947 resultados para method comparison


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A distance-based inconsistency indicator, defined by the third author for the consistency-driven pairwise comparisons method, is extended to the incomplete case. The corresponding optimization problem is transformed into an equivalent linear programming problem. The results can be applied in the process of filling in the matrix as the decision maker gets automatic feedback. As soon as a serious error occurs among the matrix elements, even due to a misprint, a significant increase in the inconsistency index is reported. The high inconsistency may be alarmed not only at the end of the process of filling in the matrix but also during the completion process. Numerical examples are also provided.

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Pairwise comparison is a popular assessment method either for deriving criteria-weights or for evaluating alternatives according to a given criterion. In real-world applications consistency of the comparisons rarely happens: intransitivity can occur. The aim of the paper is to discuss the relationship between the consistency of the decision maker—described with the error-free property—and the consistency of the pairwise comparison matrix (PCM). The concept of error-free matrix is used to demonstrate that consistency of the PCM is not a sufficient condition of the error-free property of the decision maker. Informed and uninformed decision makers are defined. In the first stage of an assessment method a consistent or near-consistent matrix should be achieved: detecting, measuring and improving consistency are part of any procedure with both types of decision makers. In the second stage additional information are needed to reveal the decision maker’s real preferences. Interactive questioning procedures are recommended to reach that goal.

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An important variant of a key problem for multi-attribute decision making is considered. We study the extension of the pairwise comparison matrix to the case when only partial information is available: for some pairs no comparison is given. It is natural to define the inconsistency of a partially filled matrix as the inconsistency of its best, completely filled completion. We study here the uniqueness problem of the best completion for two weighting methods, the Eigen-vector Method and the Logarithmic Least Squares Method. In both settings we obtain the same simple graph theoretic characterization of the uniqueness. The optimal completion will be unique if and only if the graph associated with the partially defined matrix is connected. Some numerical experiences are discussed at the end of the paper.

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A cikk a páros összehasonlításokon alapuló pontozási eljárásokat tárgyalja axiomatikus megközelítésben. A szakirodalomban számos értékelő függvényt javasoltak erre a célra, néhány karakterizációs eredmény is ismert. Ennek ellenére a megfelelő módszer kiválasztása nem egy-szerű feladat, a különböző tulajdonságok bevezetése elsősorban ebben nyújthat segítséget. Itt az összehasonlított objektumok teljesítményén érvényesülő monotonitást tárgyaljuk az önkonzisztencia és önkonzisztens monotonitás axiómákból kiindulva. Bemutatásra kerülnek lehetséges gyengítéseik és kiterjesztéseik, illetve egy, az irreleváns összehasonlításoktól való függetlenséggel kapcsolatos lehetetlenségi tétel is. A tulajdonságok teljesülését három eljárásra, a klasszikus pontszám eljárásra, az ezt továbbfejlesztő általánosított sorösszegre és a legkisebb négyzetek módszerére vizsgáljuk meg, melyek mindegyike egy lineáris egyenletrendszer megoldásaként számítható. A kapott eredmények új szempontokkal gazdagítják a pontozási eljárás megválasztásának kérdését. _____ The paper provides an axiomatic analysis of some scoring procedures based on paired comparisons. Several methods have been proposed for these generalized tournaments, some of them have been also characterized by a set of properties. The choice of an appropriate method is supported by a discussion of their theoretical properties. In the paper we focus on the connections of self-consistency and self-consistent-monotonicity, two axioms based on the comparisons of object's performance. The contradiction of self-consistency and independence of irrel-evant matches is revealed, as well as some possible reductions and extensions of these properties. Their satisfiability is examined through three scoring procedures, the score, generalised row sum and least squares methods, each of them is calculated as a solution of a system of linear equations. Our results contribute to the problem of finding a proper paired comparison based scoring method.

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Az egyes nemzetek számviteli szabályozásának vizsgálatánál az adott ország sajátosságaiból eredően részben eltérő szabályozások alakultak ki. Az induktív megközelítésű vizsgálatok jellemzően a szabályozási kérdések széles körét fogják át, de csak néhány tényező mentén közelítve. A cash flow-kimutatások témakörénél a legtöbbször csak azt nézték, hogy van-e előírás a kimutatás elkészítésére, de a részletekkel már kevésbé foglalkoztak. Ebből adódóan e területen viszonylag kis különbséget mutattak ki ezek a felmérések. A szerző kutatása szerint a nemzeti cash flow-kimutatások szabályozásának részleteiben eltérések tapasztalhatók, és ezek alapján a nemzetek klaszterelemzéssel hierarchikusan csoportokba rendezhetők. _____ Research has found that as a result of their particularities, different countries have established partly different accounting frameworks. Studies with inductive approaches typically encompass a wide range of regulatory issues, but based on a limited number of factors only. In the case of Statements of Cash Flows, most studies have so far only examined the existence of rules governing the presentation of the statement, without an in-depth analysis of the details. Therefore, these studies only found relatively minor differences in this field. The author’s research shows that many differences exist in the details of national Cash Flow Statement regulations, which makes it possible to classify the countries in groups using the method of hierarchical clustering.

