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Considering ecological issues in supplier evaluation and management alongside business considerations is getting more recognition among firms. Data envelopment analysis (DEA) is one of those methods, which is frequently suggested by the literature to support management decisions. However, the data requirements of the method should be an important consideration. The literature often addresses the issue of desirable outputs and undesirable input as an important data related problem in case of the ecological use of DEA. This paper will present a new solution to manage these data problems along with connecting the evaluation of management criteria, environmental criteria and total cost aspects. The proposed environmental supplier selection problem is an extension of a former paper. The new model examines the effect of inventory related costs, such as EOQ costs of inventory holding or ordering costs on the selected supplier, extended with newly introduced scaled values of input and output indicators. The usage of scaled values is motivated by the problem of invariance to data alteration. In addition to the uncertainty of the data, the paper looks for a functional relationship between the input and output criterion values and the efficiency that can be assigned to them using DEA.

The paper investigates an one-product reverse logistics system. The aim is to analyze the functioning of such a system with continuous time and linear cost structure. The costs consist of linear holding costs for both warehouse, and the linear remanufacturing, manufacturing, and disposal costs. The demand and return rates are known deterministic parameters. The problem is solved with the Pontyagin’s maximum principle. Solving the control problem, it is corrected an earlier paper [1].

Using situation-specific and dyadic data, we analyse how trust in inter-organisational relationships evolve over time. Based on a multidisciplinary approach, we define four trust-related concepts, which include both behavioural and perceptual aspects of this multifaceted phenomenon. We also develop the hypothesis that the behavioural consistency of the trustee affects the level of his/her trustworthiness as perceived by the trustor. To test this hypothesis, the paper specifies a finite Dynamic Trust Game that, in a unique way, models longer-term relationships characterised by interdependent actions between partners. In contrast to the simple Repeated Games modelling discrete exchange episodes, this game corresponds to the requirements of the interaction approach of the relationship management, since the iterations of the game are interrelated and embedded in previous ones. Timely development of the behavioural variables in the game reflects an inverse U-shape with an increasing willingness to cooperate until round 8, with a maximum cooperation level of 80% on average. Behaviour seems to affect the perceived level of trustworthiness. However, we need additional experimental data on inconsistent behaviours to get a clear understanding of this effect.

The selection of input and output items is crucial for successful application of Data Envelopment Analysis (DEA) as they should express the decision maker's preferences and perceptions of what might affect the efficiency of a decision making unit (DMU). This article addresses the question of the transformation of input and output data that may be required for efficiency analyses using DEA method. Different methods for the data transformation are available in the literature, however, they may lead to different results, which may bias the decisions. This paper attempts to provide some guidance on this issue and to compare the results. An example of supplier evaluation will be used to illustrate the possible solutions and the differences in the final results (supplier evaluated to be among the efficient suppliers).

The Network Readiness Index (NRI) is one of the indicators that shows the level of digital development of countries. The NRI for 2021 shows the development of 130 countries, in contrast to the 45 countries covered by the International Digital Economy and Society Index (I-DESI) of the European Union, which measures only the most developed countries. This paper aims to determine the relationship between 12 sub-pillars of NRI. We use Principal Component Analysis (PCA) to perform a mapping of our data to a lower-dimensional space, and further analyse the causal relationships between the principal sub-pillars using partial correlation coefficients, concluding that two of the twelve main sub-pillars can be explained by ten independent sub-pillars. Thereafter, we use cluster analysis to group our objects (i.e. the 130 countries) into clusters.

A tanulmány célja az Európai Bizottság által készített nemzetközi digitális gazdaság és társadalom index (international digital economy and society index, I-DESI) dimenzióinak elemzése többváltozós statisztikai módszerekkel. A szerzők az EU- (Európai Unió) tagállamok és az EU-n kívüli országok adatainak szétválaszthatóságát diszkriminanciaanalízissel vizsgálják, a dimenziók értékeinek átlagát varianciaanalízissel hasonlítják össze. A dimenziók közötti korrelációt Pearsonféle és parciális korrelációs együtthatók alapján számítják, az összefüggéseket oksági láncon ábrázolják. Főkomponens-elemzés segítségével az öt dimenziót két főkomponensre vezetik vissza és az előző évi adatokhoz viszonyítva értelmezik. A kiugró adatokat a Mahalanobis-távolságokkal értékelik. Eredményeik alátámasztják az Európai Bizottság álláspontját a digitális gazdaság vizsgált dimenziónak szoros összefüggéséről, valamint azt, hogy nincs jelentős különbség az EU-tagállamok és az EU-n kívüli országok között.

