225,414 research outputs found
(WP 2010-02) The Demand for Historic Preservation
Historic preservation is commonly used to protect old buildings and neighborhoods from deterioration. In 1981, the City of Milwaukee established a historic preservation commission to develop and maintain a local register of places with historical importance to the area. The commission also reviews all applications for historic status as well as any requests for exterior alterations. As such, there are numerous rules and restrictions that are imposed on property owners once it has been declared a historic site. Thus, while historic designation can serve to internalize the externalities in neighborhoods with historic buildings, it also imposes costs on homeowners who wish to make improvements to their homes. This paper uses a hedonic model to estimate the impact of historic preservation on the sale price of a single family home in the Milwaukee area. Preliminary results show that the impact of historic preservation is positive when it is significant, with the average impact at 26.6%. However, there was significant variation between districts, with the impact significantly positive in 13 of 22 districts used in the sample. Specifically, the positive impact ranged between 11% and 65%, holding other factors constant. None of the 22 districts had a negative and significant impact. An evaluation of spillover effects reveal that just over one third of them displayed positive and significant spillover effects, whereas 21% had negative and significant spillover effects. The remainder were insignificant. An important question is what factors influence this variability in historic preservation effects. The eventual goal of this research is to extend our preliminary analysis to two stages using a recently developed method that employs spatial econometric methods to solve the unique identification problems inherent in hedonic models (Carruthers and Clark, forthcoming in Journal of Regional Science). This will permit us to determine the specific factors that influence these premiums. While the spatial estimates presented in this preliminary work do not permit a two-stage model, we did explore whether implicit prices appear to be correlated with the household income and racial makeup of the neighborhoods in which they are located. The findings show little evidence that the implicit values of historic districts are correlated, but the implicit price associated with historic district spillovers was positively correlated with both neighborhood measures
Rule-based Autoregressive Moving Average Models for Forecasting Load on Special Days: A Case Study for France
This paper presents a case study on short-term load forecasting for France,
with emphasis on special days, such as public holidays. We investigate the
generalisability to French data of a recently proposed approach, which
generates forecasts for normal and special days in a coherent and unified
framework, by incorporating subjective judgment in univariate statistical
models using a rule-based methodology. The intraday, intraweek, and intrayear
seasonality in load are accommodated using a rule-based triple seasonal
adaptation of a seasonal autoregressive moving average (SARMA) model. We find
that, for application to French load, the method requires an important
adaption. We also adapt a recently proposed SARMA model that accommodates
special day effects on an hourly basis using indicator variables. Using a rule
formulated specifically for the French load, we compare the SARMA models with a
range of different benchmark methods based on an evaluation of their point and
density forecast accuracy. As sophisticated benchmarks, we employ the
rule-based triple seasonal adaptations of Holt-Winters-Taylor (HWT) exponential
smoothing and artificial neural networks (ANNs). We use nine years of
half-hourly French load data, and consider lead times ranging from one
half-hour up to a day ahead. The rule-based SARMA approach generated the most
accurate forecasts.Comment: 11 figures, 3 table
Endogenous Amenities and the Spatial Structure of Cities
This paper examines the endogenous dynamics of the social structure of a city where the spatial repartition of amenities is endogenously modified by the spatial repartition of social groups. We start from the fact that, in most European cities, central locations are occupied by rich households; while in American cities, they are occupied by poor households. In a standard urban model without amenities, for rich households to locate downtown, their unit transport cost must be very high compared to the poor. Bruckner et al. (1999) show that, when there are historical amenities mainly located in the city center, we no longer need a high differential between transport costs: if demand for amenities by the rich is strong enough, this advantage could attract the rich households in the city centre. This explanation fits well with the fact that the most European cities have a long history, with the consequence that they accumulated many amenities in their city centre. However, the paper by Brueckner et al. is purely static and does not explicitly consider the historical dimension of the process generating amenities. Our model explicitly takes account of time: at every period, the equilibrium spatial structure of the city is determined by the transport costs and by the spatial repartition of amenities; but, between periods, the spatial repartition of amenities changes, rich households generating local amenities in the locations they occupy, and then the spatial structure of the city changes. We show that this endogenous generation of local amenities has two consequences. The first one is that the city may have several long term equilibria. We explicitly analyse two of them: an ââŹĹAmerican equilibriumâ⏠with the poor living in the centre, and a ââŹĹEuropean equibriumâ⏠with the rich living in the centre. We show that the conditions for the existence of an European equilibrium are more restrictive. The second consequence is that, when the city develops, it may move from an American equilibrium to an European one. If the city starts without amenities, poor households locate in the city centre, rich households in the periphery. However, the production of new local amenities by the rich generates a lock in effect: rich go on occupying locations where they were living previously and, as the city develops, these locations become central ones.
