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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. | ||
- | < | + | < |
< | < | ||
wet floor <- wet sink & plugged sink. | wet floor <- wet sink & plugged sink. | ||
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===== 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: | ||
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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: | ||
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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. | ||
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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. | ||
< | < | ||
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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: | ||
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Any two of { b, d, h } . | Any two of { b, d, h } . | ||
+ | |||
+ | ===== 5.4 ===== | ||
+ | (a) | ||
+ | < | ||
+ | C={} | ||
+ | C={c,e} (by 4 & 5) | ||
+ | C={c,e,b} (by 3) | ||
+ | C={c,e,b,a} (by 1) | ||
+ | C={c, | ||
+ | </ | ||
+ | |||
+ | (b) each of {c,e,b,a,j} is true and the other atoms (including f) are false. | ||
+ | |||
+ | < | ||
+ | < | ||
+ | | ||
+ | | | ||
+ | | ||
+ | / \ | ||
+ | {yes⇽d,c} {yes⇽e,c} | ||
+ | | | | ||
+ | {yes⇽h,c} {yes⇽c} | ||
+ | | | ||
+ | {yes⇽} | ||
+ | </ |