A cikk a szennyezési jogok bevezetését vizsgálja a mikroökonómia standard vállalatára. A komparatív statika módszerével vizsgáljuk a termelő vállalat lehetséges reakcióit a szennyezési jog bevezetésére. A vállalatok stratégiája a szennyezési jog bevezetésére a technológia változatlanul hagyása, vagy megváltoztatása lehet. Az egyes esetekben arra keresünk választ, hogy hogyan változik a vállalat nyeresége a bevezetés előtti állapothoz képest, és ez milyen szennyezési stratégiával jár. Szennyezési jogot elad-e, vagy vesz a vállalat a szennyezési jogok piacán? = The paper deals with the effect of an introduction of tradable permits on the production strategy of a firm. It is assumed that the firm will maximize its profit. After introducing the emission trading the profit function will contain the linear emission procurement/selling costs. We will compare the optimal production strategy before tradable permits and after that. The mathematical investigation is based on the nonlinear mathematical programming.

A világ egyetemeinek rangsorai azzal a céllal jöttek létre, hogy a felsőoktatási intézmények teljesítményét, valamint az intézmények minőségét mérjék. Az ilyen listák a felsőoktatási piacra jelentkezők számára nyújtanak támpontot, de az egyes államok döntéshozóinak is fontos információforrása lehet arról, hogy a nemzetközi tudományos versenyképesség területén az országok felsőoktatási intézményei miként teljesítenek. Számos ilyen rangsor létezik. A szerzők célja, hogy a kiválasztott Quacquarelli Symonds (QS) World University Rankings 2021-et és a rangsorba felvett egyetemeket az Elsevier kiadó által létrehozott Scopus- és SciVal-adatbázisokból nyert statisztikai változók alapján megvizsgálják. Tehát nem a sorrendképzés a cél, hanem a QS-rangsorba felvett egyetemek statisztikai változóinak, kritériumainak többváltozós statisztikai elemzése. Az eredmények szerint – amelyek nagyfokú hasonlóságot mutatnak – a Scopus/SciVal adatai alapján nemcsak a kutatók, hanem az egyetemek teljesítményét is fel lehet mérni.

A tanulmany hat orszag (Ausztria, Csehorszag, Lengyelorszag, Magyarorszag, Romania es Szlovakia) gazdasagtudomanyi kutatoinak Scopus-adatbazisban megtalalhato publikacios teljesitmenyet es az altaluk kivaltott szamszerűsitett hatasokat (peldaul hivatkozasokat) elemzi. Empirikus kutatasunk eredmenyekent megallapithato, hogy a hat orszag gazdasagtudomanyi kutatoi vilagos publikacios strategiaval rendelkeznek, a publikaciok szamanak novelesere koncentralnak, mikozben intenziven torekszenek arra, hogy tudomanyos eredmenyeiket tarsszerzős kozlemenyekkent is kozreadjak. A hivatkozasok szamat a kozlemenyek szamaval es a tarsszerzőszam novelesevel bővitik, amely a Hirsch-indexuket is kedvezően befolyasolja. A publikacios teljesitmeny alapjan a visegradi negyek, valamint Ausztria es Romania vezető gazdasagtudomanyi kutatoi nem sorolhatoak tipikus csoportokba, az eredmenyek szorodasat vizsgalva ugyanis viszonylag homogen kozosseget alkotnak. A kutatoi rangsorok elmezőnyeben az osztrak, a lengyel es a cseh gazdasagtudomanyi kutatok talalhatok, mig a magyarok stabilan a masodik vonalban vannak, addig a szlovakok es a romanok leszakadva kovetik őket. = The paper analyses the publication performance and the received scientific impact (for instance, citations) of the Business and Economics researchers in six Central European countries, including Austria, the Czech Republic, Poland, Hungary, Slovakia, and Romania. The analysis is based on the Scopus citation database. Empirical findings demonstrate that Business and Economics researchers in these countries follow a wellestablished publication strategy, focusing on increasing the number of publications. Simultaneously, they tend to publish with coauthors to strengthen further the number of publications. Concerning the number of citations, it is raised by the increasing number of publications and by a wide coauthor network, which also affects their Hirsch index favourably. Regarding their publication performance, the leading Business and Economics researchers in the Visegrad Group of counties, Austria and Romania belong to no typical cluster, as the scatter plot shows a relatively homogenous community of these researchers. Our findings demonstrate that in the ranking of researchers, Austria, Poland and the Czech Republic dominate, Hungary is in a secondary line, while Slovakia and Romania are lagging behind.

