政治知識之於民主社會有其重要性，在政治學界中與政治知識相關的研究產出相當豐富，研究者利用政治知識此一變數進行相關研究前，對於題目如何選定、選項如何提供、題型的差異都是研究者需要去關注的重點，而本文主要的研究目的即是聚焦於討論何種題型更適合用來測量民眾的政治知識。 目前國內測量政治知識的問卷題型較為常見的為開放題與選擇題題型，在這兩類題型的討論上，前者被認為會低估受訪者政治知識程度，後者的測量結果則被質疑提供猜題空間導致高估了受訪者的政治知識程度，然而目前國內外卻缺乏足夠的實證研究來證明這兩個題型的適用性。 本文採用具有實驗設計性質的二手資料，利用前後測的方式讓受測者填答相同題目不同題型的問卷，藉此檢視各種知識程度的受測者在面對不同題型時是否會產生回應模式上的差異。本研究發現，開放題會使得較高政治知識程度的受訪者被低估，選擇題反而能準確測量出此類受訪者的知識程度。為了進一步證實受訪者在偏難的題目上所增加的猜題比例並非是來自於盲猜，本文採用多項機率單元模型來檢視受訪者於於選擇題選擇各個答項的機率。研究發現，儘管選擇題無法避免受訪者猜題，但受訪者並非是盲猜，反而會根據其具有的知識依據來答題，故政治知識程度高的受訪者能採用猜題方式答對題目，政治知識低的受訪者無法利用猜題方式猜中答案。整體而言，選擇題比起開放題更適合用來測量民眾的政治知識。 / Political knowledge plays an important role in the democratic society, and therefore there has been much research on political knowledge in the discipline of political science. To study political knowledge, political scientists have to understand the way of questions and options presented, and also the differences between a variety of question formats. This paper aims to analyze which question format is better for measuring the political knowledge of the public. The open-ended and multiple-choice items are both common formats for measuring political knowledge in Taiwan. The open-ended question is always considered to underestimate the respondents’ level of political knowledge, while the multiple-choice format is thought of overestimating the levels of political knowledge for providing the respondents with opportunity to guess. However, a strong evidence to decide the most suitable format for the measurement of political knowledge is still lacking. This paper uses the secondary data which is collected by a pretest-posttest questionnaire to examine whether guessing behavior will emerge or not when the respondents facing the same question with different formats. This research finds that open-ended questions underestimate the respondents’ knowledge levels who has higher level of political knowledge originally, but the multiple-choice questions can estimate the levels more accurately. To further confirm that the higher guess proportions in the more difficult questions are not resulted from the blind guessing, the study examines the probabilities of options selected by Multinomial Probit Model. The research finds that though the respondents may have guess more in multiple-choice question, however, they tend to answer the questions based on their knowledge instead of blind guessing. Therefore, the respondents who have higher levels of political knowledge can guess correctly, while those who have lower levels of political knowledge cannot. In summary, the multiple-choice questions are more suitable to measure people’s political knowledge.