Data collected from 642 Japanese corporations were applied to the Arbitrage Pricing Theory (APT) to clarify if it will be appropriate to Japanese firms. the results analyzed did not coincide with the estimation of APT. We constructed a new model, the Linear Structural Relational (LISREL) Model with fuzzy linear regression analysis, which is able to indentify each factor affecting the investment rate to common stocks. Four specific corporations were selected and data of balance sheets, income statements and so forth for 8-10 years were applied to the model. We found out that the model predicted the trend of these companies.