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Table 7 Sensitivity and positive predictive value (PPV) of the flexible and cylindrical space-time scan statistics.

From: A flexibly shaped space-time scan statistic for disease outbreak detection and monitoring

    zip codes population
   traditional power sensitivity (%) PPV (%) sensitivity (%) PPV (%)
Cluster A; s* = 1; high risk
Day 31 flexible (K = 20)      
  cylindrical (K = 20) 0.860 85.30 89.45 85.30 91.50
  cylindrical (50% pop) 0.862 85.90 88.79 85.90 90.84
Day 32 flexible (K = 20) 0.988 98.80 84.50 98.80 87.80
  cylindrical (K = 20) 0.996 99.50 97.44 99.50 98.18
  cylindrical (50% pop) 0.996 99.50 97.33 99.50 98.08
Day 33 flexible (K = 20) 0.999 99.90 96.27 99.90 97.32
  cylindrical (K = 20) 0.999 99.90 99.48 99.90 99.65
  cylindrical (50% pop) 0.999 99.90 99.48 99.90 99.65
Cluster A5; s* = 5; high risk
Day 31 flexible (K = 20) 0.797 66.08 55.93 67.29 63.00
  cylindrical (K = 20) 0.850 69.62 80.35 71.65 84.21
  cylindrical (50% pop) 0.847 70.62 78.17 71.62 82.02
Day 32 flexible (K = 20) 0.994 92.22 70.17 92.94 76.73
  cylindrical (K = 20) 0.996 88.78 85.14 90.86 89.41
  cylindrical (50% pop) 0.996 88.96 84.81 91.05 89.11
Day 33 flexible (K = 20) 1.000 95.88 80.02 96.64 85.25
  cylindrical (K = 20) 1.000 91.42 87.32 93.66 91.67
  cylindrical (50% pop) 1.000 91.42 87.30 93.66 91.65
The Rockaways; s* = 5; high risk
Day 31 flexible (K = 20) 0.769 60.68 72.09 69.04 73.58
  cylindrical (K = 20) 0.855 62.32 91.63 74.45 91.76
  cylindrical (50% pop) 0.840 61.40 91.04 73.65 91.15
Day 32 flexible (K = 20) 0.992 86.76 87.36 94.17 89.86
  cylindrical (K = 20) 0.997 77.00 96.84 92.75 97.46
  cylindrical (50% pop) 0.997 77.00 96.84 92.75 97.46
Day 33 flexible (K = 20) 1.000 92.16 93.81 97.15 95.97
  cylindrical (K = 20) 1.000 78.50 98.06 94.51 98.59
  cylindrical (50% pop) 1.000 78.50 98.06 94.51 98.59
Hudson River, s* = 20; high risk
Day 31 flexible (K = 20) 0.656 20.07 64.99 26.00 69.72
  cylindrical (K = 20) 0.597 14.23 61.10 18.16 65.18
  cylindrical (50% pop) 0.632 26.15 50.70 31.26 53.71
Day 32 flexible (K = 20) 0.964 32.17 73.59 41.81 78.36
  cylindrical (K = 20) 0.933 24.13 61.55 31.58 66.69
  cylindrical (50% pop) 0.949 42.90 50.27 51.50 53.96
Day 33 flexible (K = 20) 0.998 34.91 79.39 46.27 84.17
  cylindrical (K = 20) 0.994 27.23 60.56 36.75 66.20
  cylindrical (50% pop) 0.995 48.14 47.34 58.54 51.34