaper:07_08&r=dcm |