Commit 9b8ebd89ce46b3662f1538805d0c9d2184f02459

Authored by Francisco Coelho
1 parent 87b4cf2d
Exists in master

progress pre-paper, eq.rel defn, examples

text/paper_01/pre-paper.pdf
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text/paper_01/pre-paper.tex
... ... @@ -47,13 +47,14 @@
47 47 \newcommand{\ent}{\ensuremath{\lhd}}
48 48 \newcommand{\cset}[2]{\ensuremath{\set{#1,~#2}}}
49 49 \newcommand{\langof}[1]{\ensuremath{\fml{L}\at{#1}}}
50   -\newcommand{\uset}[1]{\ensuremath{\left|{#1}\right>}}
51   -\newcommand{\lset}[1]{\ensuremath{\left<{#1}\right|}}
  50 +\newcommand{\uset}[1]{\ensuremath{\left<{#1}\right|}}
  51 +\newcommand{\lset}[1]{\ensuremath{\left|{#1}\right>}}
52 52 \newcommand{\pr}[1]{\ensuremath{\mathrm{P}\at{#1}}}
53   -\newcommand{\class}[1]{\ensuremath{\nicefrac{#1}{\sim}}}
54   -\newcommand{\urep}[1]{\ensuremath{\nicefrac{#1}{\varnothing}}}
55   -\newcommand{\lrep}[1]{\ensuremath{\nicefrac{\varnothing}{#1}}}
56   -\newcommand{\rep}[2]{\nicefrac{#1}{#2}}
  53 +\newcommand{\class}[1]{\ensuremath{{#1}/_{\!\sim}}}
  54 +\newcommand{\urep}[1]{\ensuremath{\rep{#1}{}}}
  55 +\newcommand{\lrep}[1]{\ensuremath{\rep{}{#1}}}
  56 +\newcommand{\rep}[2]{\left\langle #1 \middle| #2 \right\rangle}
  57 +\newcommand{\inconsistent}{\otimes}
57 58 \newcommand{\given}{\ensuremath{~\middle|~}}
58 59 \newcommand{\todo}[1]{\textbf{\color{orange}~(~#1~)~}}
59 60  
... ... @@ -174,25 +175,33 @@ Given an ASP specification, we consider the \textit{atoms} $a \in \fml{A}$ and \
174 175 Out path starts with a perspective of stable models as playing a role similar to \textit{prime} factors. The stable models of specification are the irreducible events entailed from that specification and any event must be interpreted under its relation with the stable models. This stance leads to definition \ref{def:rel.events}:
175 176  
176 177 \begin{definition}\label{def:rel.events}
177   - Let $u,v \in \fml{E}$, and $\fml{S}, \fml{W}$ the set of stable models, resp. consistent events, of some specification. Define
  178 + Let $e, u, v \in \fml{E}$, and $\fml{S}, \fml{W}$ the set of stable models, resp. consistent events, of some specification. Define
178 179  
179 180 \begin{equation}
  181 + \uset{e} = \set{s \in \fml{S} \given e \subseteq s},
  182 + \end{equation}
  183 + \begin{equation}
  184 + \lset{e} = \set{s \in \fml{S} \given s \subseteq e}
  185 + \end{equation}
  186 +and
  187 + \begin{equation}
180 188 u \sim v \iff u,v \not\in\fml{W} \vee (\uset{u} = \uset{v} \wedge \lset{u} = \lset{v}).\label{eq:rel.events}
181 189 \end{equation}
182 190 \end{definition}
183 191  
184 192 This equivalence relation defines a partition of the events space, where each class holds a unique relation with the stable models. In particular, we can denote each class by
185 193 \begin{equation}
186   - \class{e} = \begin{cases}
187   - \star &\text{if~} e \in \fml{E} \setminus \fml{W}, \\
188   - \rep{\uset{e}}{\lset{e}} &\text{otherwise}.
  194 + \class{e} =
  195 + \begin{cases}
  196 + \inconsistent &\text{if~} e \in \fml{E} \setminus \fml{W}, \\
  197 + \rep{e}{e} &\text{otherwise}.
189 198 \end{cases}
190 199 \end{equation}
191 200  
192 201 Consider the example from \ref{eq:example.1}. The stable models are $\fml{S} = \co{a}, ab, ac$ so the quotient set of this relation is
193 202 \begin{equation}
194 203 \begin{aligned}
195   - &\star, \urep{\varnothing}, \
  204 + &\inconsistent, \rep{}{}, \
196 205 &\rep{\co{a}}{\co{a}} = \set{\co{a}}, \rep{ab}{ab} = \set{ab}, \rep{ac}{ac} = \set{ac}\\
197 206 &\urep{\co{a}}, \urep{ab}, \urep{ac}, \lrep{\co{a}}, \lrep{ab}, \lrep{ac}, \\
198 207 &\urep{\co{a}, ab}, \urep{\co{a}, ac}, \urep{ab, ac},
... ... @@ -201,13 +210,13 @@ Consider the example from \ref{eq:example.1}. The stable models are $\fml{S} = \
201 210 \end{aligned}
202 211 \end{equation}
203 212  
204   -For example, $\class{a} = \urep{ab, ac}$, $\class{abc} = \lrep{ab, ac}$ and $\class{bc} = \urep{\varnothing}$.
  213 +For example, $\class{a} = \urep{ab, ac}$, $\class{abc} = \lrep{ab, ac}$ and $\class{bc} = \rep{}{}$.
205 214  
206 215  
207 216 \begin{itemize}
208 217 \item Since all events within a equivalence class have the same relation with the stable models, probability assignment should be constant for the elements of that class.
209 218 \item So, instead of dealing with $2^6$ events, we need only to handle $19$ classes, well defined in terms of combinations of the stable models.
210   - \item The probability events are going to be the \textit{classes}.
  219 + \item The extended probability \textit{events} are the \textit{classes}.
211 220 \item The physical system might have \textit{latent} variables, possibly also represented in the specification. These variables are never observed, so observations should be concentrated in the $\nicefrac{\uset{e}}{\varnothing}$ classes.
212 221 \end{itemize}
213 222  
... ...