1. A method of recognizing input speech of many unspecific people, comprising the steps of: obtaining feature parameters of said input speech by: determining parameters representing a short-time average spectrum envelope characteristic of a speech signal from the input speech, and determining parameters which are regression coefficients obtained from outputs from a wide-band filter bank and which represent a rough directionality of a characteristic of a change in a spectrum of said speech signal; and determining correspondence between said combination and one of a plurality of standard patterns stored in a storage means such that a distance between said combination and said one pattern is the smallest of all said patterns so as to recognize said input speech; said step of determining said parameters which are regression coefficients, includes the steps of: filtering said speech signal in a plurality of filters having mutually overlapped frequency ranges; calculating short-time average energy values of outputs of said filters, including a short-time average energy value which represents a total energy of said speech signal over the entire frequency range; normalizing said short-time average energy values by subtracting said short-time average energy value which represents said total energy from the remaining short-time average energy values; calculating said regression coefficients from said normalized short-time average energy values.