本研究採Monte Carlo模擬的方式，探討四種連結方法對連結所產生的影響，以期對不同遲結方法的效益，提供清晰而深入的參考文獻，綜合三組資料，其主要發現如下： 一、無論標的量尺的題目參數、考生能力參數為真值或估計值，在最佳方法的選擇上並無不同，其推論是一致的，即普偏以特徵曲線轉換法的連結結果為佳。 　　二、就難度和鑑別度而言，在選擇最佳方法的推論，單就共同試題而言其推論並不一致，即平均數、標準差法和特徵曲線轉換法互有上下；但就新測而言，其推論是一致的，即以特徵曲線轉換法為佳。 　　三、就鑑別度而言，除組合三(題目參數連到估計值上且考生能力為真值)和組合四(題目參數連到估計值上且考生能力為估計值)以特徵曲線轉化法的結果優於連結前外，其餘的方法、組合連結後皆有系統高估的現象。 　　四、由共同試題和整個測驗來評估最佳方法時，在鑑別度方面是一致的，而難度方面其推論並不一致。 　　五、特徵曲線轉化法的優勢得到支持，尤其在鑑別度方面，或在整個測驗的評估上，其勢更為明顯。 　　六、平均數、標準差法的進結結果雖較特徵曲線轉化法稍遜，但計算簡便，有其存在的價值。

　　　　　The purpose of this study is to investigate the effects of IRT linking methods when the average ability of examinees for the new test is significantly higher than the average ability of the original norm. the IRT linking methods included are “mean and sigma”, “iterative mean and sigma”, “iterative robust mean and sigma” and “item characteristic curve”. Four linking settings for the target scale are (1) true values for the item and person parameters, (2) true values for the item parameters but estimated values for the person parameters, (3) estimated values for the item parameter but true values for the person parameters, and (4) estimated values for the item and person parameters. The true values of the item parameters (both for the anchor tests and the whole tests) are used as the criteria for evaluation. Three replications are implemented and the average results are presented. The evaluation of the linking effect is clearer and more optimistic than the results form the previous studies. No matter whether the parameters of the target scale are true values of estimated values, the inferences are in agreement. In other word, the inference made from the real world’s data will be valid for the true value. For both the difficulty, b, parameter and the discrimination, a, parameter, the best choice for linking is the method of “item characteristic curve” and “mean and sigma” depending on the criterion adopted. If judging form the whole test, the method of “item characteristic curve” is be the best choice. When the difficulty parameter of the anchor test it the method of “mean and sigma” performs best and the method of “item characteristic curve” is the second choice. Generally speaking, the method of “item characteristic curve” is recommended for the data sets simulated. Especially for the discrimination parameter, the method of “item characteristic curve” performs best consistently. The method of “mean and sigma” is recommend for its computation simplicity. Linking process decreases the scale difference which was caused by the different samples of examinees. Linking error is minor compared with the estimation error, especially for the difficulty parameter.