Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Three sample data sets for variable x are given as follow. Data set A: 19, 35, 3

ID: 3131250 • Letter: T

Question

Three sample data sets for variable x are given as follow. Data set A: 19, 35, 35,41,43, 58, 60, 64, 77, 81, 92 Find the mean, mode, standard deviation, 85th percentile, five number summary and interquartile range for Data set A. If Data sets A, B and C are mixed. Find the combined mean and standard deviation. Suppose each data in Data set C is increased by 10%, find the new mean and variance. Suppose we find the corresponding data for variable y is 83532, calculate the sample covariance and correlation for variable x and y. Calculate and comment on the coefficient of determination.

Explanation / Answer

a) Ascending Order ... 19 35 35 41 43 58 60 64 77 81 92

Min 19

Q1   35

Median 58

Q2   77

Max 92

------------------------------

b) Combined sum = 605+513+649 = 1747

Combined n = 31

Hence mean combined = 1767/31 = 57

----------------------

Combined sum of X^2 = 32553+503^2 +59^2+461.818+55^2 (Using the formula X^2 = Var +Mean^2)

292529.8

Var(X) =

= 289380.8

Std dev = 537.848

-------------------------

Variance will not change

But total will be 649(1.1)= 713.9 for C

Combined total = 1767+64.9

Hence combined mean = 1831.9/31 = 59.094

D) Cov (xy) = E(XY)-E(X)E(Y)

83532/31-(1426)(1747)/31^2

=102.2581

-----------------------------------

Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
Chat Now And Get Quote