| 1. |
- Zhao, Xiaoyun, et al.
(författare)
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An Evaluation of the Reliability of GPS-Based Transportation Data
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- GPS-based data are becoming a cornerstone for real-time transportation applications. Tracking data of vehicles from GPS receivers are however susceptible to measurement errors. The assessment of the reliability of data from GPS receiver is a neglected issue, especially in a real road network setting and in the phase after data transfer but before information identification. An evaluation method is outlined and carried out by conducting a randomized experiment. We assess the reliability of GPS-based transportation data on geographical position, speed, and elevation from three varied receivers GlobalSat BT-338X, Magellan SporTrak Pro and smart phone for three transportation modes: bicycle, car, and bus. The positional error ranging from 0158 meters, and 74% to 100% with an error within 5 meters depending on the transportation mode and route, there is also a non-negligible risk for aberrant positioning. Speed is slightly underestimated or overestimated with errors around 5km/h except for SporTrak Pro which had an error
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| 2. |
- Carling, Kenneth, et al.
(författare)
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Short Communication: A compelling argument for the gravity p-median model
- 2012
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The p-median model is used to locate P facilities to serve a geographically distributed population. Conventionally, it is assumed that the population always travels to the nearest facility. Drezner and Drezner (2006, 2007) provide three arguments on why this assumption might be incorrect, and they introduce the extended the gravity p-median model to relax the assumption. We favour the gravity p-median model, but we note that in an applied setting, Drezner and Drezner’s arguments are incomplete. In this communication, we point at the existence of a fourth compelling argument for the gravity p-median model.
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| 3. |
- Han, Mengjie, et al.
(författare)
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How do neighbouring populations affect local population change over time?
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This study covers a period when society changed from a pre-industrial agricultural society to a post-industrial service-producing society. Parallel with this social transformation, major population changes took place. In this study, we analyse how local population changes are affected by neighbouring populations. To do so we use the last 200 years of local population change that redistributed population in Sweden. We use literature to identify several different processes and spatial dependencies in the redistribution between a parish and its surrounding parishes. The analysis is based on a unique unchanged historical parish division, and we use an index of local spatial correlation to describe different kinds of spatial dependencies that have influenced the redistribution of the population. To control inherent time dependencies, we introduce a non-separable spatial temporal correlation model into the analysis of population redistribution. Hereby, several different spatial dependencies can be observed simultaneously over time. The main conclusions are that while local population changes have been highly dependent on the neighbouring populations in the 19th century, this spatial dependence have become insignificant already when two parishes is separated by 5 kilometres in the late 20th century. Another conclusion is that the time dependency in the population change is higher when the population redistribution is weak, as it currently is and as it was during the 19th century until the start of industrial revolution.
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| 4. |
- Han, Mengjie, et al.
(författare)
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To what extent do neighbouring populations affect local population growth over time?
- 2016
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Ingår i: Population, Space and Place. - : John Wiley & Sons. - 1544-8444 .- 1544-8452. ; 22:1, s. 68-83
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Tidskriftsartikel (refereegranskat)abstract
- This study covers a period when society changed from a pre-industrial agricultural society to a post-industrial service-producing society. Parallel with this social transformation, major population changes took place. In this study, we analyse to what extent local population change is affected by neighbouring populations. To do this, we focused on the last 190 years of local population change that redistributed population in Sweden. We used literature to identify several different processes in the population redistribution. The different processes implied different spatial dependencies between local population change and the surrounding populations. The analysis is based on an unchanged historical parish division, and we used an index of local spatial correlation to describe different types of spatial dependencies that influenced the redistribution of the population. To control inherent time dependencies, we introduced a non-separable spatial-temporal correlation model into the analysis of population redistribution. Hereby, several different spatial dependencies could be simultaneously observed over time. The main conclusions are that while local population changes have been highly dependent on neighbouring populations in the 19th century, this spatial dependence became insignificant already when two parishes are separated by 5 km in the late 20th century. It is argued that the only process that significantly redistributed the population at the end of the 20th century is the immigration to Sweden.
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| 5. |
- Håkansson, Johan, et al.
