The data below are 500 observations from a standard bivariate normal distribution (Z1, Z2), and the same data rounded to the nearest 0.5 (Z1R, Z2R).

 
        Z1           Z2     Z1R     Z2R
   -0.83923     -0.09391      -1       0
   -0.49464     -0.95089    -0.5      -1
   -0.23595     -0.39965       0    -0.5
    0.44705     -1.17349     0.5      -1
   -0.42167      1.31421    -0.5     1.5
    1.35469      1.33031     1.5     1.5
   -0.62061     -1.56261    -0.5    -1.5
   -0.25408      0.71974    -0.5     0.5
   -0.53801      0.50476    -0.5     0.5
   -1.21637      0.96843      -1       1
    0.27365     -0.58286     0.5    -0.5
    1.21251      0.15664       1       0
     1.0331      0.02917       1       0
   -0.14748      0.19471       0       0
   -0.30431     -1.28012    -0.5    -1.5
    0.24683      0.14572       0       0
   -0.65829     -1.05372    -0.5      -1
   -0.38053      -1.3501    -0.5    -1.5
    0.66269      0.21829     0.5       0
    0.67571     -0.80152     0.5      -1
    0.21062     -1.68536       0    -1.5
    0.08577      0.55528       0     0.5
   -0.40738     -0.04883    -0.5       0
    0.05143     -0.89931       0      -1
    1.06118      1.32107       1     1.5
   -0.74758      0.67432    -0.5     0.5
   -1.43717     -1.61477    -1.5    -1.5
   -1.25231     -0.02815    -1.5       0
   -0.09067      1.04517       0       1
    0.25039     -0.91148     0.5      -1
     0.6613      0.77343     0.5       1
    1.22803       0.1126       1       0
    1.12469     -0.47307       1    -0.5
    0.19475      -0.2899       0    -0.5
    0.67512     -1.11578     0.5      -1
   -0.89685     -1.87138      -1      -2
    -1.5172      0.86293    -1.5       1
   -0.47494     -0.39197    -0.5    -0.5
   -0.87316      0.67685      -1     0.5
   -1.42553     -0.13581    -1.5       0
   -0.39805     -0.42751    -0.5    -0.5
    0.97245     -0.05927       1       0
   -0.95444       1.2667      -1     1.5
    0.13609     -1.22926       0      -1
   -0.85676     -0.86458      -1      -1
   -0.24265       0.1439       0       0
     0.4381     -0.48867     0.5    -0.5
   -1.39096     -0.61511    -1.5    -0.5
    0.18045       0.5587       0     0.5
    1.37408     -0.30767     1.5    -0.5
    0.22186      0.72419       0     0.5
   -2.21333      1.28144      -2     1.5
   -0.13833      0.62542       0     0.5
   -0.11853     -1.31327       0    -1.5
    0.14929       -0.138       0       0
   -0.46957     -1.36145    -0.5    -1.5
   -0.30374      1.56878    -0.5     1.5
   -1.29146     -0.66162    -1.5    -0.5
   -0.10251      0.63672       0     0.5
   -0.90341     -1.08297      -1      -1
    0.58873     -1.61482     0.5    -1.5
   -1.04155     -1.12544      -1      -1
   -1.17249       0.1294      -1       0
    -0.8139     -2.09742      -1      -2
    1.03093     -0.08652       1       0
     0.3756       2.3464     0.5     2.5
   -0.05537     -0.61873       0    -0.5
     0.9783      0.53942       1     0.5
    0.07291     -1.48337       0    -1.5
   -0.54651      0.27084    -0.5     0.5
    1.73751      2.26311     1.5     2.5
    1.03986     -0.21985       1       0
   -0.09603      0.39158       0     0.5
    0.13643      0.01285       0       0
   -0.34409     -0.20007    -0.5       0
   -1.26187     -0.90585    -1.5      -1
   -1.01914      0.80593      -1       1
    1.88194      1.36659       2     1.5
