(* Exam Score on Study Time *)



colname={time,score};

gradedata = {{0.5, 40}, {0.5, 50}, {1, 75}, {1, 80}, {1.5, 80}, {1.5, 95}, {2,

         100}, {2, 90}, {2.5, 114}, {2.5, 103}, {2.5, 101}, {3, 116}, {3, 

        120}, {3.5, 123}, {4, 138}, {4, 133}, {4.5, 146}, {5, 152}, {5, 

        147}, {5.5, 157}, {5.5, 164}, {6, 167}, {6, 162}, {6.5, 164}, {7, 

        173}, {7, 179}, {8, 186}, {8, 193}, {9, 190}, {9, 180}};