The study analyses the publication performance of economics and management researchers in the Visegrad 4 countries (Czech Republic, Poland, Hungary, and Slovakia) and Romania based on their publications in the Scopus database. First, 150 researchers are selected from each country, who are then further selected according to their most recent affiliation and research area. Using a 449-item dataset, six multivariate statistical analyses (e.g. principal component analysis and cluster analysis) are carried out to examine the relationships among the seven variables (e.g. number of publications, citations, and co-authors) that characterize the performance of the publication activity of researchers. The results highlight the excellence criteria for the publication performance of economics and management researchers from the Visegrad 4 countries and Romania as well as their ranking position.

A szerzők a digitális gazdaság és társadalom index (digital economy and society index, DESI) öt alapdimenziója segítségével, de az önkényes, szubjektív súlyozáson (scoring modellen) alapuló kompozit index helyett objektívebb, az adatsorok statisztikai tulajdonságait felhasználó rangsorolási módszerekkel kívánnak választ adni arra a kérdésre, hogy Magyarország hol helyezkedik el a digitális fejlettséget tekintve az EU (Európai Unió) országai között. A rangsorolást az összetett indikátorok burkológörbe-elemzése (data envelopment analysis/composite indicators, DEA/CI) és az ideális megoldásokhoz hasonló preferenciarendszer technikája (technique for order of preference by similarity to ideal solution, TOPSIS) alkalmazásával végzik el, majd összehasonlítják az EU-s országok két döntéselméleti eljárással kapott rangsorát. A TOPSIS- és a DEA/CI-módszer előnye a hagyományos DEA-val szemben, hogy abban az esetben is adattranszformáció nélkül alkalmazhatók, ha az adatok között csak (maximalizálandó) outputkritériumok vannak, ezáltal elkerülhetők a transzformációval járó torzítások. Az eredményül kapott rangsorok alapján Magyarország az uniós országok második harmadában helyezkedik el, így közepes digitális fejlettségűnek tekinthető.

A 21. században az internet és a digitalizáció fejlődésével, széles körű elterjedésével olyan pozitív hatások érik a társadalmat, melyek kihatnak az élet minden területére. A tanulmány egy „fiatal” olimpiai sportág elemzését végzi, olyan új adatok feldolgozásával, amelyeket korábban elképzelni sem lehetett. A sportág szempontjából kiemelten fontos – hiszen a fennmaradáshoz, a fejlődéshez nélkülözhetetlen – a sportszakmai nóvum megtalálása. A digitalizációnak köszönhetően falmászók (n=125) eredményeit vizsgáltuk, akik különböző mászótermekben a forradalmasított Clift-okosmászófal rendszert használták. Az okosmászófal mérési adatai a biztonságos Clift-felhőben kerülnek tárolásra. Az adatgyűjtés ebből az adattárból történt. A statisztikai vizsgálatok (SPSS 26) a változók szerepét, fontosságát vizsgálták a sportág fejlődésének szempontjából.

This paper offers a solution to the supplier selection problem and the problem of lot‐sizing decisions. Data Envelopment Analysis (DEA) is seldom applied to help solve multilevel supplier selection problems. The order allocation problem is reformulated as a linear programming problem in a novel way. First, a Data Envelopment Analysis/common weights model (DEA/CWA) is introduced to help define the supplier pool of capable suppliers. Selection criteria include management and green criteria. In a second phase, a nonlinear mathematical programing model is offered to determine capacity distribution among selected suppliers. A numerical example is provided to support the theoretical model.

The use of international university rankings is an internationally recognized way of evaluating higher education systems and institutions. The QS ranking is one of the best-known among them, and it ranks institutions along six indicators. This study has two objectives. We first examine how the QS ranking and the university rankings derived from the variables obtained from the Scopus/SciVal database by the TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) ranking procedure relate to each other. We find that the QS ranking and the ranking obtained with the Scopus/SciVal data show strong similarity. The second goal was to test the place of the countries on the ranking. A comparison of universities from countries on the QS ranking led to the conclusion that the top-ten ranked countries were mainly smaller Western European countries as well as two city-states from the Far East. Our analysis can be considered somewhat unique as the method for calculating the data determining the QS rankings is not always available on the QS website, so the ranking cannot be repeated. In addition, the ranking results are only available once a year, so only the results of the most recent QS measurement are available between the two dates.

Significant differences exist among companies in terms of their green purchasing practices. One of the explanatory factors for the former is company size. This article examines how to capture relat...

