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Article
Publication date: 23 November 2012

Didem Dizdaroglu, Tan Yigitcanlar and Les Dawes

As a consequence of rapid urbanisation and globalisation, cities have become the engines of population and economic growth. Hence, natural resources in and around the…

Abstract

Purpose

As a consequence of rapid urbanisation and globalisation, cities have become the engines of population and economic growth. Hence, natural resources in and around the cities have been exposed to externalities of urban development processes. This paper introduces a new sustainability assessment approach that is tested in a pilot study. The paper aims to assist policy‐makers and planners investigating the impacts of development on environmental systems, and produce effective policies for sustainable urban development.

Design/methodology/approach

The paper introduces an indicator‐based indexing model entitled “Indexing Model for the Assessment of Sustainable Urban Ecosystems” (ASSURE). The ASSURE indexing model produces a set of micro‐level environmental sustainability indices that is aimed to be used in the evaluation and monitoring of the interaction between human activities and urban ecosystems. The model is an innovative approach designed to assess the resilience of ecosystems towards impacts of current development plans and the results serve as a guide for policy‐makers to take actions towards achieving sustainability.

Findings

The indexing model has been tested in a pilot case study within the Gold Coast City, Queensland, Australia. This paper presents the methodology of the model and outlines the preliminary findings of the pilot study. The paper concludes with a discussion on the findings and recommendations put forward for future development and implementation of the model.

Originality/value

Presently, there is a few sustainability indices developed to measure the sustainability at local, regional, national and international levels. However, due to challenges in data collection difficulties and availability of local data, there is no effective assessment model at the micro‐level that the assessment of urban ecosystem sustainability accurately. The model introduced in this paper fills this gap by focusing on parcel‐scale and benchmarking the environmental performance in micro‐level.

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Article
Publication date: 9 March 2021

Dang Luo, Yan Hu and Decai Sun

The purpose of this paper is to establish a grey cloud incidence clustering model to assess the drought disaster degree under 15 indexes in 18 cities of Henan province.

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Abstract

Purpose

The purpose of this paper is to establish a grey cloud incidence clustering model to assess the drought disaster degree under 15 indexes in 18 cities of Henan province.

Design/methodology/approach

The grey incidence degree between each index and ideal index is used to determine the index weight and combined with the subjective weight, the comprehensive weight is given; the traditional possibility function is transformed into grey cloud possibility function by using the principle of maximum deviation and maximum entropy, which fully reflects the coexistence of multiple decision-making conclusions and constructs the grey cloud incidence clustering model.

Findings

The drought disaster degree of Henan province is divided into four grades under the selected 15 indexes. The drought grades show obvious regional differences. The risk levels of the east and southwest are higher, and the risk levels of the north and southeast are lower. This result is consistent with the study of drought disaster grades in Henan province, which shows the practicability and usefulness of the model.

Practical implications

It provides an effective method for the assessment of drought disaster grade and the basis for formulating disaster prevention and mitigation plan.

Originality/value

By studying the method of multiattribute and multistage decision-making with interval grey number information. The objective weight model of index value is designed, and the subjective weight is given by experts. On the basis of the two, the comprehensive weight of subjective and objective combination is proposed, which effectively weakens the randomness of subjective weight and reasonably reflects the practicality of index decision-making. The time weight reflects the dynamic of the index. The traditional possibility function is transformed into the grey cloud possibility function, which effectively takes advantage of the grey cloud model in dealing with the coexistence of fuzzy information, grey information and random information. Thus, the conflict between the decision-making results and the objective reality is effectively solved. The interval grey number can make full use of the effective information and improve the accuracy of the actual information.

Details

Grey Systems: Theory and Application, vol. 12 no. 1
Type: Research Article
ISSN: 2043-9377

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Article
Publication date: 29 March 2013

Anthony Owusu‐Ansah

The purpose of this paper is to examine if temporal aggregation matters in the construction of house price indices and to test the accuracy of alternative index

Abstract

Purpose

The purpose of this paper is to examine if temporal aggregation matters in the construction of house price indices and to test the accuracy of alternative index construction methods.

Design/methodology/approach

Five index construction models based on the hedonic, repeat‐sales and hybrid methods are examined. The accuracy of the alternative index construction methods are examined using the mean squared error and out‐of‐sample technique. Monthly, quarterly, semi‐yearly and yearly indices are constructed for each of the methods and six null hypotheses are tested to examine the temporal aggregation effect.

Findings

Overall, the hedonic is the best method to use. While running separate regressions to estimate the index is best at the broader level of time aggregation like the annual, pooling data together and including time dummies to estimate the index is the best at the lower level of time aggregation. The repeat‐sales method is the least preferred method. The results also show that it is important to limit time to the lowest level of temporal aggregation when construction property price indices.

Practical implications

This paper provides alternative method, the mean squared error method based on an out‐of‐sample technique to evaluate the accuracy of alternative index construction methods.

