st: Interpret Ln transormed in logit regression

["Supnithadnaporn, Anupit" <gtg065t@mail.gatech.edu>]

Dear all,

Would anybody please confirm or correct my understanding about the interpretation of these coefficients? Any reference would be appreciated.

Y = Pr(vehicle fail the inspection); coded 1 if fail and 0 if pass
X = ln(income)
Z = other control variables

logit(Y) = a + b_1*X + b_i*Z

Are all of these correct?
b_1 = elasticity = increase income will decrease the odds of Y by b_1
e^b_1 = odds ratio (OR) = odds of Y increase by a factor of [e^b_1] for every unit of ln(income)
(OR-1)*100 = percentage change in odds of Y per unit change of ln(income)

Thank you
Anupit


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