       0.11     -1.72717       0    -1.5
    0.96494      0.20392       1       0
   -0.12175      0.16771       0       0
   -0.72243      -2.3137    -0.5    -2.5
    -0.1085      2.69752       0     2.5
    0.52722     -0.45825     0.5    -0.5
    0.05286      1.17939       0       1
     0.7241      0.34782     0.5     0.5
    0.05068      -0.2645       0    -0.5
   -0.57489      0.23818    -0.5       0
   -1.23839      2.85807      -1       3
    0.87664      0.60539       1     0.5
   -0.84369      1.93802      -1       2
   -0.66355      0.05992    -0.5       0
    0.92944     -0.15336       1       0
    0.93231     -0.53445       1    -0.5
   -0.04084      1.47253       0     1.5
   -0.67612      0.26422    -0.5     0.5
    0.05593      0.78841       0       1
    0.79551     -0.16634       1       0
    1.07065      2.48446       1     2.5
   -1.16379     -0.55549      -1    -0.5
    1.84448     -0.02896       2       0
   -2.18686     -0.76049      -2      -1
    0.52335     -1.44898     0.5    -1.5
   -0.55954     -1.69263    -0.5    -1.5
    1.44006     -0.00894     1.5       0
    1.68497     -0.42991     1.5    -0.5
    0.57403     -1.43375     0.5    -1.5
    0.09486      1.23333       0       1
    1.28009     -0.28609     1.5    -0.5
    0.21224      0.64307       0     0.5
   -0.03078      0.54087       0     0.5
   -0.03684      0.03606       0       0
   -0.20487      0.50097       0     0.5
    2.03516       -1.047       2      -1
    0.29331     -0.37429     0.5    -0.5
     0.4749     -0.93028     0.5      -1
    0.79727      0.38099       1     0.5
    0.72747      -0.3235     0.5    -0.5
   -0.38941       -1.481    -0.5    -1.5
    -0.4705      0.01902    -0.5       0
   -1.26544      0.32978    -1.5     0.5
    0.79352     -1.75012       1      -2
    0.82211      1.53733       1     1.5
   -1.97999      -1.2086      -2      -1
   -0.34535      1.06208    -0.5       1
    0.19895      0.18177       0       0
   -0.59027      0.47999    -0.5     0.5
    1.30063      0.76941     1.5       1
   -0.49645      0.01614    -0.5       0
   -1.58716     -1.01374    -1.5      -1
   -1.93846     -0.30585      -2    -0.5
    0.28291     -0.54277     0.5    -0.5
   -1.76362     -2.91363      -2      -3
    -0.6076     -0.83189    -0.5      -1
    1.36177      0.35216     1.5     0.5
   -0.86324      0.24513      -1       0
    1.43334      0.65636     1.5     0.5
    0.16174      0.11187       0       0
   -1.08357      0.14578      -1       0
    1.00601      0.39705       1     0.5
    0.40758       0.1921     0.5       0
    -0.3509      2.39253    -0.5     2.5
   -0.45712      0.21539    -0.5       0
    0.51714      1.99743     0.5       2
   -1.52599     -0.20017    -1.5       0
    0.27263      0.78923     0.5       1
   -0.72043     -1.45046    -0.5    -1.5
    0.16691     -1.61404       0    -1.5
    0.34877     -0.76969     0.5      -1
    0.62209       1.2616     0.5     1.5
    1.14888     -0.28222       1    -0.5
   -0.24222      1.19026       0       1
    0.15555     -0.29243       0    -0.5
   -0.07651      0.70799       0     0.5
   -0.25234       0.0246    -0.5       0
    -0.8252     -1.27742      -1    -1.5
   -0.49577      0.62342    -0.5     0.5
    0.22238      0.01564       0       0
   -0.55647     -1.15517    -0.5      -1
    0.26963     -0.02483     0.5       0
   -1.42648       1.0688    -1.5       1
