Studies on the influencing factors and prediction of product star change in the process of e-commerce transaction based on BP neural network and VAR models

Based on the data of reviews and scores of pacifiers sold in Amazon online market from February 2011 to August 2015, this paper extracts the text emotion words and the deviation degree of text content from the theme through the LDA theme model, and then combines the text length, based on VAR model to analyze the impact of the overall star level volatility of the market by comment length, text emotional words and topic deviation. Further, this study compare the prediction of star level by VAR model and BP neural network model, and finally put forward a more stable prediction model.