Let S be a set of n points in the plane. We present data structures that solve range-aggregate query problems on three geometric extent measure problems. Using these data structures, we can report, for any axis-parallel query rectangle Q, the area/perimeter of the convex hull, the width, and the radius of the smallest enclosing disk of the points in S ∩Q.

Does campaign duration affect election outcomes? To date, this question has largely evaded political scientists, but it is reasonable to expect systematic links between campaign length and candidate performance in elections. We hypothesize that longer campaigns would help challengers' electoral fortunes, thereby curbing incumbency advantage and potentially boosting competitiveness in elections....

Actually the growing volume of data provided by different sources some times may present inconsistencies, the data could be incomplete with lack of values or containing aggregate data, noisy containing errors or outliers, etc. Then data cleaning consist in filling missing values, smooth noisy data, identify or remove outliers and resolve inconsistencies. In more general definition, data cleanin...

Decision makers have become accustomed to making decisions using summarized or aggregate data through the use of financial and accounting reports. The use of aggregate data minimizes the effects of information overload on a decision maker; however it may not provide a decision maker all the details he or she would like to have. The effects of aggregated versus detailed information presentation ...

Density-based clusterization techniques are investigated as a basis for constructing histograms in multi-dimensional scenarios, where traditional techniques fail in providing effective data synopses. The main idea is that locating dense and sparse regions can be exploited to partition the data into homogeneous buckets, preventing dense and sparse regions from being summarized into the same aggr...