Utility Function Approach to Portfolio Selection Problem Anna Andreevna Malakhova, Elena Nikolaevna Sochneva, Svetlana Anatolyevna Yarkova, Albina Sergeevna Danilova, Elena Anatolyevna Yurieva, Alexey Yurievich Senchenko, Olga Valeryevna Starova, Dmitry Ivanovitch Kravtsov, Dmitry Valeryevitch Zyablikov Lecture Notes in Networks and Systems, 2021