     -0.327      1.36039    -0.5     1.5
   -1.08762      0.36972      -1     0.5
    0.73543      0.97459     0.5       1
   -1.40554      0.10215    -1.5       0
   -0.57707     -0.52993    -0.5    -0.5
    0.07803      -0.2251       0       0
    0.46341      0.45946     0.5     0.5
   -1.14903     -0.78162      -1      -1
    1.19073     -1.53621       1    -1.5
   -0.23702      0.53257       0     0.5
   -0.64456     -1.61081    -0.5    -1.5
     0.0938     -2.09564       0      -2
    0.35282      0.67811     0.5     0.5
    0.14282      1.47449       0     1.5
   -0.45862      1.00169    -0.5       1
   -0.74588      0.12307    -0.5       0
   -0.85469     -0.26391      -1    -0.5
   -1.31295     -1.53767    -1.5    -1.5
    0.01298      0.08927       0       0
   -1.09878     -0.30831      -1    -0.5
   -1.29807      1.65062    -1.5     1.5
    0.55373      0.25348     0.5     0.5
    0.18626      0.49346       0     0.5
   -1.38172      0.56953    -1.5     0.5
   -0.48629      -1.1132    -0.5      -1
   -0.86531     -0.08554      -1       0
   -0.02449     -0.76973       0      -1
    0.08408      0.66393       0     0.5
    0.30049      0.24879     0.5       0
   -1.25116     -0.53349    -1.5    -0.5
   -0.21718     -0.11345       0       0
    0.27523      0.63025     0.5     0.5
    0.35504      0.95636     0.5       1
   -0.02258     -0.26877       0    -0.5
    0.40322      1.47887     0.5     1.5
     1.3534     -0.57817     1.5    -0.5
   -0.72446     -0.08481    -0.5       0
   -0.15096      0.10538       0       0
   -1.57548     -0.64715    -1.5    -0.5
    2.00104      1.50434       2     1.5
   -1.04345      0.77693      -1       1
   -0.33871     -0.56161    -0.5    -0.5
    1.44942     -0.78595     1.5      -1
   -0.30356      1.03383    -0.5       1
    0.01883      0.89863       0       1
    -1.6691     -0.56662    -1.5    -0.5
   -0.22177     -0.21425       0       0
   -0.51618     -2.27183    -0.5    -2.5
      0.374      1.00806     0.5       1
   -0.07299      0.02687       0       0
    0.56669     -1.35082     0.5    -1.5
   -0.49301     -1.65673    -0.5    -1.5
    0.59224     -1.30601     0.5    -1.5
    0.77803     -2.06616       1      -2
    0.88635     -0.03595       1       0
    -0.9174      0.77231      -1       1
   -2.62362     -2.10632    -2.5      -2
   -0.17428       1.0995       0       1
    0.53098     -0.46645     0.5    -0.5
   -0.94324      0.45252      -1     0.5
    -0.4827     -1.69258    -0.5    -1.5
    0.55596     -2.77229     0.5      -3
    2.44118     -1.05486     2.5      -1
   -0.44261     -0.21645    -0.5       0
   -0.06786     -0.30839       0    -0.5
   -0.28461      0.27105    -0.5     0.5
   -0.48295      0.33199    -0.5     0.5
   -0.63247     -1.71857    -0.5    -1.5
     1.2382      0.03357       1       0
   -0.60499     -0.03977    -0.5       0
   -0.13669      0.76919       0       1
   -1.07371      1.25907      -1     1.5
    0.17415      0.46011       0     0.5
   -0.91289      0.06301      -1       0
   -0.98523       0.3233      -1     0.5
    1.37251     -2.02153     1.5      -2
     1.0587      1.20236       1       1
    1.33604     -0.40126     1.5    -0.5
    1.56775       1.1402     1.5       1
   -1.00689     -0.52358      -1    -0.5
   -0.69846      0.42705    -0.5     0.5
    0.75232     -0.48049       1    -0.5