Supplier evaluation is one of the most important fields of application for data envelopment analysis (DEA). Criteria may include negative data in both input and output factors. Data translation can solve this problem, but interpretation is not evident from the literature. Use of an additive model is one method of managing the problem of negative data. This paper addresses this issue in relation to the supplier ranking problem. It describes the development of a ranking with cross-efficiency that incorporates negative data into the additive model. The additive model we describe is compared with previously used DEA models in which data is replaced with reciprocal values when necessary. We present a supplier-evaluation-related example of this case. After the efficiency evaluation, a supplier ranking system is constructed. To do this, we use the cross-efficiencies obtained from the additive model. Aggregate efficiencies help display the suppliers in descending order of efficiency. Finally, the paper compares self- and peer-appraisal indicators for reciprocal and additive DEA models.

A kkv-k (kis- es kozepvallalatok) műkodese fontos temaja a gazdasagi szakirodalomnak, a megjelent munkak szamos aspektusbol elemzik jellemzőiket. Jelen tanulmany azt vizsgalja, hogy a kkv-k mint fogyasztok (vevők) mennyire kepesek beepiteni a kornyezeti tenyezőket a beszerzesi tevekenysegukbe. Bar a temaval szamos vallalati kutatas foglalkozik, azok zommel a nagyvallalatok sajatossagaira osszpontositanak. A szerzők celja eppen ezert az, hogy feltarjak, a kkv-k gyakorlata elter-e, s ha igen, milyen jellemzőiben a nagyvallatoketol. Elemzesukben, mely egy hazai kerdőives felmeres adatbazisara epul, előszor VIF (variance inflation factor – varianciainflacios tenyező) segitsegevel kiszűrik a kollinearis valtozokat, majd a megmaradtakra főkomponenselemzest vegeznek, es az eredmenyek osszefuggeseit vizsgaljak.

A tanulmany Kelet-Kozep-Europa (Csehorszag, Lengyelorszag, Magyarorszag, Romania es Szlovakia) gazdasagtudomanyi kutatoinak publikacios teljesitmenyet elemzi a 2009 es 2018 kozott megjelent es a Scopus-adatbazisban megtalalhato kozlemenyeik alapjan. A szerzők azokra a kerdesekre keresik a valaszt, hogy egyreszt mi tekinthető a kelet-kozep-europai gazdasagtudomanyi kutatoi kozossegben a sikeres publikacios strategia kulcstenyezőinek, masreszt publikacios teljesitmenyuket figyelembe veve milyen ismervek szerint csoportosithatok a kutatok? A publikacios teljesitmenyt jellemző het valtozo kozotti kapcsolatok vizsgalata soran – a 449 elemű adatallomany felhasznalasaval – hat elemzesre kerult sor. Az eredmenyek alapjan feny derul a kelet-kozepeuropai gazdasagtudomanyi kutatok kozlesi sajatossagaira (peldaul volumenorientaltsag, tarsszerzőseg preferalasa), tovabba a rangsorbeli poziciojukat befolyasolo publikacios teljesitmenyukre.

A tudomanyos eletpalya merfoldkoveinek elhelyezese az adott diszciplinahoz tartozo kozosseg korifeusainak felelőssege, munkajuk soran a meres legalabb annyira fontos, mint az eredmenyekről szolo diskurzus. A Statisztikai Szemle a kozelmultban nyitott szakmai parbeszedet a hazai gazdasagtudomanyi felsőoktatasban lebonyolitando habilitacios eljarasok publikacios kovetelmenyeinek meghatarozasarol. Ebben a folyamatban a hazai habilitaltak kozlemenyjegyzekenek matematikai-statisztikai modszerekkel tortenő feldolgozasa es a nemzetkozi felsőoktatasi gyakorlat osszehasonlitasa egyarant teret kapott. Jelen tanulmany a magyarorszagi gazdasagtudomanyi doktori iskolak vezetőinek habilitacioval kapcsolatos velemenyeből kiindulva veszi gorcső ala a szakpolitikai es jogszabalyi kornyezetet, valamint a kelet-kozep-europai regio versenytarsainak tudomanyos teljesitmenyet, es ezekre alapozva igyekszik a habilitacio intezmenyenek jovőjet meghatarozni.

