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Article
Publication date: 20 January 2023

Sakshi Soni, Ashish Kumar Shukla and Kapil Kumar

This article aims to develop procedures for estimation and prediction in case of Type-I hybrid censored samples drawn from a two-parameter generalized half-logistic…

Abstract

Purpose

This article aims to develop procedures for estimation and prediction in case of Type-I hybrid censored samples drawn from a two-parameter generalized half-logistic distribution (GHLD).

Design/methodology/approach

The GHLD is a versatile model which is useful in lifetime modelling. Also, hybrid censoring is a time and cost-effective censoring scheme which is widely used in the literature. The authors derive the maximum likelihood estimates, the maximum product of spacing estimates and Bayes estimates with squared error loss function for the unknown parameters, reliability function and stress-strength reliability. The Bayesian estimation is performed under an informative prior set-up using the “importance sampling technique”. Afterwards, we discuss the Bayesian prediction problem under one and two-sample frameworks and obtain the predictive estimates and intervals with corresponding average interval lengths. Applications of the developed theory are illustrated with the help of two real data sets.

Findings

The performances of these estimates and prediction methods are examined under Type-I hybrid censoring scheme with different combinations of sample sizes and time points using Monte Carlo simulation techniques. The simulation results show that the developed estimates are quite satisfactory. Bayes estimates and predictive intervals estimate the reliability characteristics efficiently.

Originality/value

The proposed methodology may be used to estimate future observations when the available data are Type-I hybrid censored. This study would help in estimating and predicting the mission time as well as stress-strength reliability when the data are censored.

Details

International Journal of Quality & Reliability Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0265-671X

Keywords

Article
Publication date: 27 December 2022

Bright Awuku, Eric Asa, Edmund Baffoe-Twum and Adikie Essegbey

Challenges associated with ensuring the accuracy and reliability of cost estimation of highway construction bid items are of significant interest to state highway…

Abstract

Purpose

Challenges associated with ensuring the accuracy and reliability of cost estimation of highway construction bid items are of significant interest to state highway transportation agencies. Even with the existing research undertaken on the subject, the problem of inaccurate estimation of highway bid items still exists. This paper aims to assess the accuracy of the cost estimation methods employed in the selected studies to provide insights into how well they perform empirically. Additionally, this research seeks to identify, synthesize and assess the impact of the factors affecting highway unit prices because they affect the total cost of highway construction costs.

Design/methodology/approach

This paper systematically searched, selected and reviewed 105 papers from Scopus, Google Scholar, American Society of Civil Engineers (ASCE), Transportation Research Board (TRB) and Science Direct (SD) on conceptual cost estimation of highway bid items. This study used content and nonparametric statistical analyses to determine research trends, identify, categorize the factors influencing highway unit prices and assess the combined performance of conceptual cost prediction models.

Findings

Findings from the trend analysis showed that between 1983 and 2019 North America, Asia, Europe and the Middle East contributed the most to improving highway cost estimation research. Aggregating the quantitative results and weighting the findings using each study's sample size revealed that the average error between the actual and the estimated project costs of Monte-Carlo simulation models (5.49%) performed better compared to the Bayesian model (5.95%), support vector machines (6.03%), case-based reasoning (11.69%), artificial neural networks (12.62%) and regression models (13.96%). This paper identified 41 factors and was grouped into three categories, namely: (1) factors relating to project characteristics; (2) organizational factors and (3) estimate factors based on the common classification used in the selected papers. The mean ranking analysis showed that most of the selected papers used project-specific factors more when estimating highway construction bid items than the other factors.

Originality/value

This paper contributes to the body of knowledge by analyzing and comparing the performance of highway cost estimation models, identifying and categorizing a comprehensive list of cost drivers to stimulate future studies in improving highway construction cost estimates.

Details

Engineering, Construction and Architectural Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 5 May 2015

Steven Stelk, Sang Hyun Park and Michael T Dugan

This paper aims to identify the more accurate method of estimating a firm’s degree of operating leverage (DOL) between two popular DOL estimation techniques: that proposed…

606

Abstract

Purpose

This paper aims to identify the more accurate method of estimating a firm’s degree of operating leverage (DOL) between two popular DOL estimation techniques: that proposed by Mandelker and Rhee (M&R), and that proposed by O’Brien and Vanderheiden (O&V).

Design/methodology/approach

O’Brien and Vanderheiden argue that M&R measure growth in operating earnings relative to the growth in sales rather than DOL. The authors estimate the relative growth estimate, RGE, from the O&V technique (operating earnings growth rate/sales growth rate) and compare this with the DOL estimates from the M&R technique to see if they are similar.

