Research Article

An Empirical Study on Response to Online Customer Reviews and E-Commerce Sales: From the Mobile Information System Perspective

Table 5

Results of robustness test (sales volume of next month as DV).

SYS-GMM modelFixed effect of panel data
Model 1Model 2Model 3Model 4

Ratio of response to negative review0.519 (0.172)0.419 (0.068)0.434 (0.077)0.305 (0.058)
Ratio of response to positive review0.110 (0.036)0.097 (0.020)0.087 (0.022)0.050 (0.009)
Wald test value ( value)4.40 (0.000)4.15 (0.000)3.98 (0.000)3.60 (0.000)
Ratio of response to negative review × product price0.064 (0.020)0.047 (0.022)
Ratio of response to positive review × product price0.265 (0.086)0.210 (0.036)
Ratio of response to negative review × product heterogeneity0.077 (0.019)0.125 (0.049)
Ratio of response to positive review × product heterogeneity0.105 (0.047)0.129 (0.015)
Other control variableIncludedIncludedIncludedIncluded
Wald chi25,025.768,646.88
Sargan test ( value)27.503 (0.916)26.386 (0.939)
AR2 ( value)1.228 (0.219)1.311 (0.190)
R20.2270.251
F value215.91186.10
Number of observed values17800178001780017800

Note. The dependent variable is the sales volume of next month. “” and “” in the table mean that z-statistics are significant at the levels of 5% and 1%.