Simple yet effective: historical proximity variables improve the species distribution models for invasive giant hogweed (Heracleum mantegazzianum s.l.) in Poland
Species distribution models are scarcely applicable to invasive species because of their breaking of the modelsâ assumptions. So far, few mechanistic, semi-mechanistic or statistical solutions like dispersal constraints or propagule limitation have been applied. We evaluated a novel quasi-semi-mechanistic approach for regional scale models, using historical proximity variables (HPV) representing a state of the population in a given moment in the past. Our aim was to test the effects of addition of HPV sets of different minimal recentness, information capacity and the total number of variables on the quality of the species distribution model for Heracleum mantegazzianum on 116000 km2 in Poland. As environmental predictors, we used fragments of 103 1Ă1 km, world- wide, free-access rasters from WorldGrids.org. Single and ensemble models were computed using BIOMOD2 package 3.1.47 working in R environment 3.1.0. The addition of HPV improved the quality of single and ensemble models from poor to good and excellent. The quality was the highest for the variants with HPVs based on the distance from the most recent past occurrences. It was mostly affected by the algorithm type, but all HPV traits (minimal recentness, information capacity, model type or the number of the time periods) were significantly important determinants. The addition of HPVs improved the quality of current projections, raising the occurrence probability in regions where the species had occurred before. We conclude that HPV addition enables semi-realistic estimation of the rate of spread and can be applied to the short-term forecasting of invasive or declining species, which also break equal-dispersal probability assumptions
Foreign banksâ attraction to the financial centre Frankfurt : a "u"-shaped relationship
This paper traces the location of foreign banks in Germany from 1949 to 2006. As suggested by new economic geography models we find a âuâ-shaped concentration of foreign banks in Germany. Only after a competition between several cities, Frankfurt has emerged as the pre-eminent financial centre, triggered by the âhistorical eventâ of setting up the German central bank in Frankfurt. After a strong increase, Frankfurtâs share in the location of foreign banks in Germany decreases slowly but significantly since the mid 1980âs. We conclude that there will be a lesser role in Europe for secondtier financial centres in the future
Conservation of the critically endangered frog Telmatobufo bullocki in fragmented temperate forests of Chile : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Conservation Biology at Massey University, Albany, New Zealand
Amphibians are currently facing several threats and are suffering severe population
declines and extinction worldwide. Telmatobufo bullocki (Anura: Calyptocephalellidae) is
one of the rarest and most endangered amphibian species in Chile's temperate forests. It is
the fifth most evolutionarily distinct and globally endangered (EDGE) amphibian in the
world, and one of the world's top 100 priority species for conservation (Zoological Society
of London, 2011).This stream-breeding frog is micro-endemic to the coastal Nahuelbuta
mountain range in central-south Chile (37°C - 38°50' S), a hot-spot for conservation. This area
has suffered severe loss and fragmentation of native forest, which has been replaced by
extensive commercial plantations of exotic pines and eucalyptus. Despite its potential
detrimental effects, the impact of native forest loss on this species has not been studied
before. Furthermore, few historical observations exist, and the ecology and behaviour of
the species is poorly known. In addition, current status and location of extant populations
are uncertain, which makes conservation and targeted habitat protection difficult.
Through the use of different approaches and modern conservation tools this thesis aims to
make a significant contribution to the conservation of T.bullocki and its habitat. Historical
and new locations were surveyed to identify extant populations. A distribution modeling
approach (i.e. Maxent) was used to infer the speciesâ distribution within Nahuelbuta,
generate a predictive habitat suitability map, identify important environmental
associations, and assess the impact of main environmental threats (i.e. native forest loss,
climate change).Field-based research (e.g. surveys, radio-tracking) was done to extend the
ecological and behavioural knowledge of the species (e.g. movement patterns and habitat
use), and identify critical aquatic and terrestrial habitat for protection (i.e. core habitat).
Mitochondrial and specifically developed microsatellite genetic markers were used to
measure levels of intra-specific genetic variability, define genetic population structure and
connectivity, infer evolutionary history (phylogeography), estimate effective population
size and detect demographic changes (e.g. bottlenecks). Finally, a landscape genetics
approach was used to relate landscape characteristics to contemporary patterns of gene
flow, and identify important landscape features facilitating (i.e. corridors) or hindering (i.e.
barriers) genetic connectivity between populations.
Telmatobufo bullocki was found in nine basins within Nahuelbuta, including historic and
new locations. Presence of T. bullocki was positively related to the amount of native
forests in the landscape. However, some populations persist in areas dominated by exotic
plantations. Some frogs were found living under mature pine plantation adjacent to native
forest, but no frogs were found in core plantation areas.T. bullocki makes extensive use of
terrestrial habitat adjacent to breeding streams during the post-breeding season, moving
up to 500 m away from streams. A core terrestrial habitat of at least 220 m from streams is
proposed for the protection of populations. Population genetics and phylogeography
revealed significant population structure. The northernmost and disjunct population of
Chivilingo is geographically and genetically isolated from all other sampled populations and
was identified as a separate evolutionary significant unit (ESU). The population of Los
Lleulles was also identified as a separate management unit, while the remaining
populations were grouped into two clusters forming a larger and more connected metaC
population. Connectivity within groups was high, suggesting individuals are able to
disperse between neighbouring basins. Levels of genetic diversity were not homogeneous,
and were lowest at Los Lleulles and highest at CaramĂĄvida. Results suggest disjunct
populations are at highest risk and should be prioritised for restoration and habitat
protection, while management of metaCpopulations should aim at maintaining and
improving connectivity among basins. Landscape genetic results identified streams and
riparian habitat as dispersal pathways, and least-cost-path analysis was used to identify a
potential connectivity network
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