A felsőoktatasi rendszerek es a felsőoktatasi intezmenyek ertekelesenek nemzetkozileg elismert modja a nemzetkozi egyetemminősitő rangsorok hasznalata. Ezek kozul az egyik legismertebb a QS-rangsor, ami hat indikator menten minősiti az intezmenyeket. Jelen tanulmanyunk ket celt fogalmazott meg. Előszor azt vizsgaljuk meg, hogy a QS-rangsor es a Scopus/SciVal-adatbazisbol nyerhető valtozokbol TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) rangsorolo eljarassal nyert egyetemi rangsorok hogyan viszonyulnak egymashoz. Az eredmeny nagy foku egyezest mutat. A masodik celunk az volt, hogy ezen a QS egyetemi listan szereplő magyar egyetemeket megvizsgaljuk a regi es uj rangsorok szerint. Egy egyetem kivetelevel a magyar egyetemek rangsora is nagy foku stabilitast mutatott. = The international university rankings are world-reputed modes to evaluate the higher education area and higher education institutions. The QS rankings is one the most popular among these, which evaluates institutions based on six indicators. This paper has two aims. First, we investigate how the QS rankings and alternative rankings based on data from SciVal correlate with each other. Our findings show a strong correlation. Our second goal was to examine the Hungarian higher education institutions on this QS university list according to the old and new rankings. With the exception of one university, the Hungarian institutions show high stability in these rankings.

In today's competitive and dynamic world, the importance of supplier evaluation has become more widely recognized. When considering measurement of supplier performance and supply impact the literature identifies two sets of criteria: management criteria and green criteria. Management criteria can be extended with process cost criteria, which then poses new requirements to be met by the evaluation methodologies. This paper aims to present a methodology that can handle the different characteristics of these criteria. As a solution, a green supplier selection problem is generalized.A Data Envelopment Analysis (DEA)-type supplier selection method was developed, where green factors served as the output variables of a DEA model, and management variables were the inputs. This new methodology examines, in addition to managerial and green criteria, the effect of inventory-related costs, such as the EOQ costs of inventory holding or ordering costs on the selected supplier. The parametrical linear programming of technological coefficients is used in the DEA method. This paper draws attention to a new problem, namely, the literature fails to provide solutions for how to handle the nonlinearity of the cost functions in the most commonly used methodologies.

Supplier selection is an important business decision. Beside traditional management criteria the environmental aspects are getting often recognition. In this paper the method of Data Envelopment Analysis (DEA) is used to study the extension of traditional supplier selection methods with environmental factors. The focus will be on the weight selection process which can control the selection. In this method we divide the criteria in two manners: the traditional and environmental (green) factors. Then with the help of DEA we are searching a weight system with which the environmental criteria can influence the decision with a representation of the green factors. To choose the mentioned weight system, we apply DEA (Data Envelopment Analysis) with common weights analysis (CWA) method. In this case of DEA/CWA the common weights are calculated with a linear programming problem.

The aim of this paper is to compare the development of the digital economy in Russia with that of the 28 countries of European Union (EU). Data were compiled from the European Commission’s International Digital Economy and Society Index (I-DESI 2018) database. After providing a brief overview of various alternative ways to measure the impact of information and communications technologies (ICT), we examine the most important features, advantages, and drawbacks of this database. We then describe the structure of our dataset and proceed with the analysis of the digital competitiveness of Russia and the EU-28. Our main research questions are concerned with the robustness of the EU data supply and the stability of its ranking. For this, we use the data envelopment analysis (DEA) method and the one-dimensional version of multidimensional scaling, which can also be employed for ranking issues. In addition to the conventional DEA method, we also investigate the viability of common-weights DEA models. We compare the results obtained to answer our questions. In evaluating the results, we also discern how data from Russia matches EU data on the digital economy. The comparison suggests that methods used in our study provide a similar solution, but the ranking of a few countries (including Russia) show wider variation.

A tudománymetria a kutatók, a tudományos intézmények és a tudományos kiadványok, mint folyóiratok és konferenciakötetek stb. teljesítményének mérése és annak módszertana. A Vezetéstudomány ez évi második tematikus száma a tudománymetria gazdaságtudományi oktatókra-kutatókra való alkalmazásának bemutatását tűzi zászlajára. A tematikus szám öt tanulmányt tartalmaz a gazdaságtudományok különböző területeiről, de kiemelten a gazdálkodástudományból.

The aim of this paper is to assess the digital development of the Russian Federation vis-a-vis the 28 countries of the European Union (EU-28), applying the DEA-type Composite Indicators (DEA/CI) and TOPSIS methods on a dataset comprising the five principal dimensions of the European Commission’s International Digital Economy and Society Index. The paper demonstrates how the DEA/CI and TOPSIS methods can be used to provide a framework for ranking the 29 countries in our dataset in the absence of explicit input criteria or predetermined weights that are required by the classical DEA method and the European Commission’s scoring model. According to these rankings, the Russian Federation demonstrates respectable results in digital economic and social development relative to Eastern and Southern member states of the European Union.

