Keywords:
				
				
																		Hyperplane arrangements, 													Shi threshold arrangement, 													Finite field method															
			
			
										
					
Abstract
					Richard Stanley suggested the problem of finding the number of regions and the characteristic polynomial of a certain hyperplane arrangement defined by $x_i + x_j=0,1$, which is called the Shi threshold arrangement. We present the answer of the problem, using the finite field method.