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OBJECTIVE: The aim of this meta-analysis was to compare the efficacy and safety of infliximab-biosimilar and other available biologicals for the treatment of rheumatoid arthritis (RA), namely abatacept, adalimumab, certolizumab pegol, etanercept, golimumab, infliximab, rituximab and tocilizumab. METHODS: A systematic literature review of MEDLINE database until August 2013 was carried out to identify relevant randomized controlled trials (RCTs). Bayesian mixed treatment comparison method was applied for the pairwise comparison of treatments. Improvement rates by the American College of Rheumatology criteria (ACR20 and ACR50) at week 24 were used as efficacy endpoints, and the occurrence of serious adverse events was considered to assess the safety of the biologicals. RESULTS: Thirty-six RCTs were included in the meta-analysis. All the biological agents proved to be superior to placebo. For ACR20 response, certolizumab pegol showed the highest odds ratio (OR) compared to placebo, OR 7.69 [95 % CI 3.69-14.26], followed by abatacept OR 3.7 [95 % CI 2.17-6.06], tocilizumab OR 3.69 [95 % CI 1.87-6.62] and infliximab-biosimilar OR 3.47 [95 % CI 0.85-9.7]. For ACR50 response, certolizumab pegol showed the highest OR compared to placebo OR 8.46 [3.74-16.82], followed by tocilizumab OR 5.57 [95 % CI 2.77-10.09], and infliximab-biosimilar OR 4.06 [95 % CI 1.01-11.54]. Regarding the occurrence of serious adverse events, the results show no statistically significant difference between infliximab-biosimilar and placebo, OR 1.87 [95 % CI 0.74-3.84]. No significant difference regarding efficacy and safety was found between infliximab-biosimilar and the other biological treatments. CONCLUSION: This is the first indirect meta-analysis in RA that compares the efficacy and safety of biosimilar-infliximab to the other biologicals indicated in RA. We found no significant difference between infliximab-biosimilar and other biological agents in terms of clinical efficacy and safety.

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A special class of preferences, given by a directed acyclic graph, is considered. They are represented by incomplete pairwise comparison matrices as only partial information is available: for some pairs no comparison is given in the graph. A weighting method satisfies the property linear order preservation if it always results in a ranking such that an alternative directly preferred to another does not have a lower rank. We study whether two procedures, the Eigenvector Method and the Logarithmic Least Squares Method meet this axiom. Both weighting methods break linear order preservation, moreover, the ranking according to the Eigenvector Method depends on the incomplete pairwise comparison representation chosen.

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The Accounting Information System (AIS) is an important course in the Department of Accounting (DoAc) of universities in Taiwan. This course is required for seniors not only because it meets the needs of the profession, but also because it provides continual study for the department's students.^ The scores of The National College and University Joint Entrance Examination (NUEE) show that students with high learning ability are admitted to public universities with high scores, while those with low learning ability are admitted only to private universities. The same situation has been found by the researcher while teaching an AIS course in DoAc of The Public Chun Shin University (CSU) and The Private Chinese Culture University (CCU).^ The purpose of this study was to determine whether low ability students enrolled in private universities in Taiwan in a mastery learning program could attain the same level as high ability students from public universities enrolled in a traditional program. An experimental design was used. The mastery learning method was used to teach three groups of seniors with low learning ability studying in the DoAc at CCU. The traditional method was used to teach the control group which consisted of senior students of DoAc of CSU with high learning ability. As a part of the mastery learning strategy, a formative test, quizzes, and homework were completed by the experimental group only, while the mid-term examination was completed by both groups as part of the course. The dependent variable was the summative test, the final examination. It was completed by both groups upon the course's completion.^ As predicted, there were significant differences between the two groups' results on the pretest. There were no significant differences between the two groups' results on the posttest. These findings support the hypothesis of the study and reveal the effectiveness of mastery learning strategies with low learning ability students. ^

