Pengaruh peran guru dan sosialisasi peer group terhadap kecenderungan sikap menyontek siswa : sebuah studi perbandingan antara SMA Negeri "X" dan SMA Swasta Keagamaan 'Y" Provinsi Sumatera Utara = The effect of teacher's roles and peer group sosialization toward the student cheating attitude : a comparative study between "X" Public High School and "Y" Religious Private High School Province of North Sumatera (Fakultas Ilmu Sosial dan Ilmu Politik Universitas Indonesia, 2012)