## An Errata for Martin Peterson, An Introduction to Decision Theory, Cambridge University Press, 2009

- Page 26. Last paragraph line 3. Exchange
**G = 10 · H + 10**for**H = 10 · G + 10**. - Page 27. Line 5. The constant
*m*can be positive or negative. - Page 30. Lines 7–8.
*a*_{2}should be deleted from all three sets. - Page 39. Solution to exercise 2.11. Exchange
**(5)**for**(4)**throughout. - Page 42. In the definitions of Weak and Strong Dominance, exchange
**if and only if**for**if**. - Page 51. The definition of Minimax regret should read:
*a*_{1}≻*a*_{2}if and only if min{(*v*(*a*_{1},*s*_{1}) − max(*s*_{1})), (*v*(*a*_{1},*s*_{2}) − max(*s*_{2})), …} > min{(*v*(*a*_{2},*s*_{1}) − max(*s*_{1})), (*v*(*a*_{2},*s*_{2}) − max(*s*_{2})), …}

- Page 59. In row 4 (continuity) last column (insufficient reason) exchange
**⊗**for**×**. - Page 62. The solution to 3.5. In the top row of the last column exchange
**1**for**0**. - Page 82. The equations before the last paragraph should be:
- eu(G1) − eu(G2) = (30/90)M − (B/90)M = (30 − B)M/90
- eu(G3) − eu(G4) = ((30 + 60 − B)/90)M − (60/90)M = (30 − B)M/90

- Page 85. In the definition of Gamble 1 exchange
**min**for**max**. - Page 104. Equation (i). Exchange
**Ford**for**Jaguar**and**Jaguar**for**Ford**. - Page 105. Last line. The utility of the Saab should be 0.55 + 0.36 = 0.91.
- Page 115. Solution to 5.6. Line 2 should read “…
*x*≻*y*implies that*x*≻*z*or*z*≻*y*. The second possibility,*z*≻*y*, is inconsistent with what we initially supposed”. In the solution to 5.7 all that can be concluded is that 0.9B + 0.1C = 0.6B + 0.4D. - Page 128. Second paragraph line 9. Exchange
**biased**for**not biased**. - Page 132. In the solution to exercise 6.6, part (a), delete
**1/6 · 1/6**(the answer, 6/36, is still correct). The solution to problem 6.7 should be 10/37 ≈ 0.27. In the solution to exercise 6.8 exchange**0.53**for**0.552**. - Page 157. In line 8, exchange
for*p*(x) > 0and in line 18,*p*(x) < 0for*p*(*x*∨ ¬*x*) > 1. In the last paragraph line 4 the last*p*(*x*∨ ¬*x*) < 1**x'**should be in italic typeface and in line 5, exchangefor*y*.*x'* - Page 168. Proof of Theorem 8.1. The third line, should read ”between
*x*and*y*at…”. - Page 168. Main text, line 1. Exchange
**regard**for*x*and*y***regard**.*x*and*z* - Page 168. Main text, line 2. Exchange
for*y*health**z health**. - Page 179. Line 5. Exchange
**xpy**for**xpz**. - Page 186. In line 2,
*x*^{-3/2}divided by*x*^{-1/2}should be*x*^{-1}, not*x*^{-3}. In line 4,*x*^{-5/3}divided by*x*^{-2/3}should be*x*^{-1}, not*x*^{-10/3}. - Page 189. The expected utility for taking boxes 1 and 2 is $11,000, not $10,000 (because
should be*u*($0)).*u*($1000) - Page 194. Second paragraph. Exchange all
**X**for**Y**and all**Y**for**X**. - Page 262. Solution to 12.8. (R2, C1) is also a Nash equilibrium.
- Page 267. Lines 2–3. Exchange
**O were to prefer**for*f*to*e***Q were to prefer**.*b*to*a* - Page 282. Exercise 13.1 line 2. Delete
**or**.*f* - Page 284. Exercise 13.5(b). The answer is correct, but
**No**should be deleted. - Page 286. Line 12. C and D have been reversed in the definition of the lotteries.
- Page 308. Entry Herodotus (1954). Exchange
**Penquin**for**Penguin**.