数据挖掘英文题目.doc

2.4. Suppose that the data for analysis includes the attribute age. The age values for the data tuples are (in increasing order) 13, 15, 16, 16, 19, 20, 20, 21, 22, 22, 25, 25, 25, 25, 30, 33, 33, 35, 35, 35, 35, 36, 40, 45, 46, 52, 70. (a) What is the mean of the data? What is the median? (b) What is the mode of the data? Comment on the datas modality (i.e., bimodal, trimodal, etc.). (c) What is the midrange of the data? (d) Can you ˉnd (roughly) the ˉrst quartile (Q1) and the third quartile (Q3) of the data? (e) Give the ˉve-number summary of the data. (f ) Show a boxplot of the data. (g) How is a quantile-quantile plot di?erent from a quantile plot ? 2.9. Suppose a hospital tested the age and body fat data for 18 randomly selected adults with the following result age 23 23 27 27 39 41 47 49 50 %fat 9.5 26.5 7.8 17.8 31.4 25.9 27.4 27.2 31.2 age 52 54 54 56 57 58 58 60 61 %fat 34.6 42.5 28.8 33.4 30.2 34.1 32.9 41.2 35.7 (a) Calculate the mean, median and standard deviation of age and %fat. (b) Draw the boxplots for age and %fat. (c) Draw a scatter plot and a q-q plot based on these two variables. (d) Normalize the two variables based on z-score normalization. (e) Calculate the correlation coe±cient (Persons product moment coe±cient). Are these two variables positively or negatively correlated? 2.11. Use the two methods below to normalize the following group of data: 200; 300; 400; 600; 1000 (a) min-max normalization by setting min = 0 and max = 1 (b) z-score normalization 4.4. Suppose that a base cuboid has three dimensions A; B; C, with the following number of cells: jAj = 1; 000; 000, jBj = 100, and jCj = 1000. Suppose that each dimension is evenly partitioned into 10 portions for chunking. (a) Assuming each dimension has only one level, draw the complete lattice of the cube. (b) If each cube cell stores one measure with 4 bytes, what is the total size of the computed cube if the cube is dense ? (c) State the order for computing the chunks in the cube that re