sample evaluation造句

• At present causes of the difficulties in popularizing sample survey in small-sized commerce and trade firms lie in the following : the change of economy components and interest structure, many restrictions of survey funds and traditional sample survey model, severe short register or missing register, a lack of necessary sample evaluation, and the sample survey result's failure to meet the need of the management in various levels
  目前，导致小型商贸业抽样调查难以推广的主要原因是经济成分和利益格局的变化；受调查经费和抽样调查模式的约束较多；宣传与执法力度不够，少登漏记现象严重；对样本缺乏必要的评估；难以满足多层次管理目标的需要。