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生成式人工智能的演进:从规则到推理
AI011Lesson 1
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生成式人工智能的演进:从规则到推理

人工智能的历史以一次根本性转变为标志:从明确的人类编程转向基于模式的统计预测。这一演进使现代人工智能能够完成复杂的 推理 任务。

1. 什么是:规则驱动时代

早期人工智能依赖于 专家系统。在这些系统中,每一个可能的响应或操作都是由人类手动编写代码实现的,采用严格的 如果-那么逻辑

  • 局限性: 这些系统非常脆弱。它们无法处理细微差别、俚语、拼写错误,也无法应对超出其特定硬编码程序范围的任何情况。

2. 为什么:统计突破

突破来自于处理海量未标注数据的能力。与人工规则不同, 大型语言模型(LLMs) 学习词语之间的统计关系。

  • Transformer: 一种于2017年推出的革命性模型架构。
  • 注意力机制: Transformer的核心组件,使模型能够对序列中不同词语的重要性进行加权,从而理解深层上下文(例如,知道长段落中的“它”指代什么)。

3. 如何:从预测到推理

现代生成式人工智能本质上是 非确定性的。它计算的是“下一个标记”的概率分布,而不是遵循固定的决策树。

通过反复基于全部前序上下文预测最有可能的下一个词,模型生成创造性内容,并似乎能“推理”自然语言提供的复杂指令。

概率陷阱
人工智能并非事实数据库;它是一个统计引擎。因为它仅仅预测最可能的下一个词,因此容易陷入 “幻觉”——以绝对自信的姿态呈现虚假信息。
evolution_logic.py
TERMINALbash — 80x24
> Ready. Click "Run" to execute.
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Question 1
What is the primary difference between rule-based chatbots and modern Generative AI?
Rule-based bots use neural networks, while GenAI uses decision trees.
Rule-based bots follow fixed scripts, while GenAI predicts responses based on patterns and probability.
Rule-based bots can reason, while GenAI only retrieves facts.
There is no difference; they are just different marketing terms.
Question 2
What does the 'Attention Mechanism' in a Transformer model do?
It ensures the user is paying attention to the output.
It searches the internet for the most accurate facts.
It allows the model to weight the importance of different parts of the input text.
It translates the text into binary code.
Challenge: Designing a Tutoring App
Apply your knowledge of AI evolution.
You are designing a tutoring app. You need to choose between a rule-based "if-then" system and an LLM.
Task 1
Identify a scenario where the rule-based system would fail but the LLM would succeed.
Solution:
Handling a student asking the same question in a creative or slang-heavy way (e.g., "Yo, how do I do math?" vs "Please explain the equations."). A rule-based system would likely throw an error if the exact phrasing wasn't programmed.
Task 2
Suggest a "Metaprompt" to ensure the LLM doesn't just give the answer but acts like a tutor.
Solution:
"You are a helpful tutor. Do not provide direct answers. Instead, ask leading questions to help the student find the solution themselves."