Width prediction method of finished rolled material, width control method of finished rolled material, manufacturing method of hot-rolled steel sheet, and generation method of width prediction model of finished rolled material

A generation method of a width prediction model of a finished rolled material, the generation method generating a width prediction model of predicting a width of the finished rolled material in a hot rolling line including a heating furnace configured to heat a slab, a rough rolling mill configured to manufacture a rough rolled material by performing rough rolling on the heated slab, and a finish rolling mill configured to manufacture the finished rolled material by performing finish rolling on the rough rolled material, the generation method comprising:

• a learning data acquisition step of acquiring a plurality of pieces of learning data including performance data of a set value or an actual measurement value of a width of the rough rolled material, one or more pieces of operational performance data selected from operational performance data of the finish rolling mill, and performance data of the width of the finished rolled material;
• and
• a step of generating the width prediction model using a Gaussian process regression method in which the performance data of the set value or the actual measurement value of the width of the rough rolled material and the one or more pieces of operational performance data selected from the operational performance data of the finish rolling mill are included as input performance data and statistical information of the width of the finished rolled material is output data, using the plurality of pieces of learning data acquired in the learning data acquisition step.