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Book part
Publication date: 29 May 2009

Joseph G. Hirschberg, Jeanette N. Lye and Daniel J. Slottje

The estimation of regression models subject to linear restrictions is a widely applied technique; however, aside from simple examples, the equivalence between the linear…

Abstract

The estimation of regression models subject to linear restrictions is a widely applied technique; however, aside from simple examples, the equivalence between the linear restricted case to the reparameterization and the substitution case is rarely employed. We believe this is due to the lack of a general transformation method for changing from the definition of restrictions in terms of the unrestricted parameters to the equivalent reparameterized model and conversely from the reparameterized model to the equivalent linear restrictions for the unrestricted model. In many cases, the reparameterization method is computationally more efficient especially when estimation involves an iterative method. But the linear restriction case allows a simple method for adding and removal of restrictions.

In this chapter, we derive a general relationship that allows the conversion between the two forms of the restricted models. Examples emphasizing systems of demand equations, polynomial lagged equations, and splines are given in which the transformation from one form to the other are demonstrated as well as the combination of both forms of restrictions. In addition, we demonstrate how an alternative Wald test of the restrictions can be constructed using an augmented version of the reparameterized model.

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Quantifying Consumer Preferences
Type: Book
ISBN: 978-1-84855-313-2

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Article
Publication date: 22 May 2020

Mariusz Doszyń

The purpose of this paper is to present an algorithm of real estate mass appraisal in which the impact of attributes (real estate features) is estimated by inequality restricted…

Abstract

Purpose

The purpose of this paper is to present an algorithm of real estate mass appraisal in which the impact of attributes (real estate features) is estimated by inequality restricted least squares (IRLS) model.

Design/methodology/approach

This paper presents the algorithm of real estate mass appraisal, which was also presented in the form of an econometric model. Vital problem related to econometric models of mass appraisal is multicollinearity. In this paper, a priori knowledge about parameters is used by imposing restrictions in the form of inequalities. IRLS model is therefore used to limit negative consequences of multicollinearity. In ordinary least squares (OLS) models, estimator variances might be inflated by multicollinearity, which could lead to wrong signs of estimates. In IRLS models, estimators efficiency is higher (estimator variances are lower), which could result in better appraisals.

Findings

The final effect of the analysis is a vector of the impact of real estate attributes on their value in the mass appraisal algorithm. After making expert corrections, the algorithm was used to evaluate 318 properties from the test set. Valuation errors were also discussed.

Originality/value

Restrictions in the form of inequalities were imposed on the parameters of the econometric model, ensuring the non-negativity and monotonicity of real estate attribute impact. In case of real estate, variables are usually correlated. OLS estimators are then inflated and inefficient. Imposing restrictions in form of inequalities could improve results because IRLS estimators are more efficient. In the case of results inconsistent with theoretical assumptions, the real estate mass appraisal algorithm enables having the obtained results adjusted by an expert. This can be important for low quality databases, which is often the case in underdeveloped real estate markets. Another reason for expert correction may be the low efficiency of a given real estate market.

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Journal of European Real Estate Research , vol. 13 no. 2
Type: Research Article
ISSN: 1753-9269

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Article
Publication date: 21 June 2011

Cheng‐Hsien Chen, Te‐Hui Tsai, Ding‐Wen Yang, Yuan Kang and Yeon‐Pun Chang

The purpose of this paper is to study the influences of both the number and locations of entry holes on the static and dynamic characteristics of a rigid rotor supported by two…

Abstract

Purpose

The purpose of this paper is to study the influences of both the number and locations of entry holes on the static and dynamic characteristics of a rigid rotor supported by two double‐rows, inherently compensated aerostatic bearings.

Design/methodology/approach

The air is assumed to be perfect gas undergoing the adiabatic process and passing through entry holes into the bearing clearance. Air film in the clearance is governed by Reynolds equation including the coupled effects of wedge due to rotor rotation and squeezed film due to rotor oscillation.

