Shedding Light on the Doing Business Index: a Machine Learning Approach

Background: The World Bank (WB) acknowledged the importance of business regulatory environment and therefore created a metric which ranks 190 countries based on their level of business regulation for domestic firms measured by the Doing Business Index (DBI). Objectives: The question which attracted our attention is whether all the observed entities should be given the same weighting scheme. Methods/Approach: The approach we propose as an answer is two-fold. First, we cluster the countries covered by the DBI. In the next step, we apply the statistical multivariate Composite I-distance Indicator (CIDI) methodology to determine new, data-driven weights for each of the retained clusters. Results: The obtained results show that there is a difference between the weighting schemes proposed by the CIDI methodology. Conclusions: One can argue that one weighting scheme does not fit all the observed countries, meaning that additional analyses on the DBI are suggested to explore its stability and its weighting scheme

Multivariate approach to imposing additional constraints on the Benefit-of-the-Doubt model: The case of QS World University Rankings by Subject

Composite indexes have become a valuable asset for stakeholders as they provide ranks of entities and information upon which decisions are made. However, certain questions about their development procedure have been raised recently, especially regarding the weighting process. To tackle the observed issue, in this paper we propose a new multivariate approach for defining weights. Namely, the model based on the Data Envelopment Analysis (DEA), the Benefit-of-the-Doubt (BoD) model, has been used with significant success in the process of composite index development. On the other hand, the Composite I-distance Indicator (CIDI) methodology stands out as an impartial method for assigning weights to indicators. By combining these two approaches, some of the limitations of the original BoD model could be overcome. As a result, new entity-specific weights which maximize the value of the composite index can be proposed. As a case study, we analysed the Quacquarelli Symonds (QS) World University Rankings by Subject in the field of statistics and operational research. The obtained results, which are based on the data-driven weights, can provide new insights into the nature of the observed ranking. The approach presented here might provoke further research on the topic of composite index weights and on the university rankings by subject

Time trend and clinical pattern of extrapulmonary tuberculosis in Serbia, 1993-2007

Background/Aim. Increased incidence of extrapulmonary tuberculosis (XPTB) is reported worldwide. Serbia is a country in socio-economic transition period with lowmiddle HIV prevalence and intermediate-to-low tuberculosis (TB) incidence rate, 100% directly observed treatment (DOT) coverage, and mandatory BCG vaccination at birth. The aim of the study was to examine the incidence trend and clinical features of XPTB in Serbia during a 15-year period. Methods. This retrospective observational study included XPTB cases diagnosed in the period between 1st January 1993 and 31st Decembre 2007, according to the reports of the National Referral Institute of Lung Diseases and Tuberculosis in Belgrade and Central Tuberculosis Register. Population estimates with extrapolations were based on 1991 and 2002 census data. Results. While the overall TB incidence rate showed a slight, not significant decreasing trend (p = 0.535), a significant increase was found for XPTB (y = 1.7996 + 0.089x; R2 = 0.4141; p = 0.01). A total of 2,858 XPTB cases (newly diagnosed and 10% relapses) gave an average age specific incidence rate of 2.51/100,000 population (95% confidence interval, SD = 0.6182) with 8.9% annual increase. The male-to-female ratio was 0.54. Lymph nodes were most frequently affected site (48.5%) followed by genitourinary (20.5%), pleural (12%), and osseo-arthicular (10.3%) TB. Treatment outcome was successful in 88.29% of patients (cured and completed), 3.64% died, 5.18% interrupted, 0.57% displaced, and 2.3% unknown. Conclusion. Increasing trend of XPTB incidence rate may be a result of increased morbidity due to still present risk factors, possible higher detection rate in Serbia and better notification. A high coverage of newborns with BCG vaccination at birth might contribute to a decreased number and rare XPTB cases in children

Molekularna identifikacija i karakterizacija dvojedarnih Rhizoctonia spp. prouzrokovača crne truleži korena jagode u Srbiji

