48 research outputs found
DYNAMIC NETWORK RANGE-ADJUSTED MEASURE VS. DYNAMIC NETWORK SLACKS-BASED MEASURE
We dedicate this paper to the memory of Professor William W. Cooper, 1914–2012, whose generous demeanor touched and inspired at least three generations of DEA researchers. It is up to the DEA community to make sure that his vision and legacy live on. Abstract We formulate weighted, dynamic network range-adjusted measure (DN-RAM) and dynamic network slacks-based measure (DN-SBM), run robustness tests and compare results. To the best of our knowledge, the current paper is the first to compare two weighted dynamic network DEA models and it also represents the first attempt at formulating DN-RAM. We illustrate our models using simulated data on residential aged care. Insight gained by running DN-RAM in parallel with DN-SBM includes (a) identical benchmark groups, (b) a substantially wider range of efficiency estimates under DN-RAM, and (c) evidence of inefficient size bias. DN-RAM is also shown to have the additional desirable technical efficiency properties of translation-invariance and acceptance of free data. Managerial implications are also briefly discussed
The influence of co-authorship on article impact in OR/MS/OM and the exchange of knowledge with Finance in the twenty-first century
This article is motivated by two related research questions about research activity in the Operations Research/Management Science/Operations Management (OR/MS/OM) and Finance disciplines. First, we investigate the influence of co-authorship on article impact in OR/MS/OM. Second, we develop a number of citation metrics to explore the nature of scholarly exchange between top OR/MS/OM and Finance journals. We work with a large sample of articles published across 2001–2008 for twenty OR/MS/OM journals and nineteen Finance journals, with corresponding citations up to and including year 2012. Key findings from the first research question indicate a higher impact for articles with multiple authors, but with the marginal gain brought by an additional author being insignificant for articles with three or more authors. For the second research question, we find that the Finance discipline borrows less from OR/MS/OM than vice versa, which highlights the potential for wider collaboration among researchers—particularly for Finance academics in exploring how various OR/MS/OM techniques can be adopted or adapted into their research. Finally, we discover that the ranking of OR/MS/OM journals is determined more by the extent that they are cited in other disciplines, but observe a gradual rise in self-perpetuating behavior in the OR/MS/OM discipline
Crystal structure and Hirshfeld surface analysis of 2-{[(E)-(3-cyclo butyl-1H-1,2,4-triazol-5-yl)imino] meth yl}phenol
The title compound, C13H14N4O, was developed using the reaction of salicyl aldehyde and 3-amino-5-cyclo butyl-1,2,4-triazole in ethanol under microwave irradiation. This eco-friendly microwave-promoted method proved to be efficient in the synthesis of 2-{[(E)-(3-cyclo butyl-1H-1,2,4-triazol-5-yl)imino] meth yl}phenol in good yields and purity. The title compound is a Schiff base that exists in the phenol-imine tautomeric form and adopts an E configuration. The three independent mol ecules in the asymmetric unit (A, B and C) are not planar, the cyclo butyl and the phenol-imine rings are twisted to each other making a dihedral angle of 67.8 (4)° in mol ecule A, 69.1 (2)° in mol ecule B and 89.1 (2)° in mol ecule C. In each mol ecule an intra molecular O - H⋯N hydrogen bond is present, forming an S(6) ring motif. A Hirshfeld surface analysis was performed to investigate the contributions of the different inter molecular contacts within the supra molecular structure. The major inter actions are H⋯H (53%), C⋯H (19%) and N⋯H (17%) for mol ecule A, H⋯H (50%), N⋯H (20%) and C⋯H (20%) for mol ecule B and H⋯H (57%), C⋯H (14%) and N⋯H (13%) for mol ecule C
