Empirical Frameworks for Deflation Analysis

Write a Python script to download post-WWII US CPI data, then programmatically identify and plot periods of deflation and disinflation.

Critically evaluate the construction and limitations of common price indices (e.g., CPI, GDP deflator) and the impact of measurement biases on identifying deflation.

Empirically test the stability of the velocity of money (V) in the Quantity Theory of Money (MV=PY) using data from a major deflationary period.

Calculate and analyze the behavior of ex-post real interest rates during a deflationary period using the Fisher Equation and historical data.

Formulate empirical criteria for identifying a liquidity trap based on the IS-LM framework, focusing on the zero lower bound and interest elasticity of money demand.