Originality/value

The introduction of financial products like the property derivatives and home equity insurances to the financial market calls for accurate and robust property price indices. However, the index method and level of temporal aggregation to use still remain unresolved in the index construction literature. This paper contributes to fill these gaps.

Details

Property Management, vol. 31 no. 2
Type: Research Article
ISSN: 0263-7472

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Article
Publication date: 30 September 2014

Anthony Owusu-Ansah and Raymond Talinbe Abdulai

The purpose of this paper is to test the accuracy of the explicit time variable (ETV) and the strictly cross-sectional (SCS) hedonic models when constructing house price…

Abstract

Purpose

The purpose of this paper is to test the accuracy of the explicit time variable (ETV) and the strictly cross-sectional (SCS) hedonic models when constructing house price indices in developing markets using Ghana as a case study.

Design/methodology/approach

The quantitative research methodology is adopted where the accuracy of the two hedonic models used in the construction of house price indices is examined using the mean squared error (MSE) and out-of-sample technique. Yearly indices are constructed for each of the models using 60 per cent of the sample data and 40 per cent is used to forecast house prices for each observations based on which the MSEs are calculated.

Findings

The two models produce similar house price trend but the SCS model is more volatile. The ETV model produces the lower MSE, suggesting that it is better to pool data together and includes time dummies (ETV) to estimate indices rather than running separate regressions (SCS) to estimate the index. Using the Morgan–Granger–Newbold test, it is found that indeed the difference between the forecast errors of the two models are statistically significant on a 1 per cent level confirming the accuracy of the ETV model over the SCS model.

Practical implications

This paper has produced convincing results recommending the use of the ETV hedonic model to construct house price indices which is of use to practitioners and academics.

Originality/value

The introduction of financial products like the property derivatives and home equity insurances to the financial market calls for accurate and robust property price indices and the hedonic method is mostly used to construct these indices. While there have been a lot of test conducted as to which variant of the hedonic method to use in developed markets, little is known about the developing markets. This paper contributes to fill these gaps.

Details

International Journal of Housing Markets and Analysis, vol. 7 no. 4
Type: Research Article
ISSN: 1753-8270

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Article
Publication date: 14 September 2020

Qiang Bu and Jeffrey Forrest

The purpose of this study is to investigate whether the direct and indirect sentiment measures are similar in explaining mutual fund performance.

Abstract

Purpose

The purpose of this study is to investigate whether the direct and indirect sentiment measures are similar in explaining mutual fund performance.

Design/methodology/approach

The authors examine the role of direct and indirect sentiment measures on fund performance in two scenarios. One is when a sentiment measure is added to market models, and the other is when it used independently. Also, the authors propose a system science theory to explain the findings.

Findings

The authors find that both direct and indirect sentiment measures are integral to the benchmark models to explain fund performance. However, while the explanatory power of the direct sentiment index is robust when used independently or collectively, the indirect sentiment measures can explain fund performance only when used along with other market factors.

Originality/value

Given the number of sentiment measures, it is critical to determine whether these measures contain the same information of sentiment. This paper represents the first study on this topic.

Details

International Journal of Managerial Finance, vol. 17 no. 3
Type: Research Article
ISSN: 1743-9132

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Article
Publication date: 1 February 1977

S.E. ROBERTSON

This paper is concerned with recent work in the theory of information retrieval. More particularly, it is concerned with theories which tackle the problem of retrieval…

Abstract

This paper is concerned with recent work in the theory of information retrieval. More particularly, it is concerned with theories which tackle the problem of retrieval performance, in a sense which will be explained. The aim is not an exhaustive survey of such work; rather it is an analysis and synthesis of those contributions which I feel to be important or find interesting.

Details

Journal of Documentation, vol. 33 no. 2
Type: Research Article
ISSN: 0022-0418

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Article
Publication date: 1 July 2014

N. Banagaaya, W.H.A. Schilders, G. Alì and C. Tischendorf

Model order reduction (MOR) has been widely used in the electric networks but little has been done to reduce higher index differential algebraic equations (DAEs). The…

Abstract

Purpose

Model order reduction (MOR) has been widely used in the electric networks but little has been done to reduce higher index differential algebraic equations (DAEs). The paper aims to discuss these issues.

Design/methodology/approach

Most methods first do an index reduction before reducing a higher DAE but this can lead to a loss of physical properties of the system.

Findings

The paper presents a MOR method for DAEs called the index-aware MOR (IMOR) which can reduce a DAE while preserving its physical properties such as the index. The feasibility of this method is tested on real-life electric networks.