Jelen tanulmányban Oroszország digitális fejlődését hasonlítjuk össze az Európai Unió országaival a Nemzetközi digitális gazdaság és társadalom fejlettségét mérő mutató (I-DESI) öt fő dimenziója alapján. Kutatásunk célja a dimenziók közötti kapcsolatok és redundancia vizsgálata, a 29 vizsgált ország csoportosítása a többváltozós statisztikai elemzés eszközeivel, valamint Oroszország helyzetének részletesebb vizsgálata. Tanulmányunkban az I-DESI öt fő dimenziójából főkomponens-analízis segítségével (PCA) két látens dimenziót (faktort) emelünk ki, illetve a dimenziók közötti oksági kapcsolatokat is feltárjuk parciális korrelációs elemzés révén, amely megmutatja, hogy e dimenziók közül kettő a másik három dimenzió által megmagyarázható. Ezt követően klaszterelemzés segítségével csoportosítjuk a 29 országot, illetve többdimenziós skálázás (MDS) segítségével meghatározzuk az országok és országcsoportok helyzetét a két főkomponens által alkotott térben. Eredményeink alapján Oroszország a digitalizációt tekintve közepesen fejlett országnak tekinthető, de a földrajzi és gazdasági jellemzőit is tükröző egyedi jellegzetességeinek, sajátos fejlődési mintázatának köszönhetően egymagában önálló csoportot alkot a vizsgált országokon belül.

The theory of economic motion was Andras Brody’s main interest. This paper presents a simplifi ed framework of Brody’s economics. His multi-sector production and price theory is based on the Marxian theory of value reinterpreted by using measurement considerations. Economic motion in this framework is driven by technology represented by the internal proportions of production, not by external shocks. Prices and proportions jointly determine the economic structure and its motion (duality of prices and volumes). We derive the laws of motion of production and use of goods (consumption and accumulation) based on technological accounting balances. These laws determine a cyclical pattern. Using numerical examples we demonstrate how external changes in technology and valuations are propagated in changing the cyclical pattern of motion.

The role of the supplier and relationship management with the supply base in purchasing is increasingly appreciated. This highlights the importance of pre- and post-qualification data, and the need for the focus to shift from selection to rating and mapping opportunities for development in the process of relationship management. From a decision-theory perspective, this means that suppliers need to be informed about how specific performance indicators should be improved to increase their prospects of qualifying for selection. From the supply management point of view, it is important that the efficiency of suppliers is increased to the level at which criteria are met. We employ a DEA model to parameterize the related data, making it treatable using fuzzy or interval DEA models. The problems associated with missing and imprecise data in such models can also be solved using parametric linear programming. However, this approach means that technology coefficients are also parameterized, for which good analytical solutions are lacking. We therefore approach the problem using simulation.

Efficient order picking requires a coordinated way of combining and utilizing three kinds of heterogeneous resources: articles, devices, and operators. Usually, the assortment of articles is subject to permanent adaptations. Hence, the interdependent decisions of assigning articles to devices and allocating manpower among devices need to be adjusted and the problem has to be solved frequently for similar instances. We propose a combination of exact and heuristic solution approaches. For an immediate reaction to each assortment change, a heuristic approach applying metamodel-based optimization is used. The data required for estimating the metamodel is provided by an exact approach which is utilized from time to time to reset the system to an optimal state. Based on sampled data of a pharmaceutical wholesaler, we compare exact and heuristic approach with regard to quality and time of solving in-sample and out-of-sample instances.