Strawberry production is a popular, fast-growing agricultural business in Serbia. Its cultivar selection has been changing fast, following market demands. One of the limiting factors of strawberry production worldwide is black root rot, primarily caused by binucleate Rhizoctonia. Recently, outbreaks of black root rot of strawberry have occurred in Serbia and the estimated disease incidence was up to 30%. Isolates of binucleate Rhizoctonia AG-A were recovered from symptomatic strawberry plants, and characterized on the bases of morphological, molecular and pathogenic features. Despite their uniform morphological characteristics, the isolates demonstrated genetic variability within ITS rDNA, grouping into three different phylogenetic sub-clusters which comprise AG-A isolates originating from Italy, Israel, Japan and the USA. The binucleate Rhizoctonia AG-A from Serbia exhibited uniform virulence on strawberry after inoculation of daughter plants and detached leaf petioles, as well as on seedlings of bean, carrot and sunflower, while they were non-pathogenic to wheat, maize, tomato, pepper, tobacco, cucumber, lettuce, peas, cabbage, rapeseed and sugar beet.Proizvodnja jagode je popularna grana poljoprivrede u Srbiji koja se brzo razvija. Sastav sorti uključenih u proizvodnju podleže stalnim promenama u skladu sa zahtevima tržišta. Jedan od ograničavajućih faktora u proizvodnji jagode širom sveta je crna trulež korena, bolest koju najčešće izazivaju dvojedarne vrste roda Rhizoctonia. U Srbiji je poslednjih godina nekoliko puta zabeležena pojava crne truleži jagode uz učestalost koja je iznosila do 30%. Iz biljaka jagode sa simptomima izdvojeni su izolati dvojedarne Rhizoctonia AG-A i okarakterisani na osnovu morfološih i molekularnih osobina i patogenosti. Uprkos uniformnim morfološkim osobinama, izolati su ispoljili genetičku varijabilnost na osnovu sekvence ITS rDNK, grupišući se u tri različita filogentska sub-klastera koji su obuhvatali isolate iz Italije, Izraela, Japana i SAD. Izolati dvojedarnih Rhizoctonia AG-A poreklom iz Srbije ispoljili su uniformnu virulentnost na jagodi nakon inokulacija živića i fragmenata lisnih peteljki, kao i na sejancima pasulja, mrkve i suncokreta, dok nisu bili patogeni za pšenicu, kukuruz, paradajz, papriku, duvan, krastavac, salatu, grašak, kupus i šećernu repu

STATISTIČKI PRISTUP MERENJU EFIKASNOSTI BANAKA

Evaluating efficiency of banks has always represented a challenge for researchers. Although many different methods have been proposed, no particular approach is agreed upon. In this paper, statistical I–distance method is proposed. We employed this method on the Serbian banks in the five-year period. Results obtained by I-distance methodology are presented and thoroughly elaborated.Evaluacija efikasnosti banaka je oduvek predstavljala izazov za istraživače.Iako su predložene brojne metode, ne postoji opšteprihvaćeni pristup rešavanju dotičnog problema. U našem radu je predložena metoda I - odstojanja koja je primenjena na evaluaciju banaka u Srbiji tokom petogodišnjeg perioda. Dobijeni rezultati su prezentovani i detaljno objašnjeni

Diverzitet i patogenost različitih hemotipova Fusarium graminearum kompleksa poreklom sa zrna ječma

Vrste u okviru Fusarium graminearum kompleksa (Fg) su jedne od najvažnijih patogena strnih žita i kukuruza. Kompleks Fg sadrži najmanje 15 filogenetski različitih vrsta. Ove vrste prouzrokuju bolest poznatu kao fusarioza klasa pšenice, ječma i pirinča, kao i trulež klipa kukuruza. Pored toga što dovodi do gubitka prinosa, zaraženo zrno je lošijeg kvaliteta, uključujući kontaminaciju mikotoksinima od kojih su najznačajniji nivalenol (NIV), deoksinivalenol (DON) i njegove acetilovane forme (3ADON i 15ADON). U ovom istraživanju, ispitivana je patogenost izolata, pripadnost određenom hemotipu kao i potencijal za sintezu mikotoksina kod 22 izolata Fusarium graminearum sakupljenih sa zrna ječma na 12 lokaliteta u Srbiji. Određivanje hemotipa kao i potencijal sinteze mikotoksina urađen je pomoću tečne hromatografije sa tandem masenom spektrofotometrijom (HPLC/LC-MS). Proces prečišćavanja uzoraka je izvršen u koloni MycoSep 113 Trich i MycoSep 230 Niv (Romer Labs, USA). Kao mobilna faza korišćena je voda-acetonitril (90:10 v/v) za 3ADON i 15ADON. Komponente su razdvojene na Acclaim Polar Advantage II, C18 (150 × 4.6 mm, 3 μm) koloni na temperaturi od 25 oC. Patogenost ispitivanih izolata testirana je in vitro (u laboartoriji) na listu ječma. Veštačka inokulacija lista ječma obavljena je po metodi koju su opisali Imathiu i sar. (2009). Od 22 ispitivana izolata, dva izolata su pripadala 3ADON hemotipu, dok su svi ostali pripadali 15ADON hemotipu. Izolati sa 3ADON hemotipom su sintetisali niske koncentarcije ukupnog deoksinivalenola (4,12-11,09 µg/g), dok su izolati sa 15ADON hemotipom sintetisali veće koncentracije 8,74-102,32 µg/g. Rezultati u ovom radu su pokazali da između patogenosti izolata i sinteze mikotoksina u in vitro testu nije utvrđena značajna pozitivna korelacija (r = 0,32)

Molecular identification and characterization of binucleate Rhizoctonia spp. associated with black root rot of strawberry in Serbia

