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Spurious regression. The stock market and daily temperature S&P 500 daily closing value and daily maximum temperature in New York, Sep 1 to Dec 31 2008. negative trend in both stochastic trend in S&P500 deterministic trend in temp. Spurious: ln(SP) and ln(Temperature).
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Spurious regression The stock market and daily temperature S&P 500 daily closing value and daily maximum temperature in New York, Sep 1 to Dec 31 2008 • negative trend in both stochastic trend in S&P500 deterministic trend in temp.
Spurious: ln(SP) and ln(Temperature) Spurious regression: ln(SPt) = α + βln(temperaturet) + ut Another spurious regression would be: SPt = α + βtemperaturet + ut
Correct: Δln(SP) and Δln(Temperature) Spurious regression: Δln(SPt) = α + βΔln(temperaturet) + Δut
Spurious: two simulated RW series Xt = Xt-1 + ωtωt~WN Yt = Yt-1 + εt εt~WN ωtand εt independent Spurious regression: Yt = α + βXt + ut Correct regression: ΔYt = α + βΔXt + vt