chapter 1 Flashcards
(30 cards)
singularity
a time in the near future when computers will become smarter than humans
empowered by its ability to improve itself and learn on its own, will quickly reach, and then exceed, human-level intelligence
Usual worries about AI
that increasingly sophisticated AI will replace humans in some jobs, that AI applied to big data sets could subvert privacy and enable subtle discrimination, and that ill-understood AI systems allowed to make autonomous decisions have the potential to cause havoc
Hofstadter’s worries about AI
terrified that intelligence, creativity, emotions, and maybe even consciousness itself would be too easy to produce—that what he valued most in humanity would end up being nothing more than a “bag of tricks,” that a superficial set of brute-force algorithms could explain the human spirit.
McCarthy
persuaded Minsky, Shannon, and Rochester to help him organize “a 2 month, 10 man study of artificial intelligence
The proposed study was based on “the conjecture that every aspect of learning or any other feature of intelligence can be in principle so precisely described that a machine can be made to simulate it.”
obstacles
- The Rockefeller Foundation came through with only half the requested amount of funding.
- It turned out to be harder than McCarthy had thought to persuade the participants to actually come and then stay/agree on anything.
- not a lot of coherence
(funding, participants, coherence)
suitcase word
terms that are packed like a suitcase with a jumble of different meanings
> like intelligence, thinking, cognition, consciousness, and emotion.
AI focused on two efforts
- Scientific:
investigate mechanism of natural (biological) intelligence by trying to embed it in computers - Practical:
create computer programs that do tasks as well or better than humans
(no worries abt if programs actually think like we think)
An anarchy of methods
different opinions about the correct approach to take to develop AI.
- mathematical logic and deductive reasoning as the language of rational thought
- Inductive methods: extract statistics from data and use probabilities to deal with uncertainty
- Biology and psychology: create brain like programs
current dominant paradigm = deep learning
machine learning
a subfield of AI in which machines “learn” from data or from their own “experiences.”
AI > machine learning > deep learning
AI
field that includes broad set of approaches, with the goal of creating machines with intelligence
symbolic AI
A symbolic AI program’s knowledge consists of
- words or phrases (the “symbols”), typically understandable to a human
- rules by which the program can combine and process these symbols in order to perform its assigned task.
General Problem Solver
Simon and Newell designed their program to mimic what they believed were the students’ thought processes.
At each step in its procedure, GPS attempts to change its current state to make it more similar to the desired state.
GPS
what are operators, rules, and arguments
operators (in the form of subprograms) can transform the current state into a new state
rules encode the constraints of the task.
Arguments are the words inside the parentheses
Advocates of the symbolic approach to AI argued that to attain intelligence in computers …
it would not be necessary to build programs that mimic the brain.
Instead, general intelligence can be captured entirely by the right kind of symbol-processing program.
most notable form of symbolic AI
expert systems
in expert systems, human experts devised rules for computer programs to use in tasks
such as medical diagnosis and legal decision-making
Symbolic AI was originally inspired by …
- mathematical logic
- the way people described their conscious thought processes
subsymbolic AI took inspiration from…
neuroscience:
sought to capture the sometimes-unconscious thought processes underlying what some have called fast perception
> such as recognizing faces or identifying spoken words
a subsymbolic program is…
essentially a stack of equations—a thicket of often hard-to-interpret operations on numbers
such systems are designed to learn from data how to perform a task
perceptron
invented by Frank Rosenblatt.
inspired by the way in which neurons process information.
perceptron neuron analogy
the perceptron adds up its inputs
if the resulting sum is equal to or greater than the perceptron’s threshold, the perceptron outputs the value 1 (it “fires”); otherwise it outputs the value 0 (it “does not fire”).
A perceptron’s threshold is simply a number set by the programmer
To simulate the different strengths of connections to a neuron
a numerical weight is assigned to each of a perceptron’s inputs; each input is multiplied by its weight before being added to the sum.
how do perceptrons learn
supervised learning
perceptrons should learn via conditioning
should be trained on examples: it should be rewarded when it fires correctly and punished when it errs.
supervised learning
the learning system is given an example
it produces an output
it is then given a “supervision signal,” which tells how much the system’s output differs from the correct output.
The system then uses this signal to adjust its weights and threshold.
training set
part of a set of labeled positive and negative examples to train the system with