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teaching:is:prop-rules-solutions [2020/05/21 16:53]
Franconi Enrico [5.1]
teaching:is:prop-rules-solutions [2020/06/24 10:06] (current)
Franconi Enrico [5.3]
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 (b) We would expect the user of the house to be able to determine whether the taps are on and whether the plugs are in or not. (b) We would expect the user of the house to be able to determine whether the taps are on and whether the plugs are in or not.
  
-<nowiki>(c)</nowiki>Here is the minimal set of clauses:+<nowiki>(c)</nowiki> Here is the minimal set of clauses:
 <code> <code>
 wet floor <- wet sink & plugged sink.  wet floor <- wet sink & plugged sink. 
Line 51: Line 51:
 ===== 5.3 ===== ===== 5.3 =====
 (a) Give a model of the model of the knowledge base: (a) Give a model of the model of the knowledge base:
- 
 The minimal model has { a, c, e, f, g } true and { b, d, h } false. Another model is where all atoms are true. The minimal model has { a, c, e, f, g } true and { b, d, h } false. Another model is where all atoms are true.
  
 (b) Give an interpretation that is not a model of the knowledge base: (b) Give an interpretation that is not a model of the knowledge base:
- 
 The interpretation with a false, and all other atoms true is not a model as the first clause is false in this interpretation. The interpretation with a false, and all other atoms true is not a model as the first clause is false in this interpretation.
- 
 The interpretation with all atoms false is not a model as the 7th clause is false in this interpretation. The interpretation with all atoms false is not a model as the 7th clause is false in this interpretation.
  
 <nowiki>(c)</nowiki> Give two atoms that are logical consequences of the KB: <nowiki>(c)</nowiki> Give two atoms that are logical consequences of the KB:
- 
 Any two of { a, c, e, f, g } . Any two of { a, c, e, f, g } .
  
 (d) Give two atoms that are not logical consequences of the KB: (d) Give two atoms that are not logical consequences of the KB:
- 
 Any two of { b, d, h } . Any two of { b, d, h } .
 +
 +===== 5.4 =====
 +(a)
 +<code>
 +C={}
 +C={c,e} (by 4 & 5)
 +C={c,e,b} (by 3)
 +C={c,e,b,a} (by 1)
 +C={c,e,b,a,j} (by 9)
 +</code>
 +
 +(b) each of {c,e,b,a,j} is true and the other atoms (including f) are false.
 +
 +<nowiki>(c)</nowiki> The rightmost branch is the top-down derivation:
 +<code>
 +   {yes⇽a}
 +       |
 +   {yes⇽b,c}
 +        / \
 +{yes⇽d,c} {yes⇽e,c}
 +    |         |
 +{yes⇽h,c} {yes⇽c}
 +              |
 +          {yes⇽}
 +</code>
teaching/is/prop-rules-solutions.1590072835.txt.gz · Last modified: 2020/05/21 16:53 by Franconi Enrico