| Both sides previous revisionPrevious revisionNext revision | Previous revision |
| public:t-713-mers:mers-23:empiricism [2023/11/19 13:15] – [Worlds: How it Hangs Together] thorisson | public:t-713-mers:mers-23:empiricism [2024/04/29 13:33] (current) – external edit 127.0.0.1 |
|---|
| ====Worlds: How it Hangs Together==== | ====Worlds: How it Hangs Together==== |
| |
| | **W**: \\ A World | **W = { V,F,S0,R }** || | | **W**: \\ A World | **W = { V,F,S<sub>0</sub>,R }** || |
| | **V**: \\ Variables | **V = { v1, v2, . . . , v{||V||} }** || | | **V**: \\ Variables | **V = { v<sub>1</sub>, v<sub>2</sub>, . . . , v{||V||} }** || |
| | **F**: \\ Transition Functions | \\ **F** is a set of transition functions / rules describing how the variables can change. \\ The dynamics can intuitively be thought of as the world’s “laws of nature”, continually transforming the world’s current state into the next: **S{t+δ} = F(St)**. || | | **F**: \\ Transition Functions | \\ **F** is a set of transition functions / rules describing how the variables can change. \\ The dynamics can intuitively be thought of as the world’s “laws of nature”, continually transforming the world’s current state into the next: **S{t+δ} = F(S<sub>t</sub>)**. || |
| | **C**: \\ A World Clock | The clock updates the Transition Functions. \\ In the physical world **C** updates **F** (including energy transfer), irrespective of anything and everything else that may happen in the World, constraining how much can happen for any time unit. || | | **C**: \\ A World Clock | The clock updates the Transition Functions. \\ In the physical world **C** updates **F** (including energy transfer), irrespective of anything and everything else that may happen in the World, constraining how much can happen for any time unit. || |
| | **S<sub>0</sub>**: \\ Initial State | **S0** is the State that **W** started out in. \\ In any complex world this is unlikely to be known; for artificial worlds this may be defined. || | | **S<sub>0</sub>**: \\ Initial State | **S<sub>0</sub>** is the State that **W** started out in. \\ In any complex world this is unlikely to be known; for artificial worlds this may be defined. || |
| | \\ **R**: \\ Relations | **R** are the relations between variables in the world. These may be unknown or partially known to an //Agent// in the world. || | | \\ **R**: \\ Relations | **R** are the relations between variables in the world. These may be unknown or partially known to an //Agent// in the world. || |
| | ::: | Static World | Changes //State// only through //Agent Action//. | | | ::: | Static World | Changes //State// only through //Agent Action//. | |
| | ::: | Dynamic World | Changes //State// through //Agent Action// and through other means. | | | ::: | Dynamic World | Changes //State// through //Agent Action// and through other means. | |
| | \\ State | **st in Vt**. A set of variables **x** with a set of values, specified to some particular precision (with constraints, e.g. error bounds), for relevant to a //World//. \\ For all practical purposes, in any complex World "State" refers by default to a sub-state, since it is a practical impossibility to know its full state (values of the complete set of variables) of a world; there will always be a vastly higher number of "don't care" variables than the variables listed for e.g. a //Goal State// (a //State// associated with a //Goal//). || | | \\ State | **s<sub>t</sub> in V<sub>t</sub>**. A set of variables **x** with a set of values, specified to some particular precision (with constraints, e.g. error bounds), for relevant to a //World//. \\ For all practical purposes, in any complex World "State" refers by default to a sub-state, since it is a practical impossibility to know its full state (values of the complete set of variables) of a world; there will always be a vastly higher number of "don't care" variables than the variables listed for e.g. a //Goal State// (a //State// associated with a //Goal//). || |
| | | \\ State \\ definition | **st in Vt** \\ where \\ **{ xl, xu } | {xl =< x =< xu}** \\ \\ define lower (**xl**) and upper (**xu**) bounds on acceptable range for each **x** to count towards the State, respectively. | | | | \\ State \\ definition | **s<sub>t</sub> in V<sub>t</sub>** \\ where \\ **{ x<sub>l</sub>, x<sub>u</sub> } | {x<sub>l</sub> =< x =< x<sub>u</sub>}** \\ defines lower (**x<sub>l</sub>**) and upper (**x<sub>u</sub>**) bounds on acceptable range for each **x** to count towards the State, respectively. | |
| | Exposable Variables | Variables in **V** that are measurable and/or manipulatable //in principle//. || | | Exposable Variables | Variables in **V** that are measurable and/or manipulatable //in principle//. || |
| | Observable Variables | Variables in **V** that can be measured for a particular interval in time are //observable// during that interval. || | | Observable Variables | Variables in **V** that can be measured for a particular interval in time are //observable// during that interval. || |
| |
| ====Maxwell's Demon==== | ====Maxwell's Demon==== |
