蓝色 发表于 2013-1-22 23:29 
中值不明确
到底是中位数还是平均数没说明白
如果中位数r(p50)
你好!我想请教一下,我使用 foreach var of varlist size1 size2 Q lev cashflow1 cashflow2{
qui sum `var'
qui replace `var'=r(p50) if `var'==.
}想用中位数代替缺失值。
今天死活做不出来,运行完后缺失值依然是缺失值。而且我的数据有240多个,缺失值只有6个。
这是怎么回事呢?谢谢了!
贴部分数据:
size1 size2 Q lev cashflow1 cashflow2
21.98493 15.56308 615.1412 .6338399 .0290478 .0290478
20.05844 15.28316 118.5428 .3714112 .0727195 .0727195
21.99817 15.62234 587.4711 .5741621 -.0018139 -.0018139
22.12041 15.96219 472.5853 .1084521 .0774168 .0774168
20.94464 15.0745 354.3003 .2246548 .0592012 .0592012
22.35971 16.36205 402.4864 .4460558 .2161 .2161
21.2866 15.45338 341.458 .6156263 .0711398 .0711398
20.36624 14.2183 467.7512 .6032112 .0444179 .0444179
21.30594 15.08393 503.7152 .4176898 -.326143 -.326143
21.3845 14.55873 921.2807 .5482839 .0366629 .0366629
22.46421 15.82478 764.6597 .4085085 .0795146 .0795146
22.6102 15.94236 786.6886 .5526364 .0232512 .0232512
22.39297 15.94287 632.7599 .6444714 .0081571 .0081571
21.73352 15.53128 493.8525 .4574471 .0513462 .0513462
21.52264 14.81403 819.432 .5783805 -.0149195 -.0149195
21.72838 15.76604 388.5193 .5982122 .0821562 .0821562
20.94867 14.6876 523.7808 .1568577 .0140323 .0140323
21.37641 15.28368 442.6289 .4728863 -.1577941 -.1577941
21.3845 14.55873 921.2807 .5482839 .0366629 .0366629
20.90029 14.62553 531.0014 .4382796 .0330225 .0330225
21.01141 15.46401 256.5718 .2783067 -.0712376 -.0712376
21.568 15.70843 350.5706 .1487512 .096156 .096156
21.568 15.70843 350.5706 .1487512 .096156 .096156
20.3119 14.75053 260.1789 .4756629 .0577797 .0577797
22.49552 16.47463 411.944 .1927215 .1263439 .1263439
19.58948 14.26239 205.8396 .2020397 .0970683 .0970683
22.76931 15.25933 1826.186 .552344 -.0391131 -.0391131
21.35535 14.63891 825.8737 .3490112 -.002432 -.002432
20.81857 14.16129 778.4304 .5880712 .045874 .045874
20.48084 14.75865 305.5751 .6206105 -.0562396 -.0562396
21.35535 14.63891 825.8737 .3490112 -.002432 -.002432
21.95305 15.04142 1003.889 .3523054 .0475857 .0475857
21.50359 14.60806 987.8522 .4986708 .0291671 .0291671
22.64754 15.63961 1105.374 .5763695 .0724244 .0724244
21.54146 14.80016 846.6584 .2774114 .0997353 .0997353
21.92379 14.77851 1268.106 .6533401 .1463276 .1463276
20.48035 14.54414 378.5001 .2085253 .148439 .148439
21.17341 14.80988 580.2875 .1310264 .020398 .020398
21.14944 14.34871 898.5077 .5842086 2.19e-06 2.19e-06
20.05008 14.18182 353.6334 .2552087 .0489784 .0489784
21.97574 14.64405 1527.963 .6059776 -.0229385 -.0229385
22.43033 15.55711 966.0496 .2654554 .0781926 .0781926
21.69691 14.4248 1439.58 .6676548 .0496528 .0496528
21.69691 14.4248 1439.58 .6676548 .0496528 .0496528
22.50724 16.36214 466.4271 .5165384 .0644062 .0644062
22.41019 15.19387 1361.459 .6298981 .0186649 .0186649
21.54282 14.33669 1347.663 .6798778 .1585178 .1585178
21.95305 15.04142 1003.889 .3523054 .0475857 .0475857
20.65058 14.88712 318.4488 .4341565 .1371 .1371
22.50724 16.36214 466.4271 .5165384 .0644062 .0644062
22.37035 14.78869 1961.877 .6272542 .0214854 .0214854
21.73371 15.46728 526.5913 .5880494 .0685749 .0685749
22.5167 15.64869 961.0281 .266629 .125736 .125736
22.5167 15.64869 961.0281 .266629 .125736 .125736
20.57666 13.81737 862.0303 .0972385 .0171197 .0171197
21.31186 14.24114 1177.007 .4005401 .0096917 .0096917
22.74213 15.92798 910.6343 .5256957 .0240327 .0240327
21.67479 14.71429 1054.165 .5674028 .024502 .024502
21.17778 14.83777 566.8057 .5845265 .178007 .178007
20.98868 14.41771 714.0572 .4185618 .0832671 .0832671
20.91476 14.05145 956.5347 .4025281 -.2129373 -.2129373
20.45098 14.00019 633.1988 .4834003 .1198615 .1198615
22.60703 16.27622 561.6107 .5242398 .0460361 .0460361
19.97556 13.78211 489.5326 .4273476 .0458877 .0458877
21.58113 14.97468 739.8464 .5056492 .0050734 .0050734
20.77296 14.13332 764.8163 .6573387 -.1861356 -.1861356
22.54051 15.01553 1853.772 .6543437 .0000787 .0000787
21.7596 13.77994 2920.958 .6603516 -.0517755 -.0517755
22.20797 15.37266 930.1182 .3265165 .0547632 .0547632
20.03316 13.29166 846.8332 .1874299 .0111867 .0111867
22.77027 16.30166 644.583 .4777001 .099325 .099325
谢谢啦!补充:我随意编了几个小数据试了一下,也是不行。