Crystal structure and Hirshfeld surface analysis of 3-(hydroxymethyl)-3-methyl-2,6-diphenylpiperidin-4-one
A new synthesis of the title compound, C19H21NO2, was developed with good yield and purity using the reaction of 4-hydroxy-3-methyl-2-butanone, benzaldehyde and ammonium acetate in glacial acetic acid as a solvent. The central piperidine ring adopts a chair conformation, and its least-squares basal plane forms dihedral angles of 85.71 (11) and 77.27 (11)° with the terminal aromatic rings. In the crystal, the molecules are linked by O-H⋯O and C-H⋯O hydrogen bonds into double ribbons. The Hirshfeld surface analysis shows that the most important contributions are from H⋯H (68%), C⋯H/H⋯C (19%) and O⋯H/H⋯O (12%) interactions
Crystal structure and Hirshfeld surface analysis of two 5,11-methanobenzo[g][1,2,4]triazolo[1,5 c][1,3,5]oxadiazocine derivatives
In the title compounds, 9-bromo-2,5-dimethyl-11,12-dihydro-5H-5,11-methanobenzo[g][1,2,4]triazolo[1,5-c][1,3,5]oxadiazocine, C13H13BrN4O (I), and 7-methoxy-5-methyl-2-(pyridin-4-yl)-11,12-dihydro-5H-5,11-methanobenzo[g][1,2,4]triazolo[1,5-c][1,3,5]oxadiazocine, C18H17N5O2 (II), the triazole ring is inclined to
the benzene ring by 85.15 (9) and 76.98 (5) in compounds I and II, respectively.
In II, the pyridine ring is almost coplanar with the triazole ring, having a dihedral
angle of 4.19 (8). In the crystal of I, pairs of N—HN hydrogen bonds link the
molecules to form inversion dimers with an R2
2
(8) ring motif. The dimers are
linked by C—H and C—Br interactions forming layers parallel to the bc
plane. In the crystal of II, molecules are linked by N—HN and C—HO
hydrogen bonds forming chains propagating along the b-axis direction. The
intermolecular interactions were investigated using Hirshfeld surface analysis
and two-dimensional fingerprint plots, and the molecular electrostatic potential
surface was also analysed. The Hirshfeld surface analysis of I suggests that the
most significant contributions to the crystal packing are HH (42.4%) and
OH/HO (17.9%) contacts. For compound II, the HH (48.5%), CH/
HC (19.6%) and NH/HN (16.9%) interactions are the most important
contributions.The authors acknowledge the Faculty of Arts and Sciences, Ondokuz Mayis University, Turkey, for the use of the Stoe IPDS 2 diffractometer (purchased under grant F. 279 of the University Research Fund) and the Council of Higher Education of Turkey, Mevlana Exchange Program (MEV-2016-027)
Suitability between interior housing equipments and technological devices and its effect on user satisfaction
Bu çalışmada, konutlarda bulunan iç mekân donatı elemanları ile bir arada kullanılan; ankastre ocak, fırın, bilgisayar, televizyon vb. teknolojik ürünlerin boyutsal standartlar açısından ilişkilerinde kullanıcıların karşılaştığı sorunların tespit edilmesi amaçlanmıştır. Bu amaçla, hazırlanmış olan araştırma anketi Ankara’nın Çiğdem Mahallesi bölgesinde yaşayan üst sosyoekonomik düzeye (SED) sahip 128 konut kullanıcısına uygulanmış olup, elde edilen veriler istatistiksel yöntemlerle değerlendirilmiştir. Buna göre, konut kullanıcılarının önemli bir kısmının teknolojik ürünler ile donatı elemanları arasındaki ilişkiden memnun olmadıkları, bu memnuniyetsizliğin başta proje/tasarım hataları olmak üzere ölçü ve imalat hatalarından kaynaklandığı tespit edilmiş ve sonuçta üreticilerin teknolojiyi yeterince takip edemedikleri ortaya çıkmıştır.This research aims to determine the difficulties that the users might be experiencing with dimensional standards of
interior housing equipments in connection with the technological devices such as built-in cooker, oven, computer, television, etc.
