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Detecting and locating changes in highly multivariate data is a major concern in several current statistical applications. In this context, the first contribution of the paper is a novel non-parametric two-sample homogeneity test for multivariate data based on the well-known Wilcoxon rank statistic. The proposed two-sample homogeneity test statistic can be extended to deal with ordinal or censored data as well as to test for the homogeneity of more than two samples. The second contribution of the paper concerns the use of the proposed test statistic to perform retrospective change-point analysis. It is first shown that the approach is computationally feasible even when looking for a large number of change-points thanks to the use of dynamic programming. Computable asymptotic $p$-values for the test are then provided in the case where a single potential change-point is to be detected. Compared to available alternatives, the proposed approach appears to be very reliable and robust. This is particularly true in situations where the data is contaminated by outliers or corrupted by noise and where the potential changes only affect subsets of the coordinates of the data.

Anthropogenic activity such as damming or diversion of rivers cause extensive disturbance to ecosystems, as well as the interaction between surface water and groundwater. Following the diversion in 1992 of the River Danube (NW Hungary) and the construction of a water barrage system, the level of shallow groundwater dropped and altered the connection between surface water and groundwater. This paper outlines the changes in the interaction of surface water and shallow groundwater and other related environmental consequences caused by an 80% decrease in runoff resulting from this intervention. Time series (1996–2004) of 27 water quality variables measured from three surface- and three subsurface sampling sites were analyzed using periodicity-, hierarchical cluster- and principal component analyses. It was found that: (i) the degree of riverbed clogging increased due to diminished runoff; this clogging blocked the interaction between surface water and groundwater at certain sampling sites; (ii) extreme floods were capable of resetting this situation and changing the flow currents to differing degrees in the surface/groundwaters. These findings enabled a better understanding of the changes in water quality primarily attributable to the diversion of the river (the change in water level, riverbed clogging etc.). The changed hydrological setting of the subject area became very similar to that which might be expected to evolve due to climate change around the world. Thus, the study not only serves as an example for the processes evolving (e.g. riverbed clogging) in similarly modified river sections, but to those as well, which are expected to suffer from aridification.

This study investigated the attitudes toward statistics of graduate students who studied advanced statistics in a course in which the focus of instruction was the use of a computer program in class. The use of the program made it possible to provide an individualized, self-paced, student-centered, and activity-based course. The three sections involved in this study were offered in the 2001 spring term. There were complete data for 19 students, most of whom were white females. Fifteen were in advanced statistics, and four were in multivariate statistics. The instrument used was the Statistics Attitude Survey (D. Roberts and E. Bilderback, 1980). Both chi square and Kendall's Coefficient of Concordance indicated that there were differences in the distribution of ranks between the pre-test and post-test survey results. Most of these differences occurred as increases in the rankings marked at each end of the scales. That is, after the course, more students felt more strongly that they agreed or disagreed with statements about some aspects of statistics. Comments from the open-ended evaluation forms may help explain some of the other study findings. It is concluded that offering the course using computers may help improve students' attitudes about certain aspects of statistics. The course syllabus used in the study is appended. (Contains 14 references.) (Author/SLD)

This study investigated the attitudes toward statistics of graduate students who studied advanced statistics in a course in which the focus of instruction was the use of a computer program in class. The use of the program made it possible to provide an individualized, self-paced, student-centered, and activity-based course. The three sections involved in this study were offered in the 2001 spring term. There were complete data for 19 students, most of whom were white females. Fifteen were in advanced statistics, and four were in multivariate statistics. The instrument used was the Statistics Attitude Survey (D. Roberts and E. Bilderback, 1980). Both chi square and Kendall's Coefficient of Concordance indicated that there were differences in the distribution of ranks between the pre-test and post-test survey results. Most of these differences occurred as increases in the rankings marked at each end of the scales. That is, after the course, more students felt more strongly that they agreed or disagreed with statements about some aspects of statistics. Comments from the open-ended evaluation forms may help explain some of the other study findings. It is concluded that offering the course using computers may help improve students' attitudes about certain aspects of statistics. The course syllabus used in the study is appended. (Contains 14 references.) (Author/SLD)

