Q1.  Given (x1,y1), (x2,y2), ..., (xn,yn) best fitting data to y=f(x) by least squares requires minimization of

 


Q2. The following data

x

1

20

30

40

1

400

800

1300

 

is regressed with least squares regression to y=a0+a1x.  The value of a1 most nearly is

27.480

28.956

32.625

40.000

 


Q3. The following data

 

x

1

20

30

40

1

400

800

1300

 

is regressed with least squares regression to y=a1x.  The value of y=a1x most nearly is

27.480

28.956

32.625

40.000

 


Q4.  An instructor gives the same y vs x data as given below to four students and asks them to regress the data with least squares regression to y=a0+a1x.

 

1

10

20

30

40

1

100

400

600

1200

 

Each student comes up with four different answers for the straight line regression model.  Only one is correct.  The correct model is

y=60x-1200

y=30x-200

y=-139.43+29.684x

y=1+22.782x

 


Q5A torsion spring of a mousetrap is twisted through an angle of 1800.  The torque vs angle data is given below.

 

Torsion, T, N-m

0.110

0.189

0.230

0.250

Angle, θ, rad

0.10

0.50

1.1

1.5

 

The amount of strain energy stored in the mousetrap spring in Joules is

0.29872

0.41740

0.84208

1561.8

 


Q6.  A scientist finds that regressing the y vs x data given below to y=a0+a1x results in the coefficient of determination for the straight-line model, r2 being zero.

 

x

1

3

11

17

2

6

22

?

 

The missing value for y at x=17 most nearly is

-2.4444

2.0000

6.8889

34.000

 

 

 

> Home > Quizzes > Regression