#!/usr/bin/env python
# coding: utf-8

# # Textbook Authors
# 
# [Stuart Russell](http://www.cs.berkeley.edu/~russell/) and [Peter Norvig](http://norvig.com/)
# 
# Where do and have they worked?  What are their main interests?

# # What is Artificial Intelligence?
# 
#   * Thinking
#     * like a human
#     * rationally---optimally, or the best possible
#   * Acting
#     * like a human
#     * rationally

# # Thinking Like a Human
# 
# How do humans think?
# 
# **Cognitive Science** is relatively new field that is trying to answer
# this question.
# 
#   * [Wikipedia entry for Cognitive Science](http://en.wikipedia.org/wiki/Cognitive_science)
#   * [Stanford Encyclopedia of Philosophy entry for Cognitive Science](http://plato.stanford.edu/entries/cognitive-science/)
#   * [Stanford Encyclopedia of Philosophy entry for Embodied Cognition](http://plato.stanford.edu/entries/embodied-cognition/)

# # Acting Like a Human
# 
# In the study of "intelligence", many aspects are missed if studied in
# isolation of human or robot bodies.
# 
# A true "artificial intelligence" must be capable of interacting with
# its world.
# 
# **Turing Test**: a computer is intelligent if a human interrogator,
# after posing some written questions, cannot tell whether the written
# responses come from a person or from a computer. 
# 
# [xkcd version](http://xkcd.com/329/) and [another one](http://xkcd.com/632/) (thanks Brock Wilcox)

# # Thinking Rationally
# 
# **Rationality**: doing the right thing, given what is known.
# 
# Logical reasoning systems.
# 
# Problems:
#   * hard to write informal knowledge as logical statements
#   * solving most logical reasoning problems currently takes too much time or memory.

# # Acting Rationally
# 
# **Agent**: computer programs that 
#   * operate autonomously
#   * perceive their environment
#   * persist over long time periods
#   * adapt to change
#   * create and pursue goals
# 
# **Rational agent**:  an agent that acts to achieve the best outcome, or best average outcome if the agent has incomplete knowledge
# 
# Russell and Norvig take the view of rational agents in describing data
# structures and algorithms.

# # History
# 
# [Wikipedia entry](http://en.wikipedia.org/wiki/History_of_artificial_intelligence#Dartmouth_Conference_1956:_the_birth_of_AI)

# # Early
# 
# <img src="https://www.cs.colostate.edu/~anderson/cs440/notebooks/historyearly.png">

# # Recent
# 
# 
# <img src="https://www.cs.colostate.edu/~anderson/cs440/notebooks/historyrecent.png">

# # Intelligent Agents
# 
# An **agent** "perceives its **environment** through **sensors** and
# acts upon that environment through **actuators**."  
# 
# <img src="http://www.cs.colostate.edu/~anderson/cs440/notebooks/agent1.png">
# 
# An agent's choice of action can depend on the entire history of
# percepts observed previously, but not on anything it has not
# perceived.

# # Rationality
# 
# But, which action to choose?  A **rational** agent is one that does
# the "right thing", which depends on the **performance measure**.
# 
# The performance measure should be designed to reflect what one
# actually wants in the environment, rather than how one suspects the
# agent should behave.  Define it in terms of effects of actions on the
# environment, rather than in terms of the agent's program.
# 
# Rational behavior is not perfect, because an agent cannot know
# everything about the environment, including past, present, and
# future.  We focus on maximizing **expected** performance, given what
# we know about probabilities of things happening in the environment.

# # Nature of Environments
# 
# Specify the task environment (PEAS):
#   * P: performance measure
#   * E: environment
#   * A: agent's actuators
#   * S: agent's sensors
# 
# 
# |  Agent Types  |  Performance Measure  |  Environment  |  Actuators  |  Sensors  |
# | --- | --- | --- | --- | --- |
# |  medical diagnosis system  |  healthy patient, reduced costs  |  patient, hospital, staff | display of questions, tests, diagnoses, treatments, referrals  |
# |  satellite image analysis system  |  correct image categorization   |  downlink from orbiting satellite  |  display of scene categorization  |  color pixel arrays  |
# |  part-picking robot  |  percentage of parts in correct bins  |  conveyor belt with parts; bins  |  jointed arm and hand  |  camera, joint angle sensors  |
# |  refinery controller  |  purity, yield, safety  |  refinery, operators  |  valves, pumps, heaters, displays  |  temperature, pressure, chemical sensors  |
# |  interactive English tutor  |  student's score on test  |  set of students, testing agency  |  display of exercies, suggestions, corrections  |  keyboard entry  |
# 
# 
# | Task Environment  |  Observable  |  Agents  |  Deterministic  |  Episodic  |  Static  |  Discrete  |
# | --- | --- | --- | --- | --- | --- | --- |
# |  crossword puzzle  |  fully  |  single  |  deterministic  |  sequential  |  static  |  discrete  |
# | chess with clock  |  fully  |  multi  |  deterministic  |  sequential  |  semi  |  discrete  |
# |  poker  |  partially  |  multi  |  stochastic  |  sequential  |  static  |  discrete  |
# |  backgammon  |  fully  |  multi  |  stochastic  |  sequential  |  static  |  discrete  |
# |  taxi driving  |  partially  |  multi  |  stochastic  |  sequential  |  dynamic  |  continuous  |
# |  medical diagnosis  |  partially  |  single  |  stochastic  |  sequential  |  dynamic  |  continuous  |
# |  image analysis  |  fully  |  single  |  deterministic  |  episodic  |  semi  |  continuous  |
# |  part-picking robot  |  partially  |  single  |  stochastic  |  episodic  |  dynamic  |  continuous  |
# |  refinery controller  |  partially  |  single  |  stochastic  |  sequential  |  dynamic  |  continuous  |
# |  interactive English tutor  |  partially  |  multi  |  stochastic  |  sequential  |  dynamic  |  discrete  |

# # Structure of Agents
# 
# Reflex agents
# 
# Model-based reflex agents
# 
# Goal-based agents
# 
# Utility-based agents
# 
# Using **learning** to modify each of the above.