Showing papers on "Occupancy published in 2001"

Inferring process from pattern: can territory occupancy provide information about life history parameters?

Abstract: A significant problem in wildlife management is identifying "good" habitat for species within the short time frames demanded by policy makers. Statistical models of the response of species presence/absence to predictor variables are one solution, widely known as habitat modeling. We use a "virtual ecologist" to test logistic regression as a means of developing habitat models within a spatially explicit, individual-based simulation that allows habitat quality to influence either fecundity or survival with a continuous scale. The basic question is how good are logistic regression models of habitat quality at identifying habitat where birth rates are high and death rates low (i.e., "source" habitat)? We find that, even when all the important variables are perfectly measured, and there is no error in surveying the species of interest, demographic stochasticity and the limiting effect of localized dispersal generally prevent an explanation of much more than half of the variation in territory occupancy as a function of habitat quality. This is true regardless of whether fecundity or survival is influenced by habitat quality. In addition, habitat models only detect a significant effect of habitat on territory occupancy when habitat quality is spatially autocorrelated. We find that habitat models based on logistic regression really measure the ability of the species to reach and colonize areas, not birth or death rates.

High Occupancy Vehicle Lanes: Not Always More Effective Than General Purpose Lanes

Abstract: The success of a high occupancy vehicle lane in motivating people to shift to carpools and buses depends on maintaining a travel time differential between it and the adjacent general purpose lanes. This differential, in turn, depends on the level of continuing delay on the general purpose lanes. Therefore, it is clear that a high occupancy vehicle lane that will motivate people to shift to high occupancy vehicles will not eliminate congestion. Consequently, it is not clear that constructing a high occupancy vehicle lane will necessarily reduce delay more than construction of a general purpose lane. The objective of this research is to determine the circumstances in which this would be the case. The hypothesis is that such circumstances would be quite limited, and this proves to be the case. The intended benefits of high occupancy lanes are defined as reduced person-delay and reduced emissions. A model is developed to calculate these benefits for four alternatives add a high occupancy vehicle lane, add a general purpose lane, convert an existing lane to a high occupancy vehicle lane, and do nothing. The model takes into account the initial conditions, the dynamic nature of the travel time differential between the high occupancy vehicle lane and other lanes, and the uncertainty regarding the extent to which people will shift modes. It combines queueing theory and mode choice theory and provides a robust method for comparing alternatives using a small amount of easily observed data. Application of the model in typical situations shows that with initial delays on the order of 15 min or more, adding a high occupancy vehicle lane would provide substantial reductions in delay and some reduction in emissions. However, in a wide range of such situations, adding a general purpose lane would be even more effective. Only if the initial delay is long and the initial proportion of high occupancy vehicles falls in a rather narrow range, would an added high occupancy vehicle lane be more effective. The proportion of high occupancy vehicles must be such that it allows good utilization of the high occupancy vehicle lane while maintaining a sufficient travel time differential to motivate a shift to buses or carpools. Adding a high occupancy vehicle lane to a three lane freeway will be more effective than adding a general purpose lane only if the initial maximum delay is on the order of 35 min or more and the proportion of high occupancy vehicles is on the order of 20%. Federal policies encourage construction of high occupancy vehicle lanes and restrict funding for general purpose lanes in areas that have not attained air quality standards. The findings of this research suggest a need to reconsider these policies.

On the Prediction of Lighting Energy Savings Achieved by Occupancy Sensors

Abstract: Advanced lighting controls are used to reduce lighting energy consumption. One such control is the use of occupancy sensors. Energy savings achievable by occupancy sensors depend on the occupancy pattern, which is related to building and occupant characteristics. The occupancy pattern has some degree of randomness for many building types. This article describes a method for the prediction of occupancy and lighting energy consumption based on user defined probabilities. Real lighting energy consumption from a recent retrofit program was used to demonstrate the model calculation. Comparison of the energy saving potential from different delay time settings was also made.

Accounting for the Occupancy Variable in Inverse Building Energy Baselining Models

Abstract: The occupancy factor is often underestimated in inverse modeling of building energy use, or accounted for by grouping the daily data in occupied and unoccupied groups which are modeled separately. For instance, in institutional buildings it is common to identify "weekdays/weekends", "semester breaks", and "holidays" daytypes. In order to develop one model that accounts for all periods, i.e., occupied and unoccupied, at an hourly time scale, a dummy variable (regressor) can be used. The dummy variable is often used in a simplified way; for instance, having a value of 0 between 8:00 AM and 5:00 PM, and 1 between 5:00 PM and 8:00 AM, for an office building. In this paper, the effect of using different alternatives in accounting for the occupancy variable in inverse modeling of building energy use is investigated, and the resulting uncertainty in the predictions, using the SMLP inverse method are presented.

