Question

A certain professor teaching Statistics is interested in finding out the relationship between the age of her students and the number of hours (per week) spent by the student emailing, texting, on social media etc. The professor collected information on 5 students. The table below lists the age of the student and the number hours spent emailing, texting, on social media etc. per week. (10) Age (in years) 18 23 19 21 29 14 Number of hours spent 844048 emailing, texting, on social media etc. per week Note that x = 110, x = 2496, y = 221, y = 12381, and Xxy = 4485 (a) From the data above do you expect the age (in years) and the time spent by students emailing, texting, on social media etc. in hours per week) to be positively or negatively related? Give reasons for you answer. (b) Compute the linear correlation coefficient.

Answer 1

a) from the data we see that if age (2) increases number of house (y) tends to decrease I for age 18 y is 84 for age 19, y is 48 for age 21 y is 35 4 so on? = x 2 y would be negatively cosselated y is 35 r = sexy - (Exi) (Eyi) Inzz- (2x)+ ][ n Ey-- (2y3] 5x4485 - 110 X22) 7 (5x 2496 - 110375 x 12381 – 221) -0.846