Findings

The method is used to analyze Reynolds equation, which is then solved by the finite difference method and numerical integration to yield static and dynamic characteristics of air film. The equation of motion of the rotor‐bearing system is obtained by using the perturbation method and the eigensolution method is used to determine the stability threshold and critical whirl ratio.

Originality/value

The paper considers the eccentricity, rotor speed, and restriction parameter in the analysis of the whirl instability of the rotor‐aerostatic bearing system for the comparisons between various designs in the number and locations of entry holes of aerostatic bearings.

Details

Industrial Lubrication and Tribology, vol. 63 no. 4
Type: Research Article
ISSN: 0036-8792

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Abstract

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Economics of Crime: Deterrence and the Rational Offender
Type: Book
ISBN: 978-0-44482-072-3

Article
Publication date: 3 May 2011

Yuan Kang, Jian‐Lin Lee, Hua‐Chih Huang, Ching‐Yuan Lin, Hsing‐Han Lee, De‐Xing Peng and Ching‐Chu Huang

The paper aims to determine whether the type selection and parameters determination of the compensation are most important for yielding the acceptable or optimized characteristics…

Abstract

Purpose

The paper aims to determine whether the type selection and parameters determination of the compensation are most important for yielding the acceptable or optimized characteristics in design of hydrostatic bearings.

Design/methodology/approach

This paper utilizes the equations of flow equilibrium to determine the film thickness or displacement of worktable with respect to the recess pressure.

Findings

The stiffness due to compensation of constant‐flow pump increases monotonically as recess pressure increases. Also, the paper considers which is larger than that due to orifice compensation and capillary compensation at the same recess pressure ratio.

Originality/value

The findings show that the usage range of recess pressure and compensation parameters can be selected to correspond to the smallest gradient in variations of worktable displacement or film thickness.

Details

Industrial Lubrication and Tribology, vol. 63 no. 3
Type: Research Article
ISSN: 0036-8792

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Abstract

Details

New Directions in Macromodelling
Type: Book
ISBN: 978-1-84950-830-8

Book part
Publication date: 14 July 2004

Anders Forslund and Ann-Sofie Kolm

A number of earlier studies have examined whether extensive labour market programmes (ALMPs) contribute to upward wage pressure in the Swedish economy. Most studies on aggregate…

Abstract

A number of earlier studies have examined whether extensive labour market programmes (ALMPs) contribute to upward wage pressure in the Swedish economy. Most studies on aggregate data have concluded that they actually do. In this paper we look at this issue using more recent data to check whether the extreme conditions in the Swedish labour market in the 1990s and the concomitant high levels of ALMP participation have brought about a change in the previously observed patterns. We also look at the issue using three different estimation methods to check the robustness of the results. Our main finding is that, according to most estimates, ALMPs do not seem to contribute significantly to an increased wage pressure.

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Accounting for Worker Well-Being
Type: Book
ISBN: 978-1-84950-273-3

Book part
Publication date: 6 January 2016

Jens H. E. Christensen and Glenn D. Rudebusch

Recent U.S. Treasury yields have been constrained to some extent by the zero lower bound (ZLB) on nominal interest rates. Therefore, we compare the performance of a standard…

Abstract

Recent U.S. Treasury yields have been constrained to some extent by the zero lower bound (ZLB) on nominal interest rates. Therefore, we compare the performance of a standard affine Gaussian dynamic term structure model (DTSM), which ignores the ZLB, to a shadow-rate DTSM, which respects the ZLB. Near the ZLB, we find notable declines in the forecast accuracy of the standard model, while the shadow-rate model forecasts well. However, 10-year yield term premiums are broadly similar across the two models. Finally, in applying the shadow-rate model, we find no gain from estimating a slightly positive lower bound on U.S. yields.

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Dynamic Factor Models
Type: Book
ISBN: 978-1-78560-353-2

Keywords

Abstract

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Applying Maximum Entropy to Econometric Problems
Type: Book
ISBN: 978-0-76230-187-4

Abstract

Details

New Directions in Macromodelling
Type: Book
ISBN: 978-1-84950-830-8

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