Abstract: Free trial is a primary and expensive method for SaaS cloud service operators to acquire users. Therefore, a key issue for decision-makers is to determine what trial strategies are most profitable in what market contexts for operators. In this study, the SaaS user experience model is proposed to describe the perceived quality distribution before and after the trial experience of SaaS users. The optimization model for the portfolio strategy of trial quality and trial duration is constructed for SaaS cloud service. The research finds that: When SaaS service market underestimates service quality and its perceived uncertainty is in a “high uncertainty” situation, SaaS operators should adopt the time-limited trial strategy of “high trial quality + low trial duration”; When the market is in the situation of “underestimation + low uncertainty”, operators should adopt the mixed trial strategy of “high trial quality + high trial duration” to reverse the market’s underestimation of service quality; When the market overestimates SaaS service quality and the quality perception is in the situation of “high uncertainty”, operators should adopt the functional-limited trial strategy of “low trial quality + high trial duration”; When the market is in the situation of “overestimation + low uncertainty”, operators should adopt the mixed trial strategy of “low trial quality + low trial duration”. This paper also analyzes the impact of SaaS operators’ learning factor on trial strategies in four market contexts.

Key words: software-as-a-service, free trial, user experience model, consumer choice behavior model, portfolio strategy