| | {{public:t-720-atai:maxwellsdemon.png?500}} \\ Source: [[https://en.wikipedia.org/wiki/Maxwell%27s_demon|Wikipedia]] \\ By User:Htkym - Own work, CC BY 2.5, [[https://commons.wikimedia.org/w/index.php?curid=1625737|REF]] || | | {{public:t-720-atai:maxwellsdemon.png?500}} \\ Source: [[https://en.wikipedia.org/wiki/Maxwell%27s_demon|Wikipedia]] \\ By User: Htkym - Own work, CC BY 2.5, [[https://commons.wikimedia.org/w/index.php?curid=1625737|REF]] || |
| | \\ A Thought Experiment | Imagine a container divided into two parts, A and B. Both parts are filled with the same gas at equal temperatures and placed next to each other. Observing the molecules on both sides, an imaginary demon guards a trapdoor between the two parts. When a faster-than-average molecule from A flies towards the trapdoor, the demon opens it, and the molecule will fly from A to B. Likewise, when a slower-than-average molecule from B flies towards the trapdoor, the demon will let it pass from B to A. The average speed of the molecules in B will have increased while in A they will have slowed down. Since average molecular speed corresponds to temperature, the temperature decreases in A and increases in B, contrary to the second law of thermodynamics. A heat extractor operating between the thermal reservoirs A and B could extract energy from this temperature difference, creating a perpetual motion machine. [ Adapted from [[https://en.wikipedia.org/wiki/Maxwell%27s_demon|Wikipedia]] ] | | | \\ A Thought Experiment | Imagine a container divided into two parts, A and B. Both parts are filled with the same gas at equal temperatures and placed next to each other. Observing the molecules on both sides, an imaginary demon guards a trapdoor between the two parts. When a faster-than-average molecule from A flies towards the trapdoor, the demon opens it, and the molecule will fly from A to B. Likewise, when a slower-than-average molecule from B flies towards the trapdoor, the demon will let it pass from B to A. The average speed of the molecules in B will have increased while in A they will have slowed down. Since average molecular speed corresponds to temperature, the temperature decreases in A and increases in B, contrary to the second law of thermodynamics. A heat extractor operating between the thermal reservoirs A and B could extract energy from this temperature difference, creating a perpetual motion machine. [ Adapted from [[https://en.wikipedia.org/wiki/Maxwell%27s_demon|Wikipedia]] ] | |
| | \\ The Error | The thought experiment is flawed because the demon must be part of the same system that the container is part of; thinking (or computation, if the demon is a robot) requires time and energy, and so whatever heat is saved in the container will be spent to run the demon's thinking processes. (This was first proposed in {{/public:t-720-atai:szilard-1929-entropy-intelligent-beings.pdf|"On the Decrease of Entropy in a Thermodynamic System | | \\ The Error | The thought experiment is flawed because the demon must be part of the same system that the container is part of; thinking (or computation, if the demon is a robot) requires time and energy, and so whatever heat is saved in the container will be spent to run the demon's thinking processes. (This was first proposed in {{/public:t-720-atai:szilard-1929-entropy-intelligent-beings.pdf|"On the Decrease of Entropy in a Thermodynamic System by the Intervention of Intelligent Beings" | 1929 by Leo Szilard}}.) | |
| by the Intervention of Intelligent Beings" | 1929 by Leo Szilard}}.) | | |
| |
| |
| |
| ====Empiricism==== | ====Empiricism==== |
| | What it is | The idea that all knowledge comes from experience -- the senses. | | | What it is | The idea that all knowledge comes from experience -- the senses. \\ In AI it also means that this experience comes from the physical world, through physical sensors. | |
| | Why it matters | Before the emphasis on empirical knowledge, science did not have a chance to rise in any obvious way above "other sources of knowledge," including old scriptures, intuition, religious beliefs, or information produced by oracles. | | | Why it matters | Before the emphasis on empirical knowledge, science did not have a chance to rise in any obvious way above "other sources of knowledge," including old scriptures, intuition, religious beliefs, or information produced by oracles. | |
| | Empiricism & Science | The fundamental source of information in (empirical, i.e. experimental) science is experience, which eventually became the formalized **comparative experiment**. | | | Empiricism & Science | The fundamental source of information in (empirical, i.e. experimental) science is experience, which eventually became the formalized **comparative experiment**. | |
| | [[https://sciencing.com/calculate-significance-level-7610714.html|Comparative Experiment]] | A method whereby two experimental conditions are compared, were they are identical except for one or a few strategic differences that the experimenters make. The outcome of the comparison is used to infer causal relations. Often called "the scientific method", this is the most dependable method for creating reliable, sharable knowledge that humanity has come up with. | | | \\ [[https://sciencing.com/calculate-significance-level-7610714.html|Comparative Experiment]] | A method whereby two experimental conditions are compared, were they are identical except for one or a few strategic differences that the experimenters make. The outcome of the comparison is used to infer causal relations. Often called "the scientific method", this is the most dependable method for creating reliable, sharable knowledge that humanity has come up with. | |
