The paper deals with interpersonal trust modelling. Terms as trust, trust values, trust affecting factors, and representation of interpersonal trust and its implementation are presented. The proposed trust model tries to integrate more factors, which affect trust for trust determination, than usual. The model covers basic factors as reciprocal trust, initial trust, subject reputation, number of subject recommendations, number of mutual contacts, and trusting disposition. The significance of these factors participating in trust forming is discussed. Modifications of parameter values describing mentioned factors and their effects on interpersonal trust evolution are investigated. The interpersonal trust model behaviour is examined by a number of parameter studies. Only some of these studies are presented in this paper and the significant results acquired from them are shown in the graphs.