UNIVERSITY OF CALIFORNIA, LOS ANGELES
Department of Economics

Economics 143 (Cameron) - Applied Regression Analysis

Classroom Handout #17: Heteroscedasticity Diagnostics


 |_sample 1 50
 |_* note the use of the format command:

 |_format(3x,f4.1,f6.1,f5.0,f6.0,f6.1)
 |_read(transp87.dat) taxrate price gas regist roads / format

 UNIT 88 IS NOW ASSIGNED TO: transp87.dat
  READ USES FORMAT:(3x,f4.1,f6.1,f5.0,f6.0,f6.1)

 |_* variables are defined as follows:
 |_* 50 state-level cross-sectional observations for the year 1987 on the
 |_*  variables GAS (transportation energy use in trillion BTUs), PRICE (cents
 |_*  per gallon average for all grades of fuel, excluding taxes), TAXRATE (the
 |_*  state gas tax, in cents per gallon), REGIST (the number of motor vehicle
 |_*  registrations), and ROADS (thousands of miles of public roads and
 |_*  streets).  Note presence of character data in the first three columns.
 
 |_ols gas price taxrate regist / resid=e
 
 REQUIRED MEMORY IS PAR=     6 CURRENT PAR=   500
  OLS ESTIMATION
       50 OBSERVATIONS     DEPENDENT VARIABLE = GAS
 ...NOTE..SAMPLE RANGE SET TO:      1,     50
 
  R-SQUARE =   0.9257     R-SQUARE ADJUSTED =   0.9209
 VARIANCE OF THE ESTIMATE-SIGMA**2 =   17532.
 STANDARD ERROR OF THE ESTIMATE-SIGMA =   132.41
 SUM OF SQUARED ERRORS-SSE=  0.80646E+06
 MEAN OF DEPENDENT VARIABLE =   427.00
 LOG OF THE LIKELIHOOD FUNCTION = -313.157
 
                      ANALYSIS OF VARIANCE - FROM MEAN
                       SS         DF             MS                 F
 REGRESSION       0.10055E+08      3.       0.33515E+07           191.167
 ERROR            0.80646E+06     46.        17532.               P-VALUE
 TOTAL            0.10861E+08     49.       0.22165E+06             0.000
 
 VARIABLE   ESTIMATED  STANDARD   T-RATIO        PARTIAL STANDARDIZED ELASTICITY
   NAME    COEFFICIENT   ERROR      46 DF   P-VALUE CORR. COEFFICIENT  AT MEANS
 PRICE      1.4736      4.128      0.3569     0.723 0.053     0.0158     0.2258
 TAXRATE   0.92519      6.431      0.1439     0.886 0.021     0.0066     0.0307
 REGIST    0.12291     0.5577E-02   22.04     0.000 0.956     0.9665     1.0292
 CONSTANT  -122.01      325.5     -0.3748     0.710-0.055     0.0000    -0.2857

 |_genr e2=e*e
 
 |_ols e2 price taxrate regist
 
 REQUIRED MEMORY IS PAR=     6 CURRENT PAR=   500
  OLS ESTIMATION
       50 OBSERVATIONS     DEPENDENT VARIABLE = E2
 ...NOTE..SAMPLE RANGE SET TO:      1,     50
 
  R-SQUARE =   0.2682     R-SQUARE ADJUSTED =   0.2205
 VARIANCE OF THE ESTIMATE-SIGMA**2 =  0.16523E+10
 STANDARD ERROR OF THE ESTIMATE-SIGMA =   40648.
 SUM OF SQUARED ERRORS-SSE=  0.76005E+11
 MEAN OF DEPENDENT VARIABLE =   16129.
 LOG OF THE LIKELIHOOD FUNCTION = -599.498
 
                      ANALYSIS OF VARIANCE - FROM MEAN
                       SS         DF             MS                 F
 REGRESSION       0.27859E+11      3.       0.92863E+10             5.620
 ERROR            0.76005E+11     46.       0.16523E+10           P-VALUE
 TOTAL            0.10386E+12     49.       0.21197E+10             0.002
 
 VARIABLE   ESTIMATED  STANDARD   T-RATIO        PARTIAL STANDARDIZED ELASTICITY
   NAME    COEFFICIENT   ERROR      46 DF   P-VALUE CORR. COEFFICIENT  AT MEANS
 PRICE     -269.10      1267.     -0.2123     0.833-0.031    -0.0296    -1.0918
 TAXRATE    1209.3      1974.      0.6125     0.543 0.090     0.0881     1.0613
 REGIST     6.5838      1.712       3.845     0.000 0.493     0.5294     1.4595
 CONSTANT  -6920.7     0.9993E+05 -0.6926E-01 0.945-0.010     0.0000    -0.4291

 |_sort regist gas price taxrate
 DATA HAS BEEN SORTED BY VARIABLE REGIST
 
 |_ols gas price taxrate regist
 
 REQUIRED MEMORY IS PAR=     6 CURRENT PAR=   500
  OLS ESTIMATION
       50 OBSERVATIONS     DEPENDENT VARIABLE = GAS
 ...NOTE..SAMPLE RANGE SET TO:      1,     50
 
