求概括strcuture和reduced form model主要区别

问题如下：

Tim and Wang are two junior credit analysts in a wealth management firm. They are estimating the probability of default of a set of bonds. Tim knows that 2 methods, structural model and reduced-form model could be used to estimate the probability of default.

For the reduced the model, Tim made the following statements:

Tim’s statement 1: Reduced-form model is based on the premise that a firm defaults on its debt if the value of its assets falls below its liabilities and that the probability of that event has the characteristics of an option.

Tim’s statement 2: For the reduced-form model, inputs are observable variables, including historical data. Thus, a reduced-form credit model involves regression analysis using information generally available in the financial markets.

According to the information above, which statement is correct?

选项：

Tim’s statement 1 is correct.

Tim’s statement 2 is correct.

both of the statements are correct.

解释：

B is correct.

考点：考察对Structural model/Reduced-form model的理解

解析：第一个Statement陈述的是Structural model的特征。