# Impulse-response function

The impulse response function , and pulse response function ( English impulse response function ) determined in the context of time series analysis , the type and duration, in using the pulse , which at a certain time t occurs, affects subsequent time series values. The momentum-response function can be used as a lag polynomial in the rational form:

${\ displaystyle \ nu (L): = {\ frac {\ omega (L)} {\ delta (L)}} L ^ {d}}$

to be brought. The exponent d describes the delay time that elapses until the first reaction of the time series values. The degree of the polynomials and hardly goes beyond two in practical application. ${\ displaystyle Y_ {t}}$ ${\ displaystyle \ omega (L)}$${\ displaystyle \ delta (L)}$