5. Distribution of Redundant Link % on web pages (N =1861) Std. Dev = 37.33 Mean = 22.1 N = 1861.00 Median = 14 3 480.0 440.0 400.0 360.0 320.0 280.0 240.0 200.0 160.0 120.0 80.0 40.0 0.0 1000 800 600 400 200 0
6. Plotting a histogram: endpoint convention, plot frequencies, make equal intervals etc.
11. Distribution of word count (N=1903) Std. Dev = 725.24 Mean = 393.2 Maximum = 20,357 Minimum = 0 Median = 223 20000.0 18000.0 16000.0 14000.0 12000.0 10000.0 8000.0 6000.0 4000.0 2000.0 0.0 1600 1400 1200 1000 800 600 400 200 0
12. Distribution of word count (N=1897) top six removed Std. Dev = 474.04 Mean = 368.0 Maximum = 4132 Minimum = 0 Median = 223 7 4000.0 3600.0 3200.0 2800.0 2400.0 2000.0 1600.0 1200.0 800.0 400.0 0.0 800 600 400 200 0
13. Distribution of word count (N=1873) Std. Dev = 360.30 Mean = 333.4 Maximum = 4132 Minimum = 0 WORDCNT2 Median = 220 2400.0 2200.0 2000.0 1800.0 1600.0 1400.0 1200.0 1000.0 800.0 600.0 400.0 200.0 0.0 500 400 300 200 100 0
31. Distribution of judges ratings for the Webby Awards Std. Dev = 1.98 Mean = 6.3 N = 1867.00 Skewness = -.43 Kurtosis = -.201 Median = 6.3 12 10.0 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 500 400 300 200 100 0
32. It is a remarkable fact that many histograms in real life tend to follow the Normal Curve. For such histograms, the mean and SD are good summary statistics . The average pins down the center, while the SD gives the spread. For histogram which do not follow the normal Curve, the mean and SD are not good summary statistics. What when the histogram is not normal ...
33. +- 3 SD = (384 * 3) = 1152 Mean - 1152 = about 30% sample had negative number of links Mean = 348.3 Std. Dev = 384.83 Distribution of word count on web pages 13 2800.0 2600.0 2400.0 2200.0 2000.0 1800.0 1600.0 1400.0 1200.0 1000.0 800.0 600.0 400.0 200.0 0.0 500 400 300 200 100 0
34. Note. A percentile is a score below which a certain % of sample is When SD is influenced by outliers Use inter quartile range 75th percentile - 25th percentile
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37. Positively Skewed and Leptokurtic: Word Count Std. Dev = 725.24 Mean = 393.2 N = 1903.00 Kurtosis = 321.84 Skewness = 13.62 Median = 223 20000.0 18000.0 16000.0 14000.0 12000.0 10000.0 8000.0 6000.0 4000.0 2000.0 0.0 1600 1400 1200 1000 800 600 400 200 0
38. Distribution of word count (N=1897) top six removed Std. Dev = 474.04 Mean = 368.0 N = 1897.00 Skewness = 3.49 Kurtosis = 16.40 Median = 223 4000.0 3600.0 3200.0 2800.0 2400.0 2000.0 1600.0 1200.0 800.0 400.0 0.0 800 600 400 200 0