A tanulmany arra a feltevesre epul, hogy minel erősebb a bizalomra meltosag szintje egy adott uzleti kapcsolatban, annal inkabb igaz, hogy nagy kockazatu tevekenysegek mennek vegbe benne. Ilyen esetekben a bizalomra meltosag a kapcsolatban zajlo esemenyek, cselekvesek iranyitasi eszkozeve valik, es az uzleti kapcsolatban megjelenik a cselekvesi hajlandosagkent ertelmezett bizalom. A tanulmany felhivja a figyelmet a bizalom es a bizalomra meltosag fogalmai kozotti kulonbsegre, szisztematikus kulonvalasztasuk fontossagara. Bemutatja az ugynevezett diadikus adatelemzes gazdalkodastudomanyi alkalmazasat. Empirikus eredmenyei is igazoljak, hogy ezzel a modszerrel az uzleti kapcsolatok tarsas jellemzőinek (koztuk a bizalomnak) es a kozottuk levő kapcsolatoknak melyebb elemzesere nyilik lehetőseg. ____ The paper rests on the behavioral interpretation of trust, making a clear distinction between trustworthiness (honesty) and trust interpreted as willingness to engage in risky situations with specific partners. The hypothesis tested is that in a business relation marked by high levels of trustworthiness as perceived by the opposite parties, willingness to be involved in risky situations is higher than it is in relations where actors do not believe their partners to be highly trustworthy. Testing this hypothesis clearly calls for dyadic operationalization, measurement, and analysis. The authors present the first economic application of a newly developed statistical technique called dyadic data analysis, which has already been applied in social psychology. It clearly overcomes the problem of single-ended research in business relations analysis and allows a deeper understanding of any dyadic phenomenon, including trust/trustworthiness as a governance mechanism.

This paper summarizes findings about papers involving supplier selection and evaluation using Data Envelopment Analysis (DEA) published between 2009 and 2018. It reviews how DEA , one of the most frequently used methods, supports the supplier selection and evaluation process and related management decisions. Its novelty stems from the fact that such a type of review has only been carried out in a much broader context, thus the present approach can reveal potentially new opportunities for development and application. A systematic literature review was completed involving 54 papers that propose the use of some form of DEA for supporting supplier-management-related decisions. The paper uses descriptive and multivariate statistics to cluster the reviewed papers. Although a large number of papers were published in the period under examination, most of them still focus on supplier selection. However, a limited number of papers were identified which are more practice oriented and support strategic decision making in supplier management. Papers considering sustainability tend to focus only on green factors, but in most cases it means an additional criterion in the evaluation. Sustainability problems do not generate substantially new DEA model versions.

Current order picking technologies are characterized by different degrees of automation. Irrespective of the automation level, order picking remains a labor-intensive process. Hence, the decisions on the deployment of installed technologies and on labor utilization are interdependent. We develop two planning approaches for an integrative decision support. In comparison to the simultaneous approach the sequential one induces coordination deficits, but less computational effort. In order to inquire into the behavior of both approaches, we conduct a numerical study using sampled data of a pharmaceutical wholesaler.

A szerzők egy altaluk kidolgozott ismetlődő bizalomjatekot mutatnak be es vizsgalnak empirikusan. A jatek megkulonbozteti a bizalom, a bizalomra meltosag es a megbizhatosag fogalmait. Mind a bizalom, mind a bizalomra meltosag a jatek soran a szereplők cselekveseiben mutatkozik meg, ezaltal ertelmezhető. A megbizhatosag ugyanakkor allomany jellegű fogalom, a bizalmat ado fel eszlelese, varakozasa arra vonatkozoan, mennyire lesz bizalomra melto a bizalmat kapo fel. A szerzők adatfelvetele az ismetelt bizalomjatekok csoportjaba tartozik. Egy jatek 10 korből allt. A jatek soran anonim parokat alakitottak ki, es kozvetlenul mertek a megbizhatosag eszlelt szintjeit. Jelentős kulonbseg a korabbi ismetelt bizalomjatekokhoz kepest, hogy a jatekkorokben a megoszthato osszeg kumulalodott. Mindez a valos uzleti kapcsolatokhoz hasonlito interaktiv szituaciot teremtett. Ezen kivul specialis kifizetőfuggvenyt (hasznossagfuggvenyt) alkalmaztak, melynek reven a jatekosok kozott egyuttműkodve versengő kapcsolat jott letre. A szerzők a bizalomjatek e specialis formajat hasznaltak arra, hogy teszteljek hipotezisuket, mely szerint a felek kozott kialakulo megbizhatosag a kapcsolatban zajlo esemenyek (bizalom es bizalomra meltosag) kovetkezmenyekent valtozik, alakul.

We study an integrated production–inventory system that manufactures new items of a certain product and receives some of the used items back. These can be either remanufactured on the same production line or disposed of. Used items awaiting remanufacturing need to be held in stock. New and as-good-as-new items are kept in stock, from which the product demand is satisfied. Controlling such a system involves decisions with regard to disposal of used items, succession of manufacturing and remanufacturing operations, and the choice of respective lot sizes. Recent works have referred to settings assuming variation in quality of returned items and a limited number of remanufacturing cycles that an item can undergo. We seek to determine optimal lot sizing for such a system and derive sufficient conditions for an optimal policy to forego remanufacturing.

