a   b   sum         count mean
cat pan 42.32715826 89    0.47558605
cat hat 43.18440957 90    0.47982677
cat dog 39.24147285 78    0.50309581
cat wye 45.19677452 77    0.58697110
cat cat 37.89414848 79    0.47967277
pan wye 40.13529971 78    0.51455512
pan pan 36.22633427 77    0.47047187
pan hat 35.11586926 67    0.52411745
pan dog 37.81756019 73    0.51804877
pan cat 42.23567663 89    0.47455816
wye cat 40.80572298 74    0.55142869
wye hat 41.16669670 87    0.47318042
wye dog 40.61954682 76    0.53446772
wye wye 32.49097274 67    0.48493989
wye pan 33.02719552 66    0.50041205
dog hat 43.51516221 88    0.49449048
dog pan 45.61401108 87    0.52429898
dog dog 43.54595570 87    0.50052823
dog wye 37.22379467 79    0.47118727
dog cat 45.64259510 83    0.54991078
hat hat 48.05889742 88    0.54612383
hat wye 34.05426962 70    0.48648957
hat pan 42.53875750 85    0.50045597
hat cat 44.32565470 88    0.50370062
hat dog 37.11424443 78    0.47582365