A simple landscape-scale test of a spatially explicit population model: patch occupancy in fragmented south-eastern Australian forests

Abstract: The results of a landscape-scale test of ALEX, a widely used metapopulation model for Population Viability Analysis (PVA), are described. ALEX was used to predict patch occupancy by the laughing kookaburra and the sacred kingfisher in patches of eucalypt forest in south-eastern Australia. These predictions were compared to field surveys to determine the accuracy of the model. Predictions also were compared to a "naive" null model assuming no fragmentation effects. The naive null model significantly over-predicted the number of eucalypt patches occupied by the sacred kingfisher, but the observed patch occupancy was not significantly different from that predicted using ALEX. ALEX produced a better fit to the field data than the naive null model for the number of patches occupied by the laughing kookaburra. Nevertheless, ALEX still significantly over-predicted the number of occupied patches, particularly remnants dominated by certain forest types – ribbon gum and narrow-leaved peppermint. The predictions remained significantly different from observations, even when the habitat quality of these patches was reduced to zero. Changing the rate of dispersal improved overall predicted patch occupancy, but occupancy rates for the different forest types remained significantly different from the field observations. The lack of congruence between field data and model predictions could have arisen because the laughing kookaburra may move between an array of patches to access spatially separated food and nesting resources in response to fragmentation. Alternatively, inter-specific competition may be heightened in a fragmented habitat. These types of responses to fragmentation are not incorporated as part of traditionally applied metapopulation models. Assessments of predictions from PVA models are rare but important because they can reveal the types of species for which forecasts are accurate and those for which they are not. This can assist the collection of additional empirical data to identify important factors affecting population dynamics.

Multivariate models of hotel occupancy performance and their implications for hotel marketing

Abstract: Multivariate models are developed to explain the differential occupancy performance of a sample of 279 English hotels Following a procedure established in an earlier paper, hotels are first differentiated on the basis of their overall occupancy performance, seasonality, long-term trend and length of season Regression models are specified and calibrated to relate each of these dimensions of occupancy performance to the location and other characteristics of the hotels The four models produce the expected positions of hotels in ‘occupancy performance space’, against which their observed positions can be compared The application of the models in hotel marketing is discussed and demonstrated Copyright © 2001 John Wiley & Sons, Ltd

Hotel values: In the aftermath of September 11, 2001

Abstract: This model of hotel values once again demonstrates the importance of maintaining solid fundamentals, such as occupancy percentage and average daily rate.

An investigation of the factors affecting guest selection of hotel/motel accommodation within New Zealand: development of a management decision model

Abstract: This research investigates the factors that influence the selection of hotel/motel accommodation in New Zealand. The tourism and hospitality industries are an important part of the New Zealand economy, with tourism producing more overseas income than any other individual industry. It is vitally important for hotel and motel owners and management to understand the factors that affect occupancy in order that they may implement decisions to take best advantage of the assets and obtain the highest return on the investment. A holistic approach or one that looks at the many factors influencing hotel occupancy has been adopted as this encourages an interdisciplinary method to the study of hotel occupancy, and broadens the investigation. This gives the research a particular focus on the problem of occupancy because the analysis includes an extensive spectrum of factors. The specific objective is to investigate the factors that influence occupancy and to produce the findings in the form of a management decision model. The data for this research was gathered from three sources: first a small group of researchers and industry stakeholders participated in-depth interviews, which comprised open questions asked to determine from their perspective the factors that have the greatest affect on occupancy. The main findings from these interviews were used to develop a survey conducted among hotel decision-makers; management was specifically chosen for this, as it was believed that there would be a broader knowledge and experience base. The final set of data was collected from a survey of potential guests. In developing the management decision model, a number of tools were employed including neural networks and linear structural equation modelling. These analyses gave a rich result to the findings and this was applied to the development of stochastic¹ management decision models (Goel & Richter-Dyn, 1974; Bekker & Saayman, 1999), using the main findings from the interviews with researchers and industry stakeholders as a reference point. The contribution of this research included evidence of: 1). The significant “Gap” between the factors influencing occupancy relating to researchers and industry stakeholders and hotel decision-makers on the one hand and potential guests on the other; 2). The structure and factors involved within a hotel occupancy decision model; 3). The demographic influences on the factors within the management decision model. ¹The way in which the variables within the model relate and impact on each other.

Treaty land entitlement in Saskatchewan : conflicts in land use and occupancy in the Witchekan Lake area

Abstract: This thesis examines the creation of the Witchekan Lake Reserve in Saskatchewan, the resulting treaty land entitlement (TLE) for Witchekan Lake First Nation, and the 1992 Framework Agreement for Saskatchewan Treaty Land Entitlenzent (TLEFA). The history of the Witchekan Lake Reserve between 19 13 and 19 19 is reconstructed and reveals a unique situation within TLE. The creation of a Reserve some thirty-seven years prior to adherence to Treaty Six presents a challenge to the interpretation of TL,E. It also points to the importance of the historical context of Reserve creation within TLE. A study of land use and occupancy of Witchekan Lake First Nation and the area occupied by Settlers was facilitated by the use of Department of Indian Affairs files, map biographies, oral interviews, transcripts of earlier interviews with deceased elders, records and correspondence from Saskatchewan Environment and Resource Mangement (SERM) and the Department of the Interior Homestead Files. The analysis employs a non-traditional definition of the ethnicity of Settlers. That defmition is based on their birthplace, their land use and their life experiences before arriving at Witchekan Lake. Employing theoretical concepts of colonization and underlying ideologies of racial inferiority, the work proposes that the existence of two opposing types of land use and occupancy and their respective value systems led to a TLE for Witchekan Lake First Nation. It is argued here that these ideologies were present in the homestead period and have persisted into the present due to the late timing of settlement and the pluralistic composition of Settlers. A review of the events around the acquisition of the Bapaume Community Pasture by Witchekan Lake First Nation demonstrates the continuance of conflict with Settlers. This conflict first arose in the homestead era. A critique of the TLEFA, specific to the case of Witchekan Lake First Nation, proposes that lack of attention to their unique circumstances has left the community with unresolved claims. The community hoped that these unresolved claims would be settled in the TLEFA.