For that aim, the prepared research questionnaire was conducted on 128 residents of high socio-economic status (SES) who live
in Çiğdem Mahallesi which is one of the suburbs in the south of Ankara. According to the statistical analysis, it was concluded
that the majority of the residents were unhappy due to the mismatch between the interior housing equipments and the
technological devices. The unhappiness was mainly due to the project/design errors along with scaling and production faults, and
the inadequate use of technology by the producers
Missed Opportunities for Coronary Heart Disease Diagnoses: Primary Care Experience
Cilj Istražiti propuštene prilike da se u primarnoj zdravstvenoj zaštiti otkriju postojeće koronarne srčane bolesti koje prethodno nisu bile dijagnosticirane i rizične čimbenike koji su povezani s njima. Methods Istraživanje je obuhvatilo 850 osoba starijih od 30 godina, koji u povijesti bolesti nisu imali koronarnu srčanu bolest, a bili su pacijenti centra primarne zdravstvene zaštite u prigradskom dijelu grada Antalya u Turskoj. Prikupili smo podatke o njihovoj dobi, spolu, stupnju izobrazbe, zdravstvenom osiguranju, prihodima, pušenju i fizičkim aktivnostima. Pacijente s nedijagnosticiranom koronarnom srčanom bolešću otkrili smo s pomoću Roseova upitnika, fizikalnim pregledom i elektrokardiogramom. Mjerili smo im visinu, težinu, krvni tlak, serumsku koncentraciju glukoze i kolesterola, a indeks tjelesne težine i omjer opsega struka i bokova smo izračunali. Svakom je pacijentu dodijeljen broj bodova za rizične čimbenike koji su uključivali dob, spol, pušenje, sistolički krvani tlak i koncentraciju kolesterola. Za svakoga je pojedinca izračunat rizik da u sljedećem desetljeću razvije koronarnu srčanu bolest. Rezultati Bilo je 126 (14.8%) prethodno nedijagnosticiranih slučajeva nedijagnosticirane koronarne srčane bolesti. Ukupni srednji (±standardna devijacija) broj bodova za rizik dobivanja koronarne srčane bolesti u sljedećem desetljeću bio je 6.1±6.8. Bolesti koje potiču razvitak koronarne srčane bolesti – hipertenzije, šećerne bolesti i hiperkolesterolemije otkrivene su u 255 (30.4%), odnosno u 70 (8.2%) i u 364 (43.4%) ispitanika. Debljina je utvrđena u 315 (37.1%) ispitanika, a 222
(26.1%) su bili pušači. Za osobe koje se koriste primarnom zdravstvenom zaštitom procijenjeni postotni rizik za razvitak koronarne srčane bolesti u sljedećem desetljeću bio je 7 do 45% za
muškarce i 2 do 45% za žene. Zaključak U primarnoj se zdravstvenoj zaštiti propušta prilika za bolje otkrivanje koronarne srčane bolesti kao i topoglednih rizičnih čimbenika. Potrebno je poduzeti mjere da se oni na vrijeme otkrivaju.Aim To investigate missed opportunities to reveal existing but not formerly diagnosed coronary heart disease cases and related risk factors in primary health care. Methods The study comprised 850 people aged over 30 years with no known history of coronary heart disease, receiving health services from a primary care center located in a suburban area of Antalya, Turkey. Data on their age, gender, education level, health insurance status, income, smoking behavior, and physical activities were collected. Undiagnosed coronary heart disease patients were determined by the Rose questionnaire, physical examination, and electrocardiogram. Height and weight, blood pressure, serum glucose and cholesterol levels were measured, and body-mass index and waist-hip ratio calculated. Each
patient was given a risk score regarding age, smoking behavior, tolic
blood pressure, and cholesterol levels. Estimated risk ratio of each
person for developing coronary heart disease in the next decade was
determined. Results The number of formerly undiagnosed coronary heart disease cases was 126 (14.8%). Overall mean (±standard deviation) risk score for developing coronary heart disease in the next decade in study group was 6.1 ± 6.8. Diseases facilitating development of coronary heart disease: hypertension, diabetes, and hypercholesterolemia were present in 255 (30.4%), 70 (8.2%), and 364 (43.4%) participants, respectively. Obesity was detected in 315 (37.1%) subjects and there were 222 (26.1%) current smokers. For patients who attended primary health care, the estimated percentage risk for developing coronary heart disease in the next ten years was 7 to 45% in men and 2 to 45% in women. Conclusion Opportunities to reveal coronary heart disease and its risk factors are being missed in primary care. Measures should be taken to ensure timely diagnosis of coronary heart disease and related risk factors
BRIDGING RADIAL AND NON-RADIAL MEASURES OF EFFICIENCY IN DEA
