Quantitative Economic Modeling in Python

    # == Test that nu has a real solution before assigning == #
    warning_msg = """
    Hint: you probably set government spending too {}.  Elect a {}
    Congress and start over.
    """
    disc = a0**2 - 4 * a0 * b0
    if disc >= 0:  
        nu = 0.5 * (a0 - sqrt(disc)) / a0
    else:
        print "There is no Ramsey equilibrium for these parameters."
        print warning_msg.format('high', 'Republican')
        sys.exit(0)

    # == Test that the Lagrange multiplier has the right sign == #
    if nu * (0.5 - nu) < 0:  
        print "Negative multiplier on the government budget constraint."
        print warning_msg.format('low', 'Democratic')
        sys.exit(0)

Fellow laureate Krugman: "S and S played a key role in developing methods that let the data speak instead": http://krugman.blogs.nytimes.com/2011/10/10/go-princeton-and...

The models here however aren't econometric, they are for theoretical economics. The Kalman filter can be used for 10001 different things.

For instance, here's how many times the following words appear in it:

   Money        : 0 mentions
   Incentive(s) : 1 mention
   Market(s)    : 0 mentions

(I'm not saying it ISN'T an economics text... I'm just hoping someone can genuinely answer my newbie question :-)