9. An apparatus for discriminating among a first alphabetic form and a second alphabetic form and the numeric form of an alpha-numeric character field scanned by a character recognition machine, comprising: a character recognition machine adapted to scan the characters in a character field, to output on a first output line the alphabetic character of the aforesaid first alphabetic form which most nearly matches each character scaned, as of the aforesaid first alphabetic form for all characters scanned in said character field, to output on a second output line the alphabetic character of the aforesaid second alphabetic form which most nearly matches each character scanned, as of the aforesaid second alphabetic form for all characters scanned in said character field, and to output on a third output line a numeric character which most nearly matches each character scanned, as of a numeric form for all characters scanned in said character field; a storage means connected to said output lines, having stored therein a first type of conditional probability that a certain alphabetic character of the aforesaid first alphabetic form was inferred by the character recognition machine given that a certain alphabetic character of the aforesaid second alphabetic form and a certain numeric character were each scanned, for combinations of alphabetic characters with numeric characters, said storage means being sequentially accessed by corresponding character trios in said alphabetic and numeric fields on said output lines to yield the first type conditional probability that an alphabetic character of the aforesaid second alphabetic form on the second output line and that a numeric character on the third output line were each misread by the character recognition machine as the corresponding alphabetic character on the first output line; said storage means having stored therein a second type of conditional probability that a certain alphabetic character of the aforesaid second alphabetic form was inferred by the character recognition machine given that a certain alphabetic character of the aforesaid first character form and a certain numeric character were each scanned, for combinations of alphabetic characters with numeric characters, said storage means being sequentially accessed by corresponding character trios in said alphabetic and numeric fields on said output lines to yield the second type conditional probability that an alphabetic character of the aforesaid first alphabetic form on the first output line and that a numeric character on the third output line were each misread by the character recognition machine as the corresponding alphabetic character on the second output line; said storage means having stored therein a third type of conditional probability that a certain numeric character was inferred by the character recognition machine given that a certain alphabetic character of the aforesaid first form and that a certain alphabetic character of the aforesaid second alphabetic form were each scanned, for combinations of alphabetic characters with numeric characters, said storage means being sequentially accessed by correponding character trios in said alphabetic and numeric fields on said output lines to yield the third type conditional probability that the alphabetic characters on the first and second output lines were each misread by the character recognition machine as the corresponding numeric character on the third output line; a multiplier means having an input connected to said storage means for calculating a first product of all the first type conditional probabilities accessed from said storage means for said character field, said first product being a first total conditional probability that all alphabetic characters of the aforesaid second alphabetic form outputted on said second output line and that all numeric characters outputted on said third output line were each misread by the character recognition machine, for calculating a second product of all the second type conditional probabilities accessed from said storage means for said character field, said second product being a second total conditional probability that all alphabetic characters in the aforesaid first alphabetic form outputted on said first output line and that all numeric characters outputted on said third output line were each misread by the character recognition machine, and for calculating a third product of all the third type conditional probabilities accessed from said storage means, said third product being a third total conditional probability that the alphabetic characters outputted on said first and second output lines were each misread by the character recognition machine; a comparator connected to said multiplier means for comparing the magnitudes of said first, second and third total conditional probabilities and outputting an indication that the scanned character field is alphabetic of the aforesaid first alphabetic form when said first total conditional probability is greater than said second or third total conditional probabilities, and is alphabetic of the aforesaid second alphabetic form when said second total conditional probability is greater than said first or third total conditional probabilities, and is numeric when said third total conditional probability is greater than said first or second total conditional probabilities.
9. An apparatus for discriminating among a first alphabetic form and a second alphabetic form and the numeric form of an alpha-numeric character field scanned by a character recognition machine, comprising: a character recognition machine adapted to scan the characters in a character field, to output on a first output line the alphabetic character of the aforesaid first alphabetic form which most nearly matches each character scaned, as of the aforesaid first alphabetic form for all characters scanned in said character field, to output on a second output line the alphabetic character of the aforesaid second alphabetic form which most nearly matches each character scanned, as of the aforesaid second alphabetic form for all characters scanned in said character field, and to output on a third output line a numeric character which most nearly matches each character scanned, as of a numeric form for all characters scanned in said character field; a storage means connected to said output lines, having stored therein a first type of conditional probability that a certain alphabetic character of the aforesaid first alphabetic form was inferred by the character recognition machine given that a certain alphabetic character of the aforesaid second alphabetic form and a certain numeric character were each scanned, for combinations of alphabetic characters with numeric characters, said storage means being sequentially accessed by corresponding character trios in said alphabetic and numeric fields on said output lines to yield the first type conditional probability that an alphabetic character of the aforesaid second alphabetic form on the second output line and that a numeric character on the third output line were each misread by the character recognition machine as the corresponding alphabetic character on the first output line; said storage means having stored therein a second type of conditional probability that a certain alphabetic character of the aforesaid second alphabetic form was inferred by the character recognition machine given that a certain alphabetic character of the aforesaid first character form and a certain numeric character were each scanned, for combinations of alphabetic characters with numeric characters, said storage means being sequentially accessed by corresponding character trios in said alphabetic and numeric fields on said output lines to yield the second type conditional probability that an alphabetic character of the aforesaid first alphabetic form on the first output line and that a numeric character on the third output line were each misread by the character recognition machine as the corresponding alphabetic character on the second output line; said storage means having stored therein a third type of conditional probability that a certain numeric character was inferred by the character recognition machine given that a certain alphabetic character of the aforesaid first form and that a certain alphabetic character of the aforesaid second alphabetic form were each scanned, for combinations of alphabetic characters with numeric characters, said storage means being sequentially accessed by correponding character trios in said alphabetic and numeric fields on said output lines to yield the third type conditional probability that the alphabetic characters on the first and second output lines were each misread by the character recognition machine as the corresponding numeric character on the third output line; a multiplier means having an input connected to said storage means for calculating a first product of all the first type conditional probabilities accessed from said storage means for said character field, said first product being a first total conditional probability that all alphabetic characters of the aforesaid second alphabetic form outputted on said second output line and that all numeric characters outputted on said third output line were each misread by the character recognition machine, for calculating a second product of all the second type conditional probabilities accessed from said storage means for said character field, said second product being a second total conditional probability that all alphabetic characters in the aforesaid first alphabetic form outputted on said first output line and that all numeric characters outputted on said third output line were each misread by the character recognition machine, and for calculating a third product of all the third type conditional probabilities accessed from said storage means, said third product being a third total conditional probability that the alphabetic characters outputted on said first and second output lines were each misread by the character recognition machine; a comparator connected to said multiplier means for comparing the magnitudes of said first, second and third total conditional probabilities and outputting an indication that the scanned character field is alphabetic of the aforesaid first alphabetic form when said first total conditional probability is greater than said second or third total conditional probabilities, and is alphabetic of the aforesaid second alphabetic form when said second total conditional probability is greater than said first or third total conditional probabilities, and is numeric when said third total conditional probability is greater than said first or second total conditional probabilities. 10. The apparatus of claim 9 which further comprises: a gating means having data inputs connected to said output lines, a control input connected to the output of said comparator and an output connected to a fourth output line for selectively transmitting to said fourth output line the alphabetic field of the aforesaid first alphabetic form outputted on said first output line when said comparator indicates the character field to be of the aforesaid first alphabetic form, for selectively transmitting to said fourth output line the alphabetic field of the aforesaid second alphabetic form outputted on said second output line when said comparator indicates the character field to be of the aforesaid second alphabetic form, and for selectively transmitting to said fourth output line the numeric field outputted on said third output line when said comparator indicates said scanned character field is numeric.