The Persona Effect Of Teaching Agents: Model Construction And Empirical Testing

In order to increase the social interaction of virtual learning environment,more and more human characteristics are added into human-computer interface.Pedagogical agent is an important element in VLEs.It is a cartoon character or animated character which is designed to help the learning process in computer aided learning.Whether human people will be able to treat agents as real social actors and show social reactions to them,as well as whether agents have a social impact on human?These are questions which this study interested inThe presence of pedagogical agent can promote the functions of the conversational computer system,and then lead to lots of positive effects on learning(e.g.motivation),which is known as "persona effect".Although some meaningful results have been revealed,there are still some defects in many aspects:The theoretical explanation of persona effect is still shallow,lacking of systematic theoretical construction.The weakness of theoretical research makes it difficult to explain the existing inconsistent results,and also limits the development of empirical research.Therefore,more adequate theoretical study and empirical tests are needed.In this study,we reviewed the concept of persona effect and constructed the stage model of persona effect.Then,we explored several important research questions based on the model.The present study conducts five sub studies to explore these questions,including a theoretical study and four experiments.There were two main missions completed in the theoretical research.(1)The study deeply analyzed the definition and empirical orientation of persona effect.Based on the original concept,xwe improved and revised it in 3 aspects,then proposed a nexw concept of persona effect.(2)The study deeply analyzed and integrated the existing theoretical opinions,and then constructed a stage model of persona effect.The model systematically described and explained the necessary conditions,mechanism,influencing factors and consequences of persona effect through dividing the effect into four stages:social verification,social reaction,effect activation and effect performance.Based on the main point of the stage model,empirical study explored the persona effect in a virtual Taijiquan learning situation.Experiment 1 investigated the role of agent's visual presentation on the activation of persona effect.The experiment adopted a single factor within-subject design to examine the effect of visual presentation on perceived social presence,flow experience and learning performance.Results revealed that the visual presentation of the agent led to a higher level of social verification,and made the subjects feel that the agent has a higher sense of social presence.Furthermore,the visual presentation of the agent led to a higher level of learning motivation,flow experience and learning performance.Experiment 2 further examined the effects of agents' temperament types and feedback strategies on learning,including two pre experiments and a formal experiment.Pre experiment 1 created two agents with choleric temperament and two agents with phlegmatic temperament.Pre experiment 1 created a set of upper body gestures expressing positive feedback and another set of gestures expressing negative feedback.The manipulation test results of the two pre experiments supported the validity of these designs.The formal experiment adopted a 2(temperament types:choleric vs phlegmatic)X 2(feedback strategy:positive vs negative)two-factor mixed design to explore the effect from agent's temperament type and feedback strategy on learning related variables.Results revealed that both personality type and feedback strategy are characteristics significantly influencing learning.However,temperament type merely affected learning performance,while feedback strategy significantly affected not only learning performance,but also positive emotions,self efficiency,and flow experience.To explain these results,we further divided learning motivation into intrinsic motivation and external motivation in discussion,and then proposed an explanation model.Experiment 2 examined the explanation model proposed in experiment 2.The experiment adopted a 2(temperament types:choleric vs phlegmatic)X 2(feedback strategy:positive vs negative)two-factor within-subject design to explore the effect from agent's temperament type on external motivation related variables and effects from feedback strategy on intrinsic motivation related variables.Results supported the explanation model and suggested that agent's temperament type significantly affected threat perception and external motivation related variables through external motivation influence path.Feedback strategy significantly affected emotion valence,self-efficiency by intrinsic motivation influence path.Based on the effect mechanism of temperament type and feedback strategy,as well as the characteristics of high-shy individuals,it can be expected that shyness is a potential moderate factor of persona effect.Thus,experiment 4 tested the potential moderate effect of shyness.The experiment adopted a 2(shyness level:high vs low)×2(temperament types:choleric vs phlegmatic)X 2(feedback strategy:positive vs negative)three-factor mixed design to explore whether the effect of agent's temperament type and feedback strategy on learning could be moderated by shyness level.The participants' shyness level and agents' temperament type were between-subject factors,while the agents' feedback strategy was within-subject factor.Dependent variables were flow experience and learning performance.Results revealed that shyness level significantly moderated the persona effect.Specifically,the participants' shyness level not only moderated the effect from agents'temperament type on learning performance,but also moderated the effect from agents'feedback strategy on flow experience.For high-shy individuals,agents' temperament types and feedback strategies significantly affected learning;for low-shy individuals,agents' temperament types and feedback strategies had no significant influence on learning.Empirical results supported the main ideas of phase model,and further completed the model.Firstly,it is reasonable to put agent's characteristics in the concept of persona effect.Not only the presence of agent can lead to persona effect,but also the various characteristics can do it.These results also suggested it was necessary that the activation of persona effect w as divided into two kinds of types,i.e.specific priming and nonspecific priming.Secondly,motivation effect path is an important influence path of persona effect.All of the visual presentation,temperament types and feedback strategies of agents affected learning by motivation effect path.Thirdly,flow experience is an important result variable of persona efect.The deeper relation between persona effect and flow effect worth to futher explore.Finally,persona effect is moderated by individual difference,and shyness is an individual difference significantly moderating persona effect.