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Politecnico di Milano Facoltà di Ingegneria dell’Informazione Data Mining and Text Mining Tecniche di Apprendimento Automatico Prof. Pier Luca Lanzi & Ing. Daniele Loiacono July 7, 2014 NAME MATRICOLA Solve the following problems and write the answer inside the problem box. Answers must be clearly written. Pencils are not allowed. The midterm consists of 3 sheets of paper. It must be returned with all the 3 sheets. No any other sheet can be added. No sheet can be removed. This is a closed-book, closed-notes exam. Only non-programmable calculators are allowed. Notes/books/mobile phones are not allowed. If you are caught using forbidden material, the exam will immediately end and an RP grade will be recorded; then, your Data Mining exam will consist of an oral examination from then on. All the answers must be adequately motivated. Grades The image cannot be displayed. Your computer may not have enough memory to open the image, or the image may have been corrupted. Restart your computer, and then open the file again. If the red x still appears, you may have to delete the image and then insert it again. Problem 1. Apply hierarchical clustering using single linkage and Euclidean distance to the following dataset where x and y represents the two attributes. x y 1 2"7"2 10"3"3 1"7"4 5"8"5 10"1"6 3"5"7 3"6"8 2"2"9 4"9"10 6"9" In particular, plot the dendrogram and suggest a possible clustering given the result. Answer should be properly motivated. Problem 1. (continued) Problem 2. Explain what are boxplots. Discuss the difference between barplots, histograms and boxplots. When do they should be employed? Problem 3. You are attending a presentation where your colleagues are showing the result of an exhaustive cluster analysis they performed using k-means. As the main results,…