(författare)
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Extended local labor markets due to high speed trains : Visualization of estimations in the Swedish national travel demand forecasting tool, SAMPERS
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Wider economic benefits resulting from extended geographical mobility is one argument for investments in high-speed rail. More specifically, the argument for high-speed trains in Sweden has been that they can help to further spatially extend labor market regions which in turn has a positive effect on growth and development. In this paper the aim is to cartographically visualize the potential size of the labor markets in areas that could be affected by possible future high-speed trains. The visualization is based on the forecasts of labor mobility with public transport made by the Swedish national mobility transport forecasting tool, SAMPERS, for two alternative high-speed rail scenarios. The analysis, not surprisingly, suggests that the largest impact of high-speed trains results in the area where the future high speed rail tracks are planned to be built. This expected effect on local labor market regions of high-speed trains could mean that possible regional economic development effects also are to be expected in this area. However, the results, in general, from the SAMPERS forecasts indicaterelatively small increases in local labor market potentials.
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| 6. |
- Håkansson, Johan, et al.
(författare)
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Firm migration in the Swedish wholesale trade sector
- 2013
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Ingår i: International Review of Retail Distribution & Consumer Research. - : Taylor & Francis. - 0959-3969 .- 1466-4402. ; 23:1
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Tidskriftsartikel (refereegranskat)abstract
- This paper analyzes the determinants of firm migration in the Swedish wholesale trade sector using a unique dataset covering over 10,000 Swedish wholesale trade firms during the years 2000 to 2004. The results indicate that there are negative correlations between profits, firm age, and firm size and the probability of firm migration. There is a positive correlation between firm growth in the previous year and firm migration, indicating that growth opportunities that cannot be realized at the present location are an important motivation for migration.
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| 7. |
- Håkansson, Johan, et al.
(författare)
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How does employment density influence individuals’ wages? : A micro data approach.
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- We estimate the effect of employment density on wages in Sweden in a large geocoded data set on individuals and workplaces. Employment density is measured in four circular zones around each individual’s place of living. The data contains a rich set of control variables that we use in an instrumental variables framework. Results show a relatively strong but rather local positive effect of employment density on wages. Beyond 5 kilometers the effect becomes negative. This might indicate that the effect of agglomeration economies falls faster with distance than the effects of congestion.
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| 8. |
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| 9. |
- Håkansson, Johan, et al.
(författare)
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Predicting entry of Swedish wholesale firms into local markets
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Applying microeconomic theory, we develop a forecasting model for firm entry into local markets and test this model using data from the Swedish wholesale industry. The empirical analysis is based on directly estimating the profit function of wholesale firms. As in previous entry studies, profits are assumed to depend on firm- and location-specific factors,and the profit equation is estimated using panel data econometric techniques. Using the residuals from the profit equation estimations, we identify local markets in Sweden where firm profits are abnormally high given the level of all independent variables included in the profit function. From microeconomic theory, we then know that these local markets should have higher net entry than other markets, all else being equal, and we investigate this in a second step,also using a panel data econometric model. The results of estimating the net-entry equation indicate that four of five estimated models have more net entry in high-return municipalities, but the estimated parameter is only statistically significant at conventional levels in one of our estimated models.
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| 10. |
- Håkansson, Johan, et al.
(författare)
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Predicting entry of Swedish wholesale firms into local markets
- 2014
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Ingår i: International Review of Retail Distribution & Consumer Research. - : Taylor & Francis. - 0959-3969 .- 1466-4402.
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Tidskriftsartikel (refereegranskat)abstract
- Applying microeconomic theory, we develop a forecasting model for firm entry into local markets and test this model using data from the Swedish wholesale industry. The empirical analysis is based on directly estimating the profit function of wholesale firms. Profits are assumed to depend on firm- and location-specific factors, and the profit equation is estimated using panel data econometric techniques. Using the residuals from the profit equation estimations, we identify local markets in Sweden where firm profits are abnormally high given the level of all independent variables included in the profit function. From microeconomic theory, we then know that these local markets should have higher net entry than other markets, all else being equal, and we investigate this in a second step, also using a panel data econometric model. The results of estimating the net-entry equation indicate that 19 out of 30 estimated models have more net entry in high-return municipalities, but the estimated parameter is only statistically significant at conventional levels in one of our estimated models, and then with an unexpected negative sign.
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