Findings

The authors find that the DOL estimates from the M&R method are indistinguishable from the relative growth estimates from the O&V method, providing the first direct evidence that O&V’s critique is correct. The M&R DOL estimates primarily measure the growth in operating earnings relative to the growth in sales, not DOL.

Originality/value

A firm’s DOL is a determinant of its common stock’s systematic risk, which determines a firm’s equity cost of capital. The equity cost of capital is a fundamental part of capital budgeting, capital structure and stock price analysis. Accurately estimating a firm’s DOL is important to researchers and corporate financial managers. Existing diversity in DOL estimation techniques raises questions about the validity of various techniques and limits comparability of existing studies. This paper demonstrates why the O&V technique should be used in place of the M&R method.

Details

Journal of Financial Economic Policy, vol. 7 no. 2
Type: Research Article
ISSN: 1757-6385

Keywords

Article
Publication date: 1 February 1996

MICHAEL K. JUDIESCH, FRANK L. SCHMIDT and MICHAEL K. MOUNT

Recently, we (Judiesch, Schmidt, & Mount, 1992) concluded that the Schmidt et al. (1979) SDy estimation procedure results in downwardly biased estimates of utility. This…

Abstract

Recently, we (Judiesch, Schmidt, & Mount, 1992) concluded that the Schmidt et al. (1979) SDy estimation procedure results in downwardly biased estimates of utility. This conclusion led us to propose a modification of the Schmidt et al. method that involves estimating SDy as the product of estimates of the coefficient of variation (SDy/ Y) and an objective estimate of the average value of employee output (Y). The present article reviews the rationale underlying our conclusion that this modification of the Schmidt et al. method of estimating SDy results in more accurate estimates of SDy, and hence, utility.

Details

Journal of Human Resource Costing & Accounting, vol. 1 no. 2
Type: Research Article
ISSN: 1401-338X

Article
Publication date: 25 January 2008

Young Hoon Kwak, Rudy J. Watson and Frank T. Anbari

This paper is a summary of a successfully defended doctoral dissertation. The purpose of this paper is to place this research in context to emerging areas of project…

Abstract

Purpose

This paper is a summary of a successfully defended doctoral dissertation. The purpose of this paper is to place this research in context to emerging areas of project management and service science, management and engineering and to encourage others to embark on further research related to this important topic.

Design/methodology/approach

Results reported in this paper were based upon action learning from research in which a project management tool for estimating deployment cost was developed by capturing the knowledge of subject matter experts (SMEs) and subsequently tested against projects from various geographic areas.

Findings

There were two primary findings. A development and analysis of the conceptual estimating framework supports the assertion that the use of the framework provides an awareness of the project that may not otherwise be observed or, at best, would be observed later in the life of the project and potentially addressed at a higher cost. A strong association has been found between the conceptual estimate produced by the comprehensive framework and the conceptual estimate produced manually through the use of SMEs.

Originality/value

From academic perspective, the synthesis of technology management, business processes, and the conceptual estimating framework enhances the body of knowledge of project management. For practical applications, the method and framework employed can be utilized to build functioning conceptual estimating tools for deployment, which can lead to cost savings during the estimating process and, as this study surmises, will lead to more effective project management, control, and implementation.

Details

International Journal of Managing Projects in Business, vol. 1 no. 1
Type: Research Article
ISSN: 1753-8378

Keywords

Article
Publication date: 1 February 2001

Stephen Hunt and Lynn J. Frewer

Perceptions of trust have been identified as an important element in the risk communication process. This research is concerned with establishing the degree of trust the…

1954

Abstract

Perceptions of trust have been identified as an important element in the risk communication process. This research is concerned with establishing the degree of trust the general public has in various possible sources of information about the health effects associated with consuming genetically modified food. Participants were asked directly about the degree to which they would trust information about the health effects associated with consuming genetically modified food from a variety of sources, including a fictitious source included as a control. They were also asked about the degree to which they believed each source had a vested interest in misinforming the public about the possible health effects associated with such consumption, and the degree of knowledge they believed each source had about any possible health effects. The results indicate that perceptions of “vested interest” and “degree of knowledge” are important elements in determining levels of trust, although probably not exhaustive. Furthermore, that younger consumers are likely to be the most responsive audience for risk information, but general audience response to risk information is likely to be influenced by preconceptions about the source of the information, preconceptions that can be derived entirely from the name of the information source.

