# Errata

These are the known errors in the first printing of Artificial Intelligence: Foundations of Computational Agents, Cambridge University Press, 2010

No known errors.

No known errors.

## Chapter 3

Section 3.5.1 (page 81, bottom) "for some index i < n" should be "for some index i < k".

Section 3.7.3 (page 98, top). "There is a constant overhead of (b/(b-1))2 times the cost of generating the nodes at depth n. When b=2 there is an overhead factor of 4, and when b=3 there is an overhead of 2.25 over generating the frontier." should be "As there are (b/(b-1)) bk nodes in the tree, there is a constant overhead of (b/(b-1)) times the cost of generating the nodes at depth n. When b=2 there is an overhead factor of 2, and when b=3 there is an overhead of 1.5 over generating the frontier."

## Chapter 4

Figure 4.3, page 122, line 13 should not be indented (it should align with "for each")

Page 122, line 8 of text, "Although the set..." should be "While the set...".

## Chapter 5

Figure 5.4 (p173), line 3, "KB: a set definite clauses" should be "KB: a set of definite clauses"

In Example 5.22 (page 191), all of the tuples that contain connected_to should be removed.

Section 5.6, last sentence (page 206), "that are not subsets of conflicts" should be "such that no subset is a conflict". (Thanks to Michael Bartholomew for finding this.)

Section 5.7 (page 206) "clausal mechanism" should be "causal mechanism".

Section 5.7 (page 206), before point 1, "An observation can implemented..." should be "An observation can be implemented..."

## Chapter 6

On pages 242, 243, the text in Example 6.13, from "This network can be used ..." to the end of the example should be at the end of Example 6.12.

In Figure 6.8 (page 254), line 22, "Rs" should be "Fs". On lines 18, 20, 21, and 23 ":=" should be "←"

Example 6.26 (page 263), q(Alarm | Tampering, Alarm) = P(Alarm | Tampering, Alarm) should be q(Alarm | Tampering, Fire) = P(Alarm | Tampering, Fire).

## Chapter 7

Section 7.2.1, page 293 "fp is the number of false negatives" should be "fp is the number of false positives".

Figure 7.12 (p. 318) lines 23 and 25, should include sigmoid(.). They should read:
23:                      hid[h]  :=  sigmoid(∑i=0n hw[i,h] ×val(e,Xi))
25:                       out[o]  :=  sigmoid (∑h=0n hw[i,h] ×hid[h])
Line 34 should be return hw,ow

## Chapter 8

In Example 8.1 (page 351), "Rob can deliver coffee....make RHC true...", should be "...make RHC false".

Section 8.1.4, page 355, "The are two sorts of goals:" should be "There are two sorts of goals:".

In Example 8.2, (page 352) "Sam has mail" should be "Rob has mail".

## Chapter 9

Figure 9.11 (page 393), line 3, "a single stage decision network" should be "a decision network".

Figure 9.11 (p. 393) line 13 should be "Sum out each random variable that is not a parent of a decision node".

Example 9.18 (p. 394). "VE_DN sums out the random variables that are not ancestors of a decision node" should be "VE_DN sums out the random variables that are not parents of a decision node".

In Section 9.3.3, 3rd paragraph, (page 393), "there must be one decision variable that is in a factor with some subset of its parents" should read "there must be one decision variable that is in a factor that only contains it and some subset of its parents".

No known errors.

## Chapter 11

Fischer (1987) should be Fisher (1987).

No known errors.

## Chapter 13

Figure 13.6 (page 570). The last two lines should read:
owl:TransitiveObjectProperty(P) if xPy and yPz then xPz
owl:SymmetricObjectProperty(P) if xPy then yPx

## Chapter 14

Example 14.18 (page 614). "person P" should be "problem P" (2 occurrences in first paragraph)

Box on page 619. First paragraph "friends" should be "likes". "students" should be "student's".

No known errors.

No known errors.

## References

Fischer, D. (1987) should be Fisher, D. (1987).

## Index

Page 658. "minimal" should not have subitems but should be:
minimal conflict, 187
minimal model, 169, 509

Page 658:
"M features, 360" should be "state features, 360"
"M system, 51" should be "hybrid system, 51"