1. A speaker independent apparatus for word recognition comprising: a) input means for inputting an utterance by an unspecified person into an electrical signal; b) characteristic extracting means for receiving the electrical signal from the input means and converting the electrical signal into a time series of discrete characteristic multidimensional vectors; c) phoneme recognition means for selectively receiving the time series of discrete characteristic multidimensional vectors and converting each of said selectively received vectors into a plurality of candidates of phonemes from a first order to an n-th order (n denotes an arbitrary number); d) word recognition means for receiving a time series string of phonemes from the phoneme recognition means and comparing the plurality of candidates of phonemes, one at a time, with each phoneme of a reference string of phonemes for words previously stored in a dictionary until a final phoneme of the reference string of phonemes for a last word of the words stored in the dictionary and determining a time series of phonemes derived from said phoneme recognition means having a highest similarity to one of the reference strings of the phonemes for the words stored in the dictionary using a predetermined word matching technique; e) output means for outputting at least one of said candidates of phonemes as a result of word recognition carried out by the word recognition means on the basis of a similarity determination on the plurality of candidates of phonemes with respect to the reference strings of the words stored in said dictionary; and f) selecting means, interposed between said characteristic extracting means and phoneme recognition means, for selecting a center of a given number of frames of a continued time-series of discrete characteristic multidimensional vectors derived from said characteristic extracting means so that said phoneme recognition means receives the center thereof.
2. An apparatus as set forth in claim 1, wherein said word recognition means for determining the time series of strings of phonemes derived from said phoneme recognition means has a totally similarity to the time series reference string of phonemes for each word depending upon a distance from one of the plurality of candidates of the phonemes to one of the phonemes of the reference string of the phonemes in a two-dimensional coordinate matrix and wherein said output means outputs a plurality of word candidates as the result of word recognition according to a derived distance, a first order of the plurality of word candidates being the word having the reference string of phonemes with a smallest distance to the candidates of the time series of phonemes derived from said phoneme recognition means.