Details

British Food Journal, vol. 103 no. 1
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 1 February 1996

DANIEL V. LEZOTTE, NAMBURY S. RAJU, MICHAEL J. BURKE and JACQUES NORMAND

This study compared per selectee utility estimates for the job of medical claims examiner based on applications of the Brogden‐Cronbach‐Gleser (BCG) and Raju‐Burke‐Normand…

Abstract

This study compared per selectee utility estimates for the job of medical claims examiner based on applications of the Brogden‐Cronbach‐Gleser (BCG) and Raju‐Burke‐Normand (RBN) utility analysis models. The RBN model's per selectee utility estimate, based on a transformed observed performance rating standard deviation (σR), was closest to the per selectee utility estimate computed with an empirically‐derived σY value. The implications of these results for estimating human resource program utility are discussed.

Details

Journal of Human Resource Costing & Accounting, vol. 1 no. 2
Type: Research Article
ISSN: 1401-338X

Book part
Publication date: 15 January 2010

Sean M. Puckett and John M. Rose

Currently, the state of practice in experimental design centres on orthogonal designs (Alpizar et al., 2003), which are suitable when applied to surveys with a large…

Abstract

Currently, the state of practice in experimental design centres on orthogonal designs (Alpizar et al., 2003), which are suitable when applied to surveys with a large sample size. In a stated choice experiment involving interdependent freight stakeholders in Sydney (see Hensher & Puckett, 2007; Puckett et al., 2007; Puckett & Hensher, 2008), one significant empirical constraint was difficult in recruiting unique decision-making groups to participate. The expected relatively small sample size led us to seek an alternative experimental design. That is, we decided to construct an optimal design that utilised extant information regarding the preferences and experiences of respondents, to achieve statistically significant parameter estimates under a relatively low sample size (see Bliemer & Rose, 2006).

The D-efficient experimental design developed for the study is unique, in that it centred on the choices of interdependent respondents. Hence, the generation of the design had to account for the preferences of two distinct classes of decision makers: buyers and sellers of road freight transport. This paper discusses the process by which these (non-coincident) preferences were used to seed the generation of the experimental design, and then examines the relative power of the design through an extensive bootstrap analysis of increasingly restricted sample sizes for both decision-making classes in the sample. We demonstrate the strong potential for efficient designs to achieve empirical goals under sampling constraints, whilst identifying limitations to their power as sample size decreases.

Details

Choice Modelling: The State-of-the-art and The State-of-practice
Type: Book
ISBN: 978-1-84950-773-8

Book part
Publication date: 13 October 2008

George Miller, Charles Roehrig, Paul Hughes-Cromwick and Craig Lake

Purpose: We estimate national health expenditures on prevention using precise definitions, a transparent methodology, and a subdivision of the estimates into components to…

Abstract

Purpose: We estimate national health expenditures on prevention using precise definitions, a transparent methodology, and a subdivision of the estimates into components to aid researchers in applying their own concepts of prevention activities.

Methodology/Approach: We supplemented the National Health Expenditure Accounts (NHEA) with additional data to identify national spending on primary and secondary prevention for each year from 1996 to 2004 across eight spending categories.

Findings: We estimate that NHEA expenditures devoted to prevention grew from $83.2 billion in 1996 to $159.8 billion in 2004, in current dollars. As a share of NHEA, this represents an increase from 7.8 percent in 1996 to 8.6 percent in 2004. This share peaked at 9 percent in 2002 and then declined due to reductions in public health spending as a percent of NHEA between 2002 and 2004. Primary prevention represents about half the expenditures, consisting largely of public health expenditures – the largest prevention element.

Originality/Value of Paper: Our 2004 estimate that 8.6 percent of NHEA goes to prevention is nearly three times as large as the commonly cited figure of 3 percent, but depends on the definitions used: our estimate falls to 8.1 percent when the research component is excluded, 5.1 percent when consideration is limited to primary prevention plus screening, 4.2 percent for primary prevention alone, and 2.8 percent if we count only public health expenditures. These findings should contribute to a more informed discussion of our nation's allocation of health care resources to prevention.

Details

Beyond Health Insurance: Public Policy to Improve Health
Type: Book
ISBN: 978-1-84855-181-7

Book part
Publication date: 1 November 2007

Irina Farquhar and Alan Sorkin

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized…

Abstract

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.

Details

The Value of Innovation: Impact on Health, Life Quality, Safety, and Regulatory Research
Type: Book
ISBN: 978-1-84950-551-2

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