    0.98731      0.80917       1       1
   -0.54487      0.68481    -0.5     0.5
    2.42775     -1.07753     2.5      -1
   -0.79568      2.34162      -1     2.5
   -0.21408      0.82038       0       1
    1.73189      0.49944     1.5     0.5
   -0.97531     -0.15255      -1       0
    0.09933     -0.35326       0    -0.5
   -1.63868      0.83319    -1.5       1
    0.09231     -0.93534       0      -1
    2.02096     -0.21261       2       0
   -0.66843     -0.53735    -0.5    -0.5
   -1.29457      0.17651    -1.5       0
    0.36675      0.14074     0.5       0
    0.60132     -0.36157     0.5    -0.5
    0.36942     -0.83107     0.5      -1
    1.65642      1.36686     1.5     1.5
   -1.43419       0.9038    -1.5       1
   -1.32502      0.08426    -1.5       0
     0.9966     -2.77243       1      -3
   -1.23901      1.55453      -1     1.5
   -0.55563      0.05355    -0.5       0
    1.10341      1.33308       1     1.5
    -0.1095     -1.48798       0    -1.5
    1.78356      0.42122       2     0.5
    -1.5692     -1.81232    -1.5      -2
    0.26939     -1.00433     0.5      -1
   -0.72661       1.7504    -0.5       2
    0.59848     -0.00141     0.5       0
     0.8614      0.83071       1       1
   -0.58098     -0.31779    -0.5    -0.5
    1.55127      0.17456     1.5       0
      0.704      0.10165     0.5       0
    0.91973     -0.15606       1       0
    0.32473      1.04472     0.5       1
      0.324     -1.94339     0.5      -2
   -1.16547     -1.70802      -1    -1.5
    0.68656     -0.71633     0.5    -0.5
   -0.48955      1.78405    -0.5       2
    0.26155      1.90968     0.5       2
   -1.03941      0.70633      -1     0.5
    0.56967      -1.3517     0.5    -1.5
   -0.84587     -1.81205      -1      -2
    1.02339     -1.26772       1    -1.5
    1.37746     -1.45659     1.5    -1.5
    0.81853      0.36666       1     0.5
   -1.55103      0.63584    -1.5     0.5
   -0.72666     -0.73557    -0.5    -0.5
   -1.65144      1.67792    -1.5     1.5
    0.34706     -1.15054     0.5      -1
    0.25586      1.44317     0.5     1.5
    0.17897      0.11481       0       0
    0.31091     -0.52782     0.5    -0.5
      2.018      0.99973       2       1
    0.61671      1.39871     0.5     1.5
   -1.02286     -0.29839      -1    -0.5
    -1.3529      0.53331    -1.5     0.5
    0.17739      1.72446       0     1.5
    0.79353      0.33198       1     0.5
   -0.25011      0.97193    -0.5       1
    0.34829     -1.39581     0.5    -1.5
   -0.70871     -0.10874    -0.5       0
    1.90621     -0.06681       2       0
    0.06176     -1.15397       0      -1
   -0.79579     -1.31625      -1    -1.5
    1.64081      0.27916     1.5     0.5
    0.09179      0.38898       0     0.5
   -1.88559      0.07052      -2       0
    0.23353      0.59404       0     0.5
   -0.45008       0.5662    -0.5     0.5
    0.11973     -0.74598       0    -0.5
    1.70526     -1.53801     1.5    -1.5
   -0.56856      0.84917    -0.5       1
   -0.03196     -1.25203       0    -1.5
     0.7281     -2.67556     0.5    -2.5
   -0.12495      1.43233       0     1.5
    0.55407      1.39083     0.5     1.5
    0.02032      0.00048       0       0
   -1.35446     -1.19419    -1.5      -1
   -1.70206      1.82669    -1.5       2
   -0.98194      0.55519      -1     0.5
    1.69498      0.92862     1.5       1
   -1.46957      0.42241    -1.5     0.5
