Assignment:  
1.  Extract the data for the four data series below into Excel.
2.  Create a table of descriptive statistics for the four data series.
3.  Create a histogram for each of the data series.  Modify the histograms
to make them look good (by changing dimensions, labels, etc., as necessary).
4.  Create a new series that is the natural log of QRAT.  You do this by 
creating a new column, and then using the formula =LN(A2), if A2 is the 
first observation of QRAT.  Then copy that formula down the entire column.  
(I'll explain what this means in class.)
5.  Create a histogram for the new series you just created.
6.  What do you observe about each data series, in terms of its symmetry
and the relationship between its mean and median?


E.B. Lindenburg and S.E. Ross, "Tobin's Q Ratio and Industrial Organization,"
Journal of Business, 54:1 (January 1981), pp 1-32.
S.M. Stigler, "Do Robust Estimators Work with Real Data?" The Annals of Statistics,
1977, pp 1055-1098.
A.J. Duncan, Quality Control and Industrial Statistics, 4th Ed., Richard D. Irwin,
1974, p. 67.
C.J. Verhoeven, Techniques in Corporate Manpower Planning, Nijhoff, 
Amsterdam, p 50.

Authorization: free use 
Description: 
Four variables have been selected which have different distribution patterns.
Number of cases: varies 
Variable Names: 
QRAT = Market value to replacement cost ratio for 50 firms out of 250 
DENS = 29 measures of the density of earth compared to water by Cavendish in 1798 (from Stigler) 
STR = Yarn strength (lbs) of 22s yarns (from A.J. Duncan) 
AGE = Age of officers attaining the rank of colonel in the Royal Netherlands Air Force (from Verhoeven) 

The Data: 
  QRAT	STR  AGE     DENS

114	66	47	550
79	117	47	561
76	132	48	488
109	111	48	507
117	107	48	526
237	85	48	555
97	89	49	536
152	79	49	529
113	91	49	558
117	97	49	565
114	138	49	557
169	103	49	553
141	111	50	562
135	86	50	529
294	78	50	544
117	96	50	534
135	93	50	579
107	101	50	510
157	102	50	527
109	110	50	539
89	95	50	542
106	96	50	547
183	88	50	563
176	122	50	534
421	115	50	546
364	92	51	530
320	137	51	575
102	91	51	568
158	84	51	585
114	96	51	*
60	97	51	*
120	100	51	*
369	105	51	*
171	104	51	*
231	137	51	*
192	80	51	*
91	104	52	*
81	104	52	*
80	106	52	*
146	84	52	*
99	92	52	*
81	86	52	*
209	104	52	*
136	132	52	*
112	94	52	*
143	99	52	*
122	102	52	*
101	101	52	*
112	104	52	*
552	107	52	*
*	99	52	*
*	85	52	*
*	95	52	*
*	89	52	*
*	102	52	*
*	100	52	*
*	98	52	*
*	97	52	*
*	104	52	*
*	114	52	*
*	111	52	*
*	98	52	*
*	99	52	*
*	102	52	*
*	91	53	*
*	95	53	*
*	111	53	*
*	104	53	*
*	97	53	*
*	98	53	*
*	102	53	*
*	109	53	*
*	88	53	*
*	91	53	*
*	103	53	*
*	94	53	*
*	105	53	*
*	103	53	*
*	96	54	*
*	100	54	*
*	101	54	*
*	98	54	*
*	97	54	*
*	97	54	*
*	101	54	*
*	102	54	*
*	98	54	*
*	94	54	*
*	100	54	*
*	98	*	*
*	99	*	*
*	92	*	*
*	102	*	*
*	87	*	*
*	99	*	*
*	62	*	*
*	92	*	*
*	100	*	*
*	96	*	*
*	98	*	*