We propose an adaptive approach in agent-based negotiation involving on-line prediction of the opponent behaviour based on the parametric non-linear regression analysis. The predictive decision-making mechanism for the negotiation agent is based on the history of offers in the current negotiation encounter. In comparison to the related work the proposed approach allows the negotiation agents to predict more complex behaviour of the negotiation opponent in terms of mixture of its time-dependant and behaviour-dependant tactics. We perform experiments in order to validate the proposed approach. The results show that the predictive decision-making gives better results in terms of the utility gains for the adaptive negotiation agent as compared with a range of non-predictive negotiation strategies.