   -1.10591      0.08208      -1       0
    0.72891      0.56398     0.5     0.5
   -1.94145      1.43857      -2     1.5
    1.51427      -0.1166     1.5       0
    1.51246     -0.19083     1.5       0
    1.20592      0.51918       1     0.5
   -1.11051      0.52753      -1     0.5
    0.37874     -0.97686     0.5      -1
    0.68075     -1.51167     0.5    -1.5
   -0.11659     -0.54346       0    -0.5
    1.07632     -1.42893       1    -1.5
     2.8306     -0.31956       3    -0.5
    1.35135      0.08376     1.5       0
    2.06294     -0.64638       2    -0.5
    -1.0355     -0.17861      -1       0
    1.02651     -1.21504       1      -1
    0.32574     -1.15734     0.5      -1
    -1.0877      1.49014      -1     1.5
    0.43139      0.23931     0.5       0
   -0.25985       1.6997    -0.5     1.5
    0.63304     -1.28454     0.5    -1.5
    3.05221     -0.89812       3      -1
    0.78454     -1.24542       1      -1
    1.01676      1.82532       1       2
    0.42322      0.63288     0.5     0.5
    0.75769     -0.93924       1      -1
    0.54907     -0.49096     0.5    -0.5
   -1.86653      1.03292      -2       1
   -0.78443     -1.30161      -1    -1.5
    0.65158     -0.65392     0.5    -0.5
   -0.03752      0.26295       0     0.5
   -1.44412      0.12359    -1.5       0
    1.34638     -0.12993     1.5       0
    0.32049      -0.5246     0.5    -0.5
    1.31605     -2.53583     1.5    -2.5
    0.34207      0.74992     0.5     0.5
    0.15116      -0.5222       0    -0.5
   -0.12031      1.32943       0     1.5
   -0.17409     -0.38358       0    -0.5
    -0.7247     -0.64442    -0.5    -0.5
    0.07383      0.72742       0     0.5
    0.65539     -0.43668     0.5    -0.5
    0.29549     -1.36966     0.5    -1.5
    0.42063      0.09356     0.5       0
   -0.29958      0.90413    -0.5       1
   -1.38486      0.09106    -1.5       0
   -1.17443     -1.05509      -1      -1
    0.39475      2.28522     0.5     2.5
   -1.56378      0.13773    -1.5       0
    0.78106     -0.57944       1    -0.5
   -0.23633     -0.29939       0    -0.5
   -2.46887     -1.10493    -2.5      -1
     0.2432      0.95752       0       1
   -1.17685     -0.18723      -1       0
   -0.87421      1.57601      -1     1.5
    0.13451      1.45095       0     1.5
    1.30804     -0.19011     1.5       0
   -0.33474      0.46294    -0.5     0.5
    -0.2019     -0.17617       0       0
    1.21101     -1.40174       1    -1.5
    0.68958      0.01745     0.5       0
   -0.37379     -1.49588    -0.5    -1.5
     -0.787        0.656      -1     0.5
   -0.86297     -0.19319      -1       0
    0.61641     -0.73194     0.5    -0.5
    2.05304      0.68991       2     0.5
   -1.33063     -0.87794    -1.5      -1
   -1.36443      2.42907    -1.5     2.5
   -0.29668     -1.22439    -0.5      -1
   -0.49331     -0.83516    -0.5      -1
    0.02861      0.03971       0       0
    1.12641     -1.61266       1    -1.5
    0.47845     -1.47755     0.5    -1.5
   -0.17544      0.60136       0     0.5
    0.48128      0.11637     0.5       0
    0.67158      0.37892     0.5     0.5
     1.5482     -0.33739     1.5    -0.5
    1.37694     -0.60209     1.5    -0.5
   -0.54218     -0.74479    -0.5    -0.5
    0.56447      0.05115     0.5       0
    -0.1569     -1.19264       0      -1
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