Supplier assessment is widely studied in the literature as it is an important means of managing supplier relationships. Although some evaluation methods have been proposed in the literature to measure suppliers׳ green performance, they are not developed specifically to help other than strategic purchasing situation. Based on literature results our paper examines the extension of the vendor evaluation methods with environmental, green issues. This generalization means an extension of the traditional criteria and weight system of the supplier evaluation methods. In our paper the method composite indicators (CI) is used to study the extension of traditional supplier selection methods with environmental factors. The selection of the weight system can control the result of the selection process. Our goal is to choose such weights which affect the results of the selection process. In this method we divide the criteria in two manners: the traditional (managerial) and environmental (green) factors. Then with the help of CI we are searching a weight system with which the environmental criteria can influence the decision with a representation of the green factors. In our study we look for a weight system to determine the environmental factors, as an important decision factors. To choose the mentioned weight system, we apply data envelopment analysis (DEA) with the common weights analysis (CWA) method.

A kornyezeti hatasok rendszerint tulmutatnak egy vallalat hatarain, eppen ezert az ellatasi lanc kontextusban a kornyezeti szempontok ervenyesitese soran fontos szerep jut a beszerzesi donteseknek is. Szamos olyan peldat lehetne emliteni, amikor egy adott szempont szerint egy alternativa kornyezetileg előnyos, de az ellatasi lanc egeszet nezve mar kornyezetterhelő. A kornyezeti hatasok ellatasi lanc szinten valo merese azonban komoly kihivasokat jelent. Ezzel jelentős kutatasokat es fejleszteseket inspiralt a tema. Az egyik olyan terulet, amelyben komoly kutatasi eredmenyek szulettek, az a kornyezeti szempontok beszallitoi ertekelesbe valo beepitese. A kutatasok ezen iranyahoz csatlakozva a szerzők tanulmanyunkban azt keresik, hogyan lehet meghatarozni az egyik legaltalanosabban hasznalt szallitoertekelesi modszerben, a sulyozott pontrendszerben egy adott szemponthoz azt a sulyt, amely mellett az adott szempont mar dontesbefolyasolo tenyezőve valik. Ehhez a DEA (Data Envelopment Analysis) osszetett indikatorok (Composite Indicators, CI) modszeret alkalmazzak. A szempontok kozos sulyanak fontossaga megallapitasahoz a linearis programozas elmeletet hasznaljak. _____ Management decisions often have an environmental effect not just within the company, but outside as well, this is why supply chain context is highlighted in literature. Measuring environmental issues of supply decisions raise a lot of problems from methodological and practical point of view. This inspires a rapidly growing literature as a lot of studies were published focusing on how to incorporate environmental issues into supplier evaluation. This paper contributes to this stream of research as it develops a method to help weight selection. In the authors’ paper the method of Data Envelope Analysis (DEA) is used to study the extension of traditional supplier selection methods with environmental factors. The selection of the weight system can control the result of the selection process.

The paper focuses on the development of buyer – supplier relationships over time. Although there is an ongoing debate about the nature and characteristics of relationship life cycle, the existence of some kind of life cycle is usually assumed when timely development of these relationships is investigated. The objective of our analysis is to investigate this hidden hypothesis using quantitative research methodology. The research focusing on the development of business relationships over time has mainly used qualitative research methods and to the best of our knowledge, no one have yet attempted to measure any relevant variables and the pattern of their development over time using a quantitative methodology. In order to be able to test this hypothesis the level of relation-specific investments generated in the relationship, called the explicit investment measure, was chosen. We have conceptualized and measured it and tested empirically to what extent its development over time fits the pattern of the traditional mathematical model (representation) of the life cycle, which is usually described with a logistics curve. The development of this explicit investment measure over time is a dynamic phenomenon the analysis of which is not without methodological problem. We suggest and apply a procedure developed in the field of population dynamics that makes it possible to use cross sectional data for such dynamic analysis.

There is growing interest in identifying the drivers of and barriers to green purchasing, and many publications focus on motivational factors. However, the effects of these factors on the activities and means applied to sustainable purchasing are seldom investigated. This paper addresses this research gap and examines the impact of the motivational factors on green purchasing practices of the companies'. This paper also emphasises the role and motivational background of personal attitudes and reveals that there are differences among them. Based on the literature, a questionnaire was developed and a survey was completed in Hungary. The answers indicate that positive and compliant personal attitudes of purchasing managers' have different drivers and barriers, while differences are also present in sustainable purchasing practices. Purchasing managers with a positive personal attitude have better green purchasing practices but mainly concerning product performance level activities, which do not require in-depth green management information.