This study investigated the attitudes toward statistics of graduate students who studied advanced statistics in a course in which the focus of instruction was the use of a computer program in class. The use of the program made it possible to provide an individualized, self-paced, student-centered, and activity-based course. The three sections involved in this study were offered in the 2001 spring term. There were complete data for 19 students, most of whom were white females. Fifteen were in advanced statistics, and four were in multivariate statistics. The instrument used was the Statistics Attitude Survey (D. Roberts and E. Bilderback, 1980). Both chi square and Kendall's Coefficient of Concordance indicated that there were differences in the distribution of ranks between the pre-test and post-test survey results. Most of these differences occurred as increases in the rankings marked at each end of the scales. That is, after the course, more students felt more strongly that they agreed or disagreed with statements about some aspects of statistics. Comments from the open-ended evaluation forms may help explain some of the other study findings. It is concluded that offering the course using computers may help improve students' attitudes about certain aspects of statistics. The course syllabus used in the study is appended. (Contains 14 references.) (Author/SLD)

This study investigated the attitudes toward statistics of graduate students who studied advanced statistics in a course in which the focus of instruction was the use of a computer program in class. The use of the program made it possible to provide an individualized, self-paced, student-centered, and activity-based course. The three sections involved in this study were offered in the 2001 spring term. There were complete data for 19 students, most of whom were white females. Fifteen were in advanced statistics, and four were in multivariate statistics. The instrument used was the Statistics Attitude Survey (D. Roberts and E. Bilderback, 1980). Both chi square and Kendall's Coefficient of Concordance indicated that there were differences in the distribution of ranks between the pre-test and post-test survey results. Most of these differences occurred as increases in the rankings marked at each end of the scales. That is, after the course, more students felt more strongly that they agreed or disagreed with statements about some aspects of statistics. Comments from the open-ended evaluation forms may help explain some of the other study findings. It is concluded that offering the course using computers may help improve students' attitudes about certain aspects of statistics. The course syllabus used in the study is appended. (Contains 14 references.) (Author/SLD)

This study investigated the attitudes toward statistics of graduate students who studied advanced statistics in a course in which the focus of instruction was the use of a computer program in class. The use of the program made it possible to provide an individualized, self-paced, student-centered, and activity-based course. The three sections involved in this study were offered in the 2001 spring term. There were complete data for 19 students, most of whom were white females. Fifteen were in advanced statistics, and four were in multivariate statistics. The instrument used was the Statistics Attitude Survey (D. Roberts and E. Bilderback, 1980). Both chi square and Kendall's Coefficient of Concordance indicated that there were differences in the distribution of ranks between the pre-test and post-test survey results. Most of these differences occurred as increases in the rankings marked at each end of the scales. That is, after the course, more students felt more strongly that they agreed or disagreed with statements about some aspects of statistics. Comments from the open-ended evaluation forms may help explain some of the other study findings. It is concluded that offering the course using computers may help improve students' attitudes about certain aspects of statistics. The course syllabus used in the study is appended. (Contains 14 references.) (Author/SLD)

The aim of our research was to choose the optimal mortar for the infantry battalion's mortar battery. The comparison was carried out using Analytic Hierarchy Process methodology (AHP) [1]. In our study we describe the application of Multi-Criteria Decision Analysis methods to select optimal military equipment, and we also show other mathematical models which could be useful to solve decision-making problems. During the process of solving this problem, the most important task was the calculation of weights that show the importance of various attributes. Since in this situation there are many decision makers (for example battalion commanders, battery commanders, infantry and artillery officers), we prepared an opinion survey. We asked 32 officers about the importance of attributes and we calculated 32 vectors based on 32 questionnaires. The result was 32 vectors, each of which described one officer s opinion. One of our goals was to calculate the differences among these opinions. In order to do this, we processed these vectors with Multi-Dimensional Scaling, Cluster Analysis and Box Plot Analysis.