本研究係以路徑蒐尋網路分析的方法來評量學生在天文學習上的知識結構。參與受試的樣本，包括了4個老師及45個國小六年級的學生。在這45個學生中，有23個是自然科學成續表現在其班上排名前3至4名的學生，屬自然科學高成就者，另有22個是自然科學成續表現在其班上排名後3至4名的學生，屬自然學低成就者。所有的參與者均需對研究者就國小課程內所選出的九個天文名詞概念（太陽、地球、月球、火星、恆星、行星、衛星、流星及銀河系），進行判斷，判斷兩兩概念之間的關係。再藉由路徑尋量尺化算則，針對受試者的評估後資料，計算其知識表徵之網路結構。然後，利用PRX、GTD及PFC三個相似性指數，去評量每個學生的知識表徵網路結構與老師專家參照知識網路結構間的相似情形。主要的發現為（1）自然科學高成就學生的天文概念知識結構比自然科學低成就學生，更接近老師的知識結構。（2）男學生的天文概念知識結構與老師的知識結構間的相似度，與女學生的天文概念知識結構和老師知識結構的相似度，並無明顯地差異存在。（3）以相似性PRX、GTD及PFC三個指數來預測學生在自然科學學業成績上的表現，以PRX的預測力最好。

This study used the Pathfinder Network to assess student knowledge structure of astronomy learning. The subjects included four teachers, 23 high achievement sixth-graders, and 22 low achievement sixth-graders in natural science. All participants judged the relatedness of nine of the important concepts in astronomy learning. Network representations of the rating data were derived using the Pathfinder scaling algorithm. The similarity between each student’s and the teachers’ networks was then assessed using PRX, GTD, and PFC. The main findings were as follows：（1）The knowledge structures of students with high natural science achievement were closer to the teachers referent structure than those of the students with low achievement. （2）The student-teacher similarity had no significant difference by student’s gender comparison. （3）The PRX index was the most predictive of students’ natural science score among the three indices.