Evaluation of the subseasonal forecast skill of surface soil moisture in the S2S database

Based on the reforecasts from ve models of the Subseasonal to Seasonal(S2S)Prediction project,the S2S prediction skill of surface soil moisture(SM)over East Asia during May September is evaluated against ERA-Interim.Results show that good prediction skill of SM is generally 510 forecast days prior over southern and northeastern China in the majority of models.Over the Tibetan Plateau and northwestern China,only the ECMWF model has good prediction skill 20 days in advance.Generally,better prediction skill tends to appear over wet regions rather than dry regions.In terms of the seasonal variation of SM prediction skill,some diffierences are noticed among the models,but most of them show good prediction skill during September.Furthermore,the significant positive correlation between the prediction skill of SM and ENSO index indicates modulation by ENSO of the S2S prediction of SM.When there is an El Nino(a La Nina)event,the SM prediction skill over eastern China tends to be high(low).Through evaluation of the S2S prediction skill of SM in these models,it is found that the prediction skill of SM is lower than that of most atmospheric variables in S2S forecasts.Therefore,more attention needs to be given to the S2S forecasting of land processes.

Research and Design of the Adaptive Evaluation System Based on the IRT Theory

This paper, on the basis of the author realizing the skill evaluation system based on real environment, discusses several commonly used parameter estimation methods based on item response theory （ IRT ） and analyzes the advantages and disadvantages of each estimation method and their respective application fields. Also, it expounds the research theory and design process of skill adaptive evaluation system based on real environment and the innovation of the system.

Investigating the Effectiveness of Peer Feedback on Writing from Stu⁃dents’Perspective:A Case Study in Scientia Secondary School,Hong Kong

This paper demonstrates students’perspective of peer feedback on writing.The researcher based on the relevant litera⁃ture to find that peer feedback has a great effect on learning engagement,evaluation skill,and peer interaction.However,there are still some doubts from teacher and student.Therefore,the researcher further reexamines this issue by conducting a pre-test,posttest with 36 students in Hong Kong,supplemented by interview data.The research findings suggest that numerous students notice the effectiveness of peer feedback whereas they are not familiar with the assessment process and technique.In this paper,the re⁃searcher will explore secondary students’perspective of peer feedback,and evaluate to what extent peer feedback can enhance their writing.Besides,there are some strategies for how to carry out peer feedback in writing class.