本研究之主要目的在於運用Ajzen(1985)的計劃行為論(the Theory of Planned Behavior)來預測並解釋本研究對象在上下學途中機車超速駕駛之意圖、行為及其影響因素。同時也比較理性行動論(the Theory of Reasoned Action)與計劃行為論兩者應用在上下學途中機車超速駕駛意圖及行為上的適切性。
本研究以私立華夏工商專校夜間部（二專）所有男生為母群體，以簡單隨機抽樣法抽出調查樣本進行施測。研究者依據開放式引導問卷填答結果篩選出顯著信念，編製而成正式問卷，二星期後追蹤行為。共得到638份有效問卷，行為追蹤則完成577人。
本研究結果如下：
一、本研究對象機車超速駕駛的行為可以由意圖和知覺行為控制來預測，行為意圖可解釋行為34.1%的變異量。而加入知覺行為控制後，共可解釋行為34.6%的變異量。
二、機車超速駕駛意圖受到態度、主觀規範、知覺行為控制三者的影響，三者可以解釋行為意圖39.9%的變異量。
三、態度與行為信念，結果評價的交乘積和(ΣBixEi)為中等程度的正相關；主觀規範與規範信念、依從動機的交乘積和(ΣNBjxMcj)呈中等程度的正相關；知覺行為控制與控制信念之間也是中等程度的正相關。
四、有／無機車超速駕駛意圖者在行為信念、結果評價、規範信念、依從動機、控制信念上有整體性的差異存在。
五、外在變項對機車超速駕駛意圖及行為均有直接的影響，且以過去超速駕駛經驗的影響最大，此一結果與理論的假設不符。
六、在預測機車超速駕駛意圖與行為方面，理性行動論本身即具有顯著的解釋力；而且發現計劃行為論應用在機車超速駕駛意圖及行為上的適切性優於理性行動論。

The purpose of this study aims to predict and explain the male students' intentions and behavior of motorcycle speeding on the basis of the Ajzen's Theory of Planned Behavior (TPB), and to compare the Theory of Reasoned Action (TRA) with TPB in terms of their ability to predict intentions and behavior.
Data are collected during questionnaire surveys on a cluster sample of 638 male students who operate motorcycles in a junior college. A follow-up interview of the sample is conducted approximately two weeks later. Self-reported data on subsequent motorcycle speeding behavior are Obtained from 577 of the 638 subjects, a 90.44% response rate.
The main findings of this study are as follows:
1. Perceived behavioral control and intentions are together moderately successful in predicting subjects' motorcycle speeding behavior. The intentions can explain 34.1% of behavior variance. It adds to 34.6% while incorporating perceived behavioral control.
2. The attitudes, subjective norms and perceived behavioral control can effectively predict the subjects' motorcycle speeding intentions. All can explain 39.9% of intention variance.
3. Attitudes, subjective norms, and perceived behavioral control are co-related to appropriate sets of salient behavioral, normative, and control beliefs about the behavior.
To sum up, the results of this study support the hypothesis of the TPB and reveal that the TPB permits more accurate prediction of intentions and behavior with respect to motorcycle speeding than TRA does.