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The purpose of this research was to compare the delivery methods as practiced by higher education faculty teaching distance courses with recommended or emerging standard instructional delivery methods for distance education. Previous research shows that traditional-type instructional strategies have been used in distance education and that there has been no training to distance teach. Secondary data, however, appear to suggest emerging practices which could be pooled toward the development of standards. This is a qualitative study based on the constant comparative analysis approach of grounded theory.^ Participants (N = 5) of this study were full-time faculty teaching distance education courses. The observation method used was unobtrusive content analysis of videotaped instruction. Triangulation of data was accomplished through one-on-one in-depth interviews and from literature review. Due to the addition of non-media content being analyzed, a special time-sampling technique was designed by the researcher--influenced by content analyst theories of media-related data--to sample portions of the videotape instruction that were observed and counted. A standardized interview guide was used to collect data from in-depth interviews. Coding was done based on categories drawn from review of literature, and from Cranton and Weston's (1989) typology of instructional strategies. The data were observed, counted, tabulated, analyzed, and interpreted solely by the researcher. It should be noted however, that systematic and rigorous data collection and analysis led to credible data.^ The findings of this study supported the proposition that there are no standard instructional practices for distance teaching. Further, the findings revealed that of the emerging practices suggested by proponents and by faculty who teach distance education courses, few were practiced even minimally. A noted example was the use of lecture and questioning. Questioning, as a teaching tool was used a great deal, with students at the originating site but not with distance students. Lectures were given, but were mostly conducted in traditional fashion--long in duration and with no interactive component.^ It can be concluded from the findings that while there are no standard practices for instructional delivery for distance education, there appears to be sufficient information from secondary and empirical data to initiate some standard instructional practices. Therefore, grounded in this research data is the theory that the way to arrive at some instructional delivery standards for televised distance education is a pooling of the tacitly agreed-upon emerging practices by proponents and practicing instructors. Implicit in this theory is a need for experimental research so that these emerging practices can be tested, tried, and proven, ultimately resulting in formal standards for instructional delivery in television education. ^

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Reversed-phase high performance liquid chromatographic methods for the analysis of Haloacetic acids have been developed and compared to conventional direct detection methods. Haloacetic acids commonly found in drinking water, including monochloro-, dichloro-, bromo-, iodo- and trichloroacetic acids- have been studied. The ion pairing agent benzyltributylammonium ion was studied in detail using indirect UV and indirect fluorescence detection. Five different competing ions were evaluated to decrease analysis times and lower the detection limit by this new method. The direct detection method utilized an ammonium sulfate buffer and UV detection yielding a detection limit of 100 ppb. The indirect method developed has the advantage of being able to simultaneously analyze UV and non-UV absorbing ions and molecules but requires long equilibration times and demonstrated lower sensitivity than the direct method. ^

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Current views of the nature of knowledge and of learning suggest that instructional approaches in science education pay closer attention to how students learn rather than on teaching. This study examined the use of approaches to teaching science based on two contrasting perspectives in learning, social constructivist and traditional, and the effects they have on students' attitudes and achievement. Four categories of attitudes were measured using the Upper Secondary Attitude Questionnaire: Attitude towards school, towards the importance of science, towards science as a career, and towards science as a subject in school. Achievement was measured by average class grades and also with a researcher/teacher constructed 30-item test that involved three sub-scales of items based on knowledge, and applications involving near-transfer and far-transfer of concepts. The sample consisted of 202 students in nine intact classrooms in chemistry at a large high school in Miami, Florida, and involved two teachers. Results were analyzed using a two-way analysis of covariance (ANCOVA) with a pretest in attitude as the covariate for attitudes and prior achievement as the covariate for achievement. A comparison of the adjusted mean scores was made between the two groups and between females and males. ^ With constructivist-based teaching, students showed more favorable attitude towards science as a subject, obtained significantly higher scores in class achievement, total achievement and achievement on the knowledge sub-scale of the knowledge and application test. Students in the traditional group showed more favorable attitude towards school. Females showed significantly more positive attitude towards the importance of science and obtained significantly higher scores in class achievement. No significant interaction effects were obtained for method of instruction by gender. ^ This study lends some support to the view that constructivist-based approaches to teaching science is a viable alternative to traditional modes of teaching. It is suggested that in science education, more consideration be given to those aspects of classroom teaching that foster closer coordination between social influences and individual learning. ^

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There is growing popularity in the use of composite indices and rankings for cross-organizational benchmarking. However, little attention has been paid to alternative methods and procedures for the computation of these indices and how the use of such methods may impact the resulting indices and rankings. This dissertation developed an approach for assessing composite indices and rankings based on the integration of a number of methods for aggregation, data transformation and attribute weighting involved in their computation. The integrated model developed is based on the simulation of composite indices using methods and procedures proposed in the area of multi-criteria decision making (MCDM) and knowledge discovery in databases (KDD). The approach developed in this dissertation was automated through an IT artifact that was designed, developed and evaluated based on the framework and guidelines of the design science paradigm of information systems research. This artifact dynamically generates multiple versions of indices and rankings by considering different methodological scenarios according to user specified parameters. The computerized implementation was done in Visual Basic for Excel 2007. Using different performance measures, the artifact produces a number of excel outputs for the comparison and assessment of the indices and rankings. In order to evaluate the efficacy of the artifact and its underlying approach, a full empirical analysis was conducted using the World Bank's Doing Business database for the year 2010, which includes ten sub-indices (each corresponding to different areas of the business environment and regulation) for 183 countries. The output results, which were obtained using 115 methodological scenarios for the assessment of this index and its ten sub-indices, indicated that the variability of the component indicators considered in each case influenced the sensitivity of the rankings to the methodological choices. Overall, the results of our multi-method assessment were consistent with the World Bank rankings except in cases where the indices involved cost indicators measured in per capita income which yielded more sensitive results. Low income level countries exhibited more sensitivity in their rankings and less agreement between the benchmark rankings and our multi-method based rankings than higher income country groups.