| | [[https://www.britannica.com/topic/logical-positivism|Logical Positivism]] | Philosophical school of thought closely related to empirical science. | | | [[https://www.britannica.com/topic/logical-positivism|Logical Positivism]] | Philosophical school of thought closely related to empirical science. | |
| | [[https://www.britannica.com/topic/rationalism|Rationalism]] | Historically a philosophically opposing view to empiricism, contending that knowledge is produced through innate knowledge, not through experience. | | | [[https://www.britannica.com/topic/rationalism|Rationalism]] | Historically a philosophically opposing view to empiricism, contending that knowledge is produced through innate knowledge, not through experience. | |
| | Theory | A scientific (empirical) theory is a "story" about how certain phenomena relate to each other. The more details, the more accurately, and the larger scope the theory covers, the better it is. | | | Theory | A scientific (empirical) theory is a "story" about how certain phenomena relate to each other. The more details, the more accurately, and the larger scope the theory covers, the better it is. | |
| | Hypothesis | A statement about how the world works, derived from a theory. | | | Hypothesis | A statement about how the world works, derived from a theory. | |
| | Experimental design | A planned interference in the natural order of events. | | | Experimental design | A planned interference in the natural order of events. | |
| | Subject(s) | Subject of interest - that to be studied, whether people, technology, natural phenomena, or other | | | Subject(s) | Subject of interest - that to be studied, whether people, technology, natural phenomena, or other | |
| | Sample | Typically you can't study all the **individuals** of a particular subject pool (set), so in your experiment you use a **sample** (subset) and hope that the results gathered using this subset generalize to the rest of the set (subject pool). | | | Sample | Typically you can't study all the **individuals** of a particular subject pool (set), so in your experiment you use a **sample** (subset) and hope that the results gathered using this subset generalize to the rest of the set (subject pool). | |
| | Between subjects vs. within subjects design | Between subjects: Two separate groups of subject/phenomena measured \\ Within subjects: Same subjects/phenomena measured twice, on different occasions | | | Between subjects vs. within subjects design | Between subjects: Two separate groups of subject/phenomena measured \\ Within subjects: Same subjects/phenomena measured twice, on different occasions | |
| | Quasi-Experimental | When conditions do not permit an **ideal** design to be used (a properly controlled experiment is not possible), there may still be some way to control some of the variables. This is called quasi-experimental design. | | | Quasi-Experimental | When conditions do not permit an **ideal** design to be used (a properly controlled experiment is not possible), there may still be some way to control some of the variables. This is called quasi-experimental design. | |
| | Dependent variable | The measured variable(s) of the phenomenon which you are studying | | | Dependent variable | The measured variable(s) of the phenomenon which you are studying | |
| | Independent variable | The variable(s) that you manipulate in order to systematically affect (or avoid affecting) the dependent variable(s) | | | Independent variable | The variable(s) that you manipulate in order to systematically affect (or avoid affecting) the dependent variable(s) | |
| | Internal validity | How likely is it that the manipulation of the independent variables caused the effect in dependent variables? | | | Internal validity | How likely is it that the manipulation of the independent variables caused the effect in dependent variables? | |
| | External validity | How likely is it that the results generalize to other instances of the phenomenon under study? | | | External validity | How likely is it that the results generalize to other instances of the phenomenon under study? | |
| |
| \\ | \\ |
| |
| ====Controlled Experiment==== | ====Controlled Experiment==== |
| | What is it? | A fairly recent research method, historically speaking, for testing hypotheses / theories | | | What is it? | A fairly recent research method, historically speaking, for testing hypotheses / theories | |
| | When | When it is possible to control and select everything of importance to the subject of study | | | When | When it is possible to control and select everything of importance to the subject of study | |
| | How | Select subjects freely, randomize samples, remove experimenter effect through double-blind procedure, use control groups, select independent and dependent variables as necessary to answer the questions raised. | | | How | Select subjects freely, randomize samples, remove experimenter effect through double-blind procedure, use control groups, select independent and dependent variables as necessary to answer the questions raised. | |
