The following data are measures of triceps skinfold thickness (X1), thigh circumference (X2), and midarm circumference (X3).  These three variables are used to predict percentage of body fat (Y). You can also find the data on beachboard (titled "bodyfat").

Subject        X1        X2        X3        Y

     1         19.5      43.1      29.1      11.9

     2         24.7      49.8      28.2      22.8

     3         30.7      51.9      37.0      18.7

     4         29.8      54.3      31.1      20.1

     5         19.1      42.2      30.9      12.9

     6         25.6      53.9      23.7      21.7

     7         31.4      58.5      27.6      27.1

     8         27.9      52.1      30.6      25.4

     9         22.1      49.9      23.2      21.3

    10         25.5      53.5      24.8      19.3

    11         31.1      56.6      30.0      25.4

    12         30.4      56.7      28.3      27.2

    13         18.7      46.5      23.0      11.7

    14         19.7      44.2      28.6      17.8

    15         14.6      42.7      21.3      12.8

    16         29.5      54.4      30.1      23.9

    17         27.7      55.3      25.7      22.6

    18         30.2      58.6      24.6      25.4

    19         22.7      48.2      27.1      14.8

    20         25.2      51.0      27.5      21.1

(a)  Compute the regression of Y on X1. 

(b)  Compute the regression of Y on X2.

(c)  Compute the regression of Y on X1, X2

(d)  Compute the regression of Y on X1, X2, X3

In each case, report the results in a brief APA results-style paragraph. For each individual predictor remember to report bs, standard error of each b (or confidence intervals), t-test; and for each overall model report F-test,df, and R².

(e) Compute the correlation matrix of the predictors (X1-X3)

(f) Compute the tolerance (or VIF) of each predictor for the equation (d) which includes all 3 predictors.

(g) Examine the outlier statistics for the X-space, Y-space, and influence (including DFBETAS for each predictor).  Identify the highly discrepant observations, if any.

(h) Comment on what you have learned about this data set, particularly with regard to the three predictors, and interpret the results.

Posted Date: 3/1/2013 4:39:58 AM | Location : United States

Ask an Expert

Related Discussions:- Compute the correlation matrix of the predictors , Assignment Help, Ask Question on Compute the correlation matrix of the predictors , Get Answer, Expert's Help, Compute the correlation matrix of the predictors Discussions

Write discussion on Compute the correlation matrix of the predictors
Your posts are moderated

Write your message here..

Related Questions

How is a wave front dissimilar from a ray, How is a wave front dissimilar f... How is a wave front dissimilar from a ray ? Draw the geometrical, shape of the wave fronts when (i) light diverges from a point source, and (ii) light emerges out of a convex le

Illustrate how temperature measured in fiber optic sensor, Illustrate how t... Illustrate how temperature measured in fiber optic sensor. Temperature can be measured via using a fiber which has evanescent loss which varies along with temperature. In the f

Evaluate types of charge, Questions: A neutral hollow metal ball is on ... Questions: A neutral hollow metal ball is on the end of a glass rod consequently that one can move it around easily without touching the ball. A rubber rod is chafed with rabbi

Angular and tangential acceleration, 1. Consider the centripetal accelerati... 1. Consider the centripetal acceleration due to the earth's spin for a CWRU student sitting in Strosacker auditorium. [The radius of the earth is R = 6378.1 km, Cleveland's lati

A longitudinal wave moves through a medium, As a longitudinal wave moves th... As a longitudinal wave moves through a medium, the particles of the medium: a) vibrate in a path parallel to the path of the wave b) vibrate in a path perpendicular to the p

With what initial velocity were the keys thrown, A student throws a set of ... A student throws a set of keys vertically upward to his fraternity brother, who is in a window 4.40 m above. The brother's outstretched hand catches the keys 1.30 s later. (a) W

What do you mean by magnetic induction? , Q) What do u mean by magnetic ind... Q) What do u mean by magnetic induction? what is the dimensioin of magnetic induction? Ans) Electromagnetic induction is the manufacture of a potential difference (voltage) acro

Screw gauge, i want to do experiment online i want to do experiment online

Explain angles of incidence, A light ray is reflected off a plane mirror at... A light ray is reflected off a plane mirror at an angle of 25° from the normal. A light ray from another source is reflected 54° from the normal. What is the dissimilarity i

Which ship gets hit ?rst, A battleship concurrently ?res two shells at enem... A battleship concurrently ?res two shells at enemy ships along the trajectories shown. One ship (A) is close by; the other ship (B) is far away. Which ship gets hit ?rst?