Consideration of cross-validation in estimating objective scores of answer statements posted at Q&A sites

To eliminate mismatches between the intentions of questioners and respondents of Question and Answer (Q&A) sites, we have clarified that the impression of the statements could be captured by nine factors, and the factor scores could be estimated from the feature values of the statements. Objective scores of the statements could be estimated fairly good, and that those of subjective statements could be estimated well by taking the natural logarithm of the factor scores. This result, however, is likely to estimate inaccurate values due to overfitting to the explanatory variables. This could result from not having considering cross-validation through the attempts. This paper tries to perform multiple regression analysis with the consideration of cross-validation. For statements of Yahoo! Auction, PC and love counseling & human relationships, respective five trials have been attempted. As a result, most of the attempts show good or fairly good estimation accuracy. It is suggested that estimation errors should be reduced.