Originality/value

MOR has been widely used to reduce large systems from electric networks but little has been done to reduce higher index DAEs. Most methods first do an index reduction before reducing a large system of DAEs but this can lead to a loss of physical properties of the system. The paper presents a MOR method for DAEs called the IMOR which can reduce a DAE while preserving its physical properties such as the index. The feasibility of this method is tested on real-life electric networks.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 33 no. 4
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 2 May 2017

Wan-Huan Zhou, Ankit Garg and Akhil Garg

Water balance is measured by transpiration, which has a significant impact on the performance of geotechnical infrastructure (vegetated slopes), ecological infrastructure…

Abstract

Purpose

Water balance is measured by transpiration, which has a significant impact on the performance of geotechnical infrastructure (vegetated slopes), ecological infrastructure (wetlands), urban infrastructure (green roof, biofiltration units) and agricultural infrastructure. Past studies have formulated models using analytical modeling to evaluate the transpiration index based on energy balance and suction. In circumstance of impartial and uncertain information about the root and shoot properties and its effect on the transpiration index, the present work aims to introduce the new optimization algorithm of genetic programming (GP) to quantify and optimize the transpiration index of plant.

Design/methodology/approach

The GP framework, having objective function of structural risk minimization, is used for formulating the transpiration index model. The statistical metrics with 2D and 3D analyses of the models are conducted to determine its accuracy and understand the transpiration process.

Findings

The model analysis reveals that the proposed model extrapolates the transpiration index values accurately based on five inputs. 2D and 3D relationships between the transpiration index and the five inputs suggest that the total root area has the highest impact on the transpiration index followed by shoot length and root biomass. There is not much impact of the shoot mass and stem basal diameter on the transpiration index. It was also found that the transpiration index increases with an increase in total root area and root biomass.

Originality/value

This work is a first-of-its-kind study involving the extensive computation analysis for quantifying and optimizing the transpiration index of the soil for the complex civil systems.

Details

Engineering Computations, vol. 34 no. 3
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 25 February 2014

Patrick Lecomte

The paper aims to conduct an empirical study of three models of property derivatives: index-based derivatives, factor hedges, and combinative hedges based on index and…

Abstract

Purpose

The paper aims to conduct an empirical study of three models of property derivatives: index-based derivatives, factor hedges, and combinative hedges based on index and factors. The objective is to test whether the latter two models introduced by Lecomte dominate the index-based model used for existing property derivatives such as EUREX futures contracts.

Design/methodology/approach

Based on investment property database (IPD) historical database covering 224 individual office properties from 1981 to 2007, the study assesses ex ante hedging effectiveness of the three models. Nine simulations are run under different hypotheses involving individual buildings and portfolios. The 17 factors included in the study cover both macro-factors (e.g. macroeconomic indicators) and micro-factors linked to the properties (e.g. age).

Findings

Atomization and periodic rebalancing of property derivatives' underlying make it possible to substantially increase hedging effectiveness for a large majority of buildings in the sample. However, combinative hedges are overall superior to factor hedges owing to the overriding role played by IPD indices in capturing risk.

Research limitations/implications

Due to confidentiality requirements inherent to the use of property level data, the study downplays the role of micro-factors on real estate risk at the property level.

Practical implications

The paper introduces a typology of optimal hedges aimed at individual property owners and portfolio holders in the City office property market.

Originality/value

This is the first time a comprehensive analysis of different models of property derivatives is conducted. The value of the paper stems from the use of property level data.

Details

Journal of Property Investment & Finance, vol. 32 no. 2
Type: Research Article
ISSN: 1463-578X

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Article
Publication date: 26 June 2009

Sol Kim, In Joon Kim and Seung Oh Nam

The purpose of this paper is to examine the price discovery role of the Korea Composite Stock Price Index 200 (KOSPI 200) stock index options market in contrast to other…

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Abstract

Purpose

The purpose of this paper is to examine the price discovery role of the Korea Composite Stock Price Index 200 (KOSPI 200) stock index options market in contrast to other developed options markets.

Design/methodology/approach

The price discovery roles of the stock and options markets using the error‐correction model derived from the co‐integration relationship are examined. Various analyses are conducted. First, Heston's stochastic volatility option pricing model is employed to confirm its usefulness, and compare the results with the Black and Scholes (BS) model. Second, whether the out of the money (OTM) options purchased by individual investors have a stronger price discovery role than options with other moneyness is examined. Finally, whether options have a stronger price discovery role in bullish or bearish markets than in normal markets is tested.

Findings

It is found that stock index prices lead implied index prices estimated from option prices using both BS and Heston models. In regards to the OTM options, the lead‐effect of real stock index to implied index prices holds. Also it is shown that there is a weak rise in the lead effect of the options to the stock index, but the lead effect of stock index market rules over that of the options market.

Originality/value

The paper examines the price discovery role of the KOSPI 200 stock index options market in contrast to other developed options markets and the results indicate that the consensus on the Korean financial markets may be incorrect.

Details

International Journal of Managerial Finance, vol. 5 no. 3
Type: Research Article
ISSN: 1743-9132

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