“…Many researchers have suggested variables that predict price levels at certain periods in the STSS and tested their significance. The variables include the total shipment quantity at previous day, wholesale prices at previous day, national holiday effect, the days elapsed after shipping of newly harvested products, substitution price level, the day-of-the-week effects and so on (Kwak, et al, 2011(Kwak, et al, , 2013(Kwak, et al, , 2014. Among those agricultural product variables from prior studies, this study focuses on improving the marginal point of a price variable used in the existing STSS.…”