This document last updated: 14 May 2012.
I'll list corrections to the main pdf document here and incorporate them into the pdf document from time to time.
2007 A4: (b) The second version of the answer should be the negative of what it currently is.
2008 B1: (d) I lost a division sign: stability requires mu < 2b/(1+b)
2009 A3: (b) unemployment rate after 3 periods is 11.715% (the 10% figure is the new equilibrium rate)
2009 C2: (d) should say "do not reject the null hupothesis"!
2010 C9: (a)(ii) should be 13/14, not 1/14.
2011 A2: (i) top left term in the Hessian should have the power of K as alpha-2, not alpha.
2011 B5: (ii) should be (x,y)=(10/3,10/3). You might also get (20/3,5/3), but that does not solve the first order equations unless you take the square roots that appear at various points as negative.
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