1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/rlm/jen.clj	Thu Jul 19 10:56:39 2012 -0500
     1.3 @@ -0,0 +1,136 @@
     1.4 +(ns rlm.jen)
     1.5 +
     1.6 +(defn select-cells [n total-groups]
     1.7 +  (map (fn [_] (int (* total-groups (Math/random)))) (range n)))
     1.8 +
     1.9 +(defn all-selected? [selections n] 
    1.10 +  (= n (count (set selections))))
    1.11 +
    1.12 +(defn probability-of-all-selected
    1.13 +  [n desired total-groups total-trials]
    1.14 +  (let [trials
    1.15 +        (map (fn [_]
    1.16 +               (all-selected?
    1.17 +                (select-cells n total-groups) desired))
    1.18 +             (range total-trials))
    1.19 +        prob
    1.20 +        (/ (count (filter identity trials)) total-trials)]
    1.21 +    prob))
    1.22 +
    1.23 +(defn your-problem [up-to trials-per-test]
    1.24 +  (print "selections       probability of getting all 15\n")
    1.25 +  (dorun
    1.26 +   (map
    1.27 +    (fn [n]
    1.28 +      (let [prob
    1.29 +            (probability-of-all-selected
    1.30 +             n 15 15 trials-per-test)]
    1.31 +        (printf "%10d             %1.3f\n" n (float prob))))
    1.32 +    (range up-to))))
    1.33 +
    1.34 +
    1.35 +;; rlm.jen> (your-problem 100 1000)
    1.36 +;; selections       probability of getting all 15
    1.37 +;;          0             0.000
    1.38 +;;          1             0.000
    1.39 +;;          2             0.000
    1.40 +;;          3             0.000
    1.41 +;;          4             0.000
    1.42 +;;          5             0.000
    1.43 +;;          6             0.000
    1.44 +;;          7             0.000
    1.45 +;;          8             0.000
    1.46 +;;          9             0.000
    1.47 +;;         10             0.000
    1.48 +;;         11             0.000
    1.49 +;;         12             0.000
    1.50 +;;         13             0.000
    1.51 +;;         14             0.000
    1.52 +;;         15             0.000
    1.53 +;;         16             0.000
    1.54 +;;         17             0.000
    1.55 +;;         18             0.001
    1.56 +;;         19             0.000
    1.57 +;;         20             0.001
    1.58 +;;         21             0.004
    1.59 +;;         22             0.005
    1.60 +;;         23             0.012
    1.61 +;;         24             0.008
    1.62 +;;         25             0.028
    1.63 +;;         26             0.031
    1.64 +;;         27             0.049
    1.65 +;;         28             0.045
    1.66 +;;         29             0.056
    1.67 +;;         30             0.100
    1.68 +;;         31             0.113
    1.69 +;;         32             0.125
    1.70 +;;         33             0.159
    1.71 +;;         34             0.152
    1.72 +;;         35             0.203
    1.73 +;;         36             0.216
    1.74 +;;         37             0.259
    1.75 +;;         38             0.285
    1.76 +;;         39             0.283
    1.77 +;;         40             0.331
    1.78 +;;         41             0.371
    1.79 +;;         42             0.420
    1.80 +;;         43             0.421
    1.81 +;;         44             0.456
    1.82 +;;         45             0.491
    1.83 +;;         46             0.527
    1.84 +;;         47             0.558
    1.85 +;;         48             0.534
    1.86 +;;         49             0.568
    1.87 +;;         50             0.580
    1.88 +;;         51             0.605
    1.89 +;;         52             0.668
    1.90 +;;         53             0.676
    1.91 +;;         54             0.678
    1.92 +;;         55             0.706
    1.93 +;;         56             0.726
    1.94 +;;         57             0.732
    1.95 +;;         58             0.743
    1.96 +;;         59             0.755
    1.97 +;;         60             0.761
    1.98 +;;         61             0.789
    1.99 +;;         62             0.804
   1.100 +;;         63             0.798
   1.101 +;;         64             0.837
   1.102 +;;         65             0.825
   1.103 +;;         66             0.832
   1.104 +;;         67             0.865
   1.105 +;;         68             0.871
   1.106 +;;         69             0.880
   1.107 +;;         70             0.894
   1.108 +;;         71             0.892
   1.109 +;;         72             0.892
   1.110 +;;         73             0.903
   1.111 +;;         74             0.911
   1.112 +;;         75             0.917
   1.113 +;;         76             0.926
   1.114 +;;         77             0.937
   1.115 +;;         78             0.922
   1.116 +;;         79             0.942
   1.117 +;;         80             0.927
   1.118 +;;         81             0.936
   1.119 +;;         82             0.952
   1.120 +;;         83             0.952
   1.121 +;;         84             0.960
   1.122 +;;         85             0.973
   1.123 +;;         86             0.969
   1.124 +;;         87             0.952
   1.125 +;;         88             0.963
   1.126 +;;         89             0.973
   1.127 +;;         90             0.971
   1.128 +;;         91             0.969
   1.129 +;;         92             0.980
   1.130 +;;         93             0.968
   1.131 +;;         94             0.975
   1.132 +;;         95             0.991
   1.133 +;;         96             0.980
   1.134 +;;         97             0.977
   1.135 +;;         98             0.982
   1.136 +;;         99             0.988
   1.137 +;; nil
   1.138 +          
   1.139 +