errors-in-variables bias： 是在利用模型进行回归分析时在计量变量本身时发生的错误。主要指操作上出现的问题，例如漏了变量等,而不是说变量input选的不对

NO.PZ2016071602000008 问题如下 A tabase of hee funreturns is constructefollows. The first yeof the tabase is 1994. All fun existing of the enof 1994 tha willing to report their verifiereturns for thyeare incluin thyear. The tabase is extenasking the fun for verifiereturns before 1994. Subsequently, fun are aethey are willing to report verifiereturns to the tabase. If a funstops reporting returns, its returns are letefrom the tabase, but the tabase hagreement with fun ththey will keep reporting verifiereturns even if they stop being open to new investors. Whiof the following four statements are correct?I. The tabase suffers from backfilling bias.II. The tabase suffers from survivorship bias.III. The tabase suffers from errors-in-variables bias.IV. The equally weighteannureturn average of funreturns will unr-estimate the performanone woulexpefrom a hee fun A.All the above statements are correct. B.Statements I anII are correct. C.Statements I, II, anIII are correct. Statements II anIV are correct. B is correct. The tabase inclus histories before 1994 antherefore suffers from backfill bias. Next, fun thstop reporting are letefrom the tabase, so it hsurvivorship bias. Errors-in-variables biarises in other contexts, suregression. Finally, the average of funreturns will too high (not too low) because of these two biases. Hence, I. anII. are correct. 如题

NO.PZ2016071602000008 问题如下 A tabase of hee funreturns is constructefollows. The first yeof the tabase is 1994. All fun existing of the enof 1994 tha willing to report their verifiereturns for thyeare incluin thyear. The tabase is extenasking the fun for verifiereturns before 1994. Subsequently, fun are aethey are willing to report verifiereturns to the tabase. If a funstops reporting returns, its returns are letefrom the tabase, but the tabase hagreement with fun ththey will keep reporting verifiereturns even if they stop being open to new investors. Whiof the following four statements are correct?I. The tabase suffers from backfilling bias.II. The tabase suffers from survivorship bias.III. The tabase suffers from errors-in-variables bias.IV. The equally weighteannureturn average of funreturns will unr-estimate the performanone woulexpefrom a hee fun A.All the above statements are correct. B.Statements I anII are correct. C.Statements I, II, anIII are correct. Statements II anIV are correct. B is correct. The tabase inclus histories before 1994 antherefore suffers from backfill bias. Next, fun thstop reporting are letefrom the tabase, so it hsurvivorship bias. Errors-in-variables biarises in other contexts, suregression. Finally, the average of funreturns will too high (not too low) because of these two biases. Hence, I. anII. are correct. 老师这是什么偏差？

NO.PZ2016071602000008 问题如下 A tabase of hee funreturns is constructefollows. The first yeof the tabase is 1994. All fun existing of the enof 1994 tha willing to report their verifiereturns for thyeare incluin thyear. The tabase is extenasking the fun for verifiereturns before 1994. Subsequently, fun are aethey are willing to report verifiereturns to the tabase. If a funstops reporting returns, its returns are letefrom the tabase, but the tabase hagreement with fun ththey will keep reporting verifiereturns even if they stop being open to new investors. Whiof the following four statements are correct?I. The tabase suffers from backfilling bias.II. The tabase suffers from survivorship bias.III. The tabase suffers from errors-in-variables bias.IV. The equally weighteannureturn average of funreturns will unr-estimate the performanone woulexpefrom a hee fun A.All the above statements are correct. B.Statements I anII are correct. C.Statements I, II, anIII are correct. Statements II anIV are correct. B is correct. The tabase inclus histories before 1994 antherefore suffers from backfill bias. Next, fun thstop reporting are letefrom the tabase, so it hsurvivorship bias. Errors-in-variables biarises in other contexts, suregression. Finally, the average of funreturns will too high (not too low) because of these two biases. Hence, I. anII. are correct. 课上说的是插入了个新数据

NO.PZ2016071602000008问题如下 A tabase of hee funreturns is constructefollows. The first yeof the tabase is 1994. All fun existing of the enof 1994 tha willing to report their verifiereturns for thyeare incluin thyear. The tabase is extenasking the fun for verifiereturns before 1994. Subsequently, fun are aethey are willing to report verifiereturns to the tabase. If a funstops reporting returns, its returns are letefrom the tabase, but the tabase hagreement with fun ththey will keep reporting verifiereturns even if they stop being open to new investors. Whiof the following four statements are correct?I. The tabase suffers from backfilling bias.II. The tabase suffers from survivorship bias.III. The tabase suffers from errors-in-variables bias.IV. The equally weighteannureturn average of funreturns will unr-estimate the performanone woulexpefrom a hee funA.All the above statements are correct.B.Statements I anII are correct.C.Statements I, II, anIII are correct.Statements II anIV are correct.B is correct. The tabase inclus histories before 1994 antherefore suffers from backfill bias. Next, fun thstop reporting are letefrom the tabase, so it hsurvivorship bias. Errors-in-variables biarises in other contexts, suregression. Finally, the average of funreturns will too high (not too low) because of these two biases. Hence, I. anII. are correct.总是会混淆这两个bi 谢谢老师