Strawberry production is a popular, fast-growing agricultural business in Serbia. Its cultivar selection has been changing fast, following market demands. One of the limiting factors of strawberry production worldwide is black root rot, primarily caused by binucleate Rhizoctonia. Recently, outbreaks of black root rot of strawberry have occurred in Serbia and the estimated disease incidence was up to 30%. Isolates of binucleate Rhizoctonia AG-A were recovered from symptomatic strawberry plants, and characterized on the bases of morphological, molecular and pathogenic features. Despite their uniform morphological characteristics, the isolates demonstrated genetic variability within ITS rDNA, grouping into three different phylogenetic sub-clusters which comprise AG-A isolates originating from Italy, Israel, Japan and the USA. The binucleate Rhizoctonia AG-A from Serbia exhibited uniform virulence on strawberry after inoculation of daughter plants and detached leaf petioles, as well as on seedlings of bean, carrot and sunflower, while they were non-pathogenic to wheat, maize, tomato, pepper, tobacco, cucumber, lettuce, peas, cabbage, rapeseed and sugar beet

Residential Building Stock in Serbia: Classification and Vulnerability for Seismic Risk Studies

Regional seismic risk assessment is necessary for designing effective seismic risk mitigation measures. In general, such risk assessment studies consist of three components: hazard, vulnerability, and exposure modelling. This paper lays the foundations for regional seismic risk assessment of the residential building stock in Serbia and addresses each of the three seismic risk assessment components, either by reviewing the existing or proposing novel models. First, a review of seismic hazard models and seismic design codes used in Serbia in the past 70 years was presented. Next, an overview of Serbia’s population metrics and historical development of Serbian’s residential building stock was presented to provide the context for the exposure model. Furthermore, the paper proposed a novel building classification for Serbia's residential building stock, which is based on the existing building taxonomies, but it has been adapted to account for the local building characteristics. Building damage patterns reported in past earthquakes in Serbia and neighbouring countries were reviewed as a basis for damage classification pertaining to building typologies included in the proposed classification. Finally, the results of a preliminary vulnerability model were presented in the form of expert-based fragility functions derived for buildings typical of Serbia's residential building stock

The effects of whey and pumpkin seed oil on blood biochemical parameters of liver function and lipid profile in rats chronically drinking low concentrations of ethanol

We studied the effects of whey and pumpkin seed oil supplementation on the biochemical parameters in blood serum of male rats after chronic ad libitum alcohol consumption. The levels of AST, ALT, total bilirubin, ALP, LDH, triglycerides, total cholesterol, HDL, LDL, VLDL, triglyceride/HDL ratio, total cholesterol/HDL ratio (cholesterol ratio) and LDL/HDL ratio (index of atherosclerosis) were determined in rats after six weeks of treatment with: (i) ethanol (12% ethanol, ad libitum), (ii) whey (2 g/kg per day), (iii) pumpkin seed oil (2 mL/kg per day), (iv) both ethanol and whey, and (v) both ethanol and pumpkin seed oil. The results showed no changes in the levels of AST, ALT, total bilirubin, ALP, total cholesterol, HDL and VLDL in alcoholic rats when compared to the controls (fed with a standard laboratory diet ad libitum) and rats supplemented with whey and pumpkin seed oil. Our results suggest that alcohol consumption in small doses for 6 weeks changes lipid metabolism and significantly elevates the LDL/HDL ratio (index of atherosclerosis) but does not induce extensive liver damage. Ethanol consumption in our experimental conditions lowered the triglyceride level as well as the triglyceride/HDL ratio, suggesting lipid redistribution and the induction of some cardio-protective effect. However, ethanol induced a higher index of atherosclerosis. Pumpkin seed oil showed some protective potential in alcoholic rats by lowering the total cholesterol/HDL ratio, but it elevated the LDH. Whey consumption prevented elevation of the atherosclerosis index, pointing to its protective role, probably through the redistribution of lipids. However, whey in combination with ethanol elevated LDH

DOI:10.2298/YUJOR0902323M RANKING OF BANKS IN SERBIA 1

Abstract: It is often very difficult to rank entities characterized by more than one indicator. In the case of banking sector, especially in transition countries, it would be important to determine the relationship among the banks, regarding their efficiency and relevant characteristics. The results obtained in two different ranking processes are presented, discussed and compared in this paper. The first procedure is based on Data Envelopment Analysis, mathematical programming technique that can be applied to assessing the efficiency of a variety of entities, using variety of data. The second procedure is based on I-distance, a multivariate statistical method for ranking entities. Both methods allow the use of several criteria, and they both give one single index which can be considered as a rank. The complementary use of the two methods provides more realistic picture of the tendencies in the banking sector and the combination of the results obtained in two processes provides a useful background for more comprehensive evaluation of the banks efficiency