<P> The 2010 Flash Crash incident was blamed on the practice of high - frequency trading (HFT), although whether HFT really increases systemic risk remains controversial . </P> <P> Agriculture and human population can be considered to be in a positive feedback mode, which means that one drives the other with increasing intensity . It is suggested that this positive feedback system will end sometime with a catastrophe, as modern agriculture is using up all of the easily available phosphate and is resorting to highly efficient monocultures which are more susceptible to systemic risk . </P> <P> Technological innovation and human population can be similarly considered, and this has been offered as an explanation for the apparent hyperbolic growth of the human population in the past, instead of a simpler exponential growth . It is proposed that the growth rate is accelerating because of second - order positive feedback between population and technology . Technological growth increases the carrying capacity of land for people, which leads to more population, and so more potential inventors in further technological growth . </P> <P> Gunnar Myrdal described a vicious circle of increasing inequalities, and poverty, which is known as "circular cumulative causation". </P>

What type of feedback provides a response that is opposite to the original stimulus