美国作业：Artificial Intelligence人工智能课后题目

Q1:We assumpt that a1 represents people are healty,and a2 imply people are unhealty, and b1 represents that blood test is positive, and b2 imply the test is negative. From the question, we know that p(b1|a2) = 0.9 and p(b1|a1) = 0.03; and that p(a1) = 0.9 and p(a2) = 0.1. We wantta know the probability that a person whos tests positive will have the disease. That means caculate p(a2|b1), and it equate p(a2b1)/p(b1). And p(a2b1) = p(b1|a2)p(a2) = 0.9*0.1, and p(b1) = p(b1|a1) + p(b1|a2) = 0.93. Then the result is 0.09/0.93, that's 0.096774.Q1：我们假设a1代表人们是健康的，a2意味着人们是不健康的，而b1代表血液测试是积极的，而b2意味着测试是消极的。从这个问题，我们知道p（b1 | a2）= 0.9，p（b1 | a1）= 0.03;并且p（a1）= 0.9并且p（a2）= 0.1。我们想知道测试阳性的人患这种疾病的可能性。这意味着计算p（a2 | b1），它等于p（a2b1）/ p（b1）。并且p（a2b1）= p（b1 | a2）p（a2）= 0.9 * 0.1，并且p（b1）= p（b1 | a1）+ p（b1 | a2）= 0.93。然后结果是0.09 / 0.93，即0.096774。

Q2:Rapid prototyping is a software development technique. And it is important in buiding the expert system because it can demonstrate the feasibility of the system. Rapid prototyping seems to be an appropriate strategy-especially given the usual vagueness of the understanding of what can be accomplished. In contrast to the waterfall model, which emphasizes rigorous specification and planning, RP approaches emphasize the necessity of adjusting requirements in reaction to knowledge gained as the project progresses. Q2：快速原型设计是一种软件开发技术。并且它在建立专家系统中很重要，因为它可以证明系统的可行性。快速原型设计似乎是一种合适的策略 - 特别是考虑到对可以实现的目标的理解通常含糊不清。与瀑布模型相比，瀑布模型强调严格的规范和规划，RP方法强调在项目进展过程中对调整所需知识的需求进行调整的必要性。

AI includes many specific techniques, which can assist the RP to some extent. For instance, techniques for ranking and selecting critical parameters system can help software development enviroment choose optimized parameter to prompt the rapid prototyping, and knowledge-based and expert system can assist the rapid prototyping by detecting the error in the process of rapid prototyping.AI包含许多特定技术，可以在一定程度上协助RP。例如，用于排序和选择关键参数系统的技术可以帮助软件开发环境选择优化参数以促进快速原型设计，并且基于知识和专家系统可以通过检测快速原型制作过程中的错误来辅助快速原型设计。

 

Q3: In my opition, the AI will have a bright future. As we know that AI now is a very hot area of computer science since it overcome the black era during 80s. Recently, Google , Facebook and other big companies all put numerous money in this area, these investment along with the efforts of researchers will all boost the development of AI.