The higher the value, the more likely a new word will be treated as if it had previously appeared in spam e-mail messages. The lower the value, the more likely a new word will be treated as if it had previously appeared in non-spam e-mail. For example, if you enter 0, every new word will be treated as if it were non-spam. If you enter 100%, every word will be identified as spam.
It is recommended that this value not be set higher than 40%, in order to bias the statistical analysis in favor of being non-spam thereby reducing the likelihood of a false positive.