Data envelopment analysis (DEA) has been utilized worldwide for measuring efficiencies of banks, telecommunications, electric utilities and so forth. Yet, the existing models have some well known shortcomings that limit their usefulness. In DEA we have two fundamental approaches to measuring efficiency with very different characteristics; radial and non-radial. We demonstrate a method for linking these two approaches in a unified framework called Connected-SBM. It includes two scalar parameters, and by changing the parameter values we can relocate the analysis anywhere between the radial and the non-radial models. An appropriate choice of these parameters can overcome the key shortcomings inherent in the two approaches, namely, proportionality and mixed patterns of slacks.http://www.grips.ac.jp/list/facultyinfo/tone_kaoru
Probing organizational efficiency
Purpose: In investigating the performance of multidivisional organizations, ability to account for each division's importance and contribution enhances the deftness of resource allocation and targeting desired outcomes. With this motivation, the author aims to introduce network data envelopment analysis (NDEA) from operations research in this conceptual article and discuss how two articles from this journal can be extended using this approach. Design/methodology/approach: NDEA was first developed to deliver a more in-depth understanding of underlying sources of operational inefficiency. Thus, NDEA can be viewed as a peer benchmarking method useful in comparing performance of organizations and identifying divisional inefficiencies that may detract from overall performance. NDEA's ability to capture interactions among multiple variables in an objective manner based on actual observed data rather than sample averages is one of its key advantages. Findings: The author discusses how NDEA can be applied in organisational analysis by examining two articles from this journal. Briefly commenting on one of the cases here, the author shows that a network can be defined as the interacting divisions of cultural norms and structural forms. The potential improvements (i.e. horizontal re-alignment) indicated by NDEA can guide management on the extent organisational alignment that could be changed in reaching strategic aims. The author's theoretical model is conducive to assessing the amount and direction of change from the proposed alignment model in a multi-criteria framework - characteristics embraced by NDEA. Practical implications: Given the hierarchical nature of organizations where employees are nested in work groups or teams, groups nested in departments or divisions, and divisions nested in organizations, application of NDEA at various levels of analysis is feasible. Originality/value: NDEA's ability to account for each division's importance or assign desired weights in what-if analyses adds to flexibility in managerial decision-making regarding allocation of resources, or re-alignment of processes and targeting of desired outcomes. Such a method that does not assume independence among multiple performance measures provides additional assurance to those concerned about shortcomings of additive scales in complex organizations
An in-depth discussion and illustration of partial least squares structural equation modeling in health care
Partial least squares structural equation modeling (PLS-SEM) has become more popular across many disciplines including health care. However, articles in health care often fail to discuss the choice of PLS-SEM and robustness testing is not undertaken. This article presents the steps to be followed in a thorough PLS-SEM analysis, and includes a conceptual comparison of PLS-SEM with the more traditional covariance-based structural equation modeling (CB-SEM) to enable health care researchers and policy makers make appropriate choices. PLS-SEM allows for critical exploratory research to lay the groundwork for follow-up studies using methods with stricter assumptions. The PLS-SEM analysis is illustrated in the context of residential aged care networks combining low-level and high-level care. Based on the illustrative setting, low-level care does not make a significant contribution to the overall quality of care in residential aged care networks. The article provides key references from outside the health care literature that are often overlooked by health care articles. Choosing between PLS-SEM and CB-SEM should be based on data characteristics, sample size, the types and numbers of latent constructs modelled, and the nature of the underlying theory (exploratory versus advanced). PLS-SEM can become an indispensable tool for managers, policy makers and regulators in the health care sector