Statistics 3540
Assignment #3: Solutions
1. Refer back to the DJIA data used in Assignment #2, and answer the following:
(a) Fit the regression model
yt = 0 + 1 t + 2 t2 +
t
See output below.
The regression equation is
DJIA = 1150 - 124 Time + 9.51 Timesq
Student ID: -
PROBLEM #3: (10 Marks)
Pair of Ice Tongs is shown below. The ice cube weighs 50lb and is 10in wide across the tongs.
The distance between the handles is 4in and the mean radius r is 6in. Draw the free body diagram
and find all the forces act
Student ID: -PROBLEM #2: (5 Marks)
The piston of an IC engine is connected to its connecting rod with a writs pin. The force on the
wrist pin is 2750lb. Design the wrist pin (the internal diameter) for a maximum allowable force
of 20Ksi, if the pin is hol
Statistics 3540
Assignment #1: Solutions 30 POINTS
1. Problem on the sampling distribution of x.
NOTE: No computer output is required in the solutions. Also, not everyone will have the
same results, since the values are randomly generated.
(a) From the ou
Statistics 3540
Assignment #2: Solutions
1. Find least squares estimate of 1 in
yi = 1 x2 + ei
i
Solution: Dene SS(1 ) =
i (yi
1 x2 )2 . Then
i
dSS(1 )
= 2
d(1 )
x2 (yi
i
1 x2 )
i
x2 (yi 1 x2 ) = 0
i
i
i
= 0
i
x4 =
i
1
x2 yi
i
i
i
1 =
i
x2 yi
i
x4
i i
Te
Statistics 3540
Assignment #4: Solutions
1. Use the unemployment data from Assignment #3 to answer the following:
(a) Analyze the data by using the multiplicative decomposition method. Make sure
to comment on any features you see in the plots of (i) the d