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This research sought to understand the role that differentially assessed lands (lands in the United States given tax breaks in return for their guarantee to remain in agriculture) play in influencing urban growth. Our method was to calibrate the SLEUTH urban growth model under two different conditions. The first used an excluded layer that ignored such lands, effectively rendering them available for development. The second treated those lands as totally excluded from development. Our hypothesis was that excluding those lands would yield better metrics of fit with past data. Our results validate our hypothesis since two different metrics that evaluate goodness of fit both yielded higher values when differentially assessed lands are treated as excluded. This suggests that, at least in our study area, differential assessment, which protects farm and ranch lands for tenuous periods of time, has indeed allowed farmland to resist urban development. Including differentially assessed lands also yielded very different calibrated coefficients of growth as the model tried to account for the same growth patterns over two very different excluded areas. Excluded layer design can greatly affect model behavior. Since differentially assessed lands are quite common through the United States and are often ignored in urban growth modeling, the findings of this research can assist other urban growth modelers in designing excluded layers that result in more accurate model calibration and thus forecasting.

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Belowground biomass is a critical factor regulating ecosystem functions of coastal marshes, including soil organic matter (SOM) accumulation and the ability of these systems to keep pace with sea-level rise. Nevertheless, belowground biomass responses to environmental and vegetation changes have been given little emphasis marsh studies. Here we present a method using stable carbon isotopes and color to identify root and rhizomes of Schoenoplectus americanus (Pers.) Volk. ex Schinz and R. Keller (C3) and Spartina patens (Ait.) Muhl. (C4) occurring in C3− and C4-dominated communities in a Chesapeake Bay brackish marsh. The functional significance of the biomass classes we identified is underscored by differences in their chemistry, depth profiles, and variation in biomass and profiles relative to abiotic and biotic factors. C3 rhizomes had the lowest concentrations of cellulose (29.19%) and lignin (14.43%) and the lowest C:N (46.97) and lignin:N (0.16) ratios. We distinguished two types of C3 roots, and of these, the dark red C3 roots had anomalously high C:N (195.35) and lignin:N (1.14) ratios, compared with other root and rhizome classes examined here and with previously published values. The C4-dominated community had significantly greater belowground biomass (4119.1 g m−2) than the C3-dominated community (3256.9 g m−2), due to greater total root biomass and a 3.6-fold higher C3-root:rhizome ratio in the C4-dominated community. C3 rhizomes were distributed significantly shallower in the C4-dominated community, while C3 roots were significantly deeper. Variability in C3 rhizome depth distributions was explained primarily by C4 biomass, and C3 roots were explained primarily by water table height. Our results suggest that belowground biomass in this system is sensitive to slight variations in water table height (across an 8 cm range), and that the reduced overlap between C3 and C4 root profiles in the C4-dominated community may account for the greater total root biomass observed in that community. Given that future elevated atmospheric CO2 and accelerated sea-level rise are likely to increase C3 abundance in Atlantic and Gulf coast marshes, investigations that quantify how patterns of C3 and C4 belowground biomass respond to environmental and biological factors stand to improve our understanding of ecosystem-wide impacts of global changes on coastal wetlands.

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Relationships between academic achievement and type of curriculum delivery system, Montessori or traditional, in a diverse group of learners from a public school district were examined in this study. In a repeated measures, within subjects design, students from an elementary Montessori program were paired with agemates from a traditional group on the basis of similar Stanford Achievement Test Scores in reading or math during the baseline year. Two subsequent administrations of the Stanford were observed for each subject to elucidate possible differences which might emerge based on program affiliation over the three year duration of the study. ^ Mathematics scores for both groups were not observed to be significantly different, although following the initial observation, the Montessori group continued to produce higher mean scores than did the traditional students. Marginal significance between the groups suggests that the data analysis should continue in an effort to elucidate a possible trend toward significance at the .05 level. ^ Reading scores for the groups demonstrated marginally significant differences by one analytical method, and significant differences when analyzed with a second method. In the second and third years of the study, Montessori students produced means which consistently outperformed the traditional group. ^ Recommendations included tracking subsequent administrations of the Stanford Achievement Test for all pairs of subjects in order to evaluate emerging trends in both subject areas. ^