  R-SQUARE =   0.9257     R-SQUARE ADJUSTED =   0.9209
 VARIANCE OF THE ESTIMATE-SIGMA**2 =   17532.
 STANDARD ERROR OF THE ESTIMATE-SIGMA =   132.41
 SUM OF SQUARED ERRORS-SSE=  0.80646E+06
 MEAN OF DEPENDENT VARIABLE =   427.00
 LOG OF THE LIKELIHOOD FUNCTION = -313.157
 
                      ANALYSIS OF VARIANCE - FROM MEAN
                       SS         DF             MS                 F
 REGRESSION       0.10055E+08      3.       0.33515E+07           191.167
 ERROR            0.80646E+06     46.        17532.               P-VALUE
 TOTAL            0.10861E+08     49.       0.22165E+06             0.000
 
 VARIABLE   ESTIMATED  STANDARD   T-RATIO        PARTIAL STANDARDIZED ELASTICITY
   NAME    COEFFICIENT   ERROR      46 DF   P-VALUE CORR. COEFFICIENT  AT MEANS
 PRICE      1.4736      4.128      0.3569     0.723 0.053     0.0158     0.2258
 TAXRATE   0.92519      6.431      0.1439     0.886 0.021     0.0066     0.0307
 REGIST    0.12291     0.5577E-02   22.04     0.000 0.956     0.9665     1.0292
 CONSTANT  -122.01      325.5     -0.3748     0.710-0.055     0.0000    -0.2857

 |_diagnos / het chowtest
 
 REQUIRED MEMORY IS PAR=     9 CURRENT PAR=   500
 DEPENDENT VARIABLE = GAS             50 OBSERVATIONS
 REGRESSION COEFFICIENTS
    1.47359007578      0.925194440215      0.122914149650      -122.005381949
 
 
 HETEROSKEDASTICITY TESTS
                             CHI-SQUARE     D.F.   P-VALUE
                           TEST STATISTIC
 E**2 ON YHAT:                     12.894     1    0.00033
 E**2 ON YHAT**2:                   7.356     1    0.00669
 E**2 ON LOG(YHAT**2):              9.210     1    0.00241
 E**2 ON X (B-P-G) TEST:
           BASED ON R2:            13.411     3    0.00383
           BASED ON SSR:           53.543     3    0.00000
 E**2 ON LAG(E**2) ARCH TEST:       2.641     1    0.10416
 LOG(E**2) ON X (HARVEY) TEST:     23.207     3    0.00004
 ABS(E) ON X (GLEJSER) TEST:       35.655     3    0.00000
 
 HARVEY-COLLIER  [1977] RECURSIVE T-TEST =           0.4098  WITH   45 D.F.
 HARVEY-PHILLIPS [1974] HETEROSKEDASTICITY TEST =   42.8976  WITH M =   15
 
 BACKWARDS
 
 HARVEY-COLLIER  [1977] RECURSIVE T-TEST =           2.4063  WITH   45 D.F.
 HARVEY-PHILLIPS [1974] HETEROSKEDASTICITY TEST =    0.0550  WITH M =   15


 SEQUENTIAL CHOW AND GOLDFELD-QUANDT TESTS
    N1   N2    SSE1        SSE2       CHOW    PVALUE    G-Q       DF1  DF2 PVALUE
     5   45  1843.9     0.79359E+06 0.14564     0.964 0.9527E-01    1   41 0.241
     6   44  2765.0     0.79354E+06 0.13397     0.969 0.6969E-01    2   40 0.067
     7   43  3219.2     0.79354E+06 0.12792     0.971 0.5274E-01    3   39 0.016
     8   42  3237.1     0.79354E+06 0.12771     0.972 0.3875E-01    4   38 0.003
     9   41  3271.0     0.78252E+06 0.27629     0.892 0.3093E-01    5   37 0.001
    10   40  5446.4     0.78132E+06 0.26290     0.900 0.4183E-01    6   36 0.000
    11   39  6692.9     0.78108E+06 0.24918     0.909 0.4284E-01    7   35 0.000
    12   38  6692.9     0.77818E+06 0.28892     0.884 0.3655E-01    8   34 0.000
    13   37  6753.4     0.77794E+06 0.29136     0.882 0.3183E-01    9   33 0.000
    14   36  8609.9     0.77785E+06 0.26714     0.897 0.3542E-01   10   32 0.000
    15   35  8632.2     0.77375E+06 0.32325     0.861 0.3144E-01   11   31 0.000
    16   34  9614.7     0.77054E+06 0.35404     0.840 0.3119E-01   12   30 0.000
    17   33  9669.8     0.76953E+06 0.36742     0.830 0.2803E-01   13   29 0.000
    18   32  11805.     0.76666E+06 0.37770     0.823 0.3080E-01   14   28 0.000
    19   31  14947.     0.74456E+06 0.64917     0.631 0.3614E-01   15   27 0.000
    20   30  15970.     0.74085E+06 0.68881     0.604 0.3503E-01   16   26 0.000
    21   29  16825.     0.74046E+06 0.68188     0.608 0.3341E-01   17   25 0.000
    22   28  17906.     0.74012E+06 0.67096     0.616 0.3226E-01   18   24 0.000
    23   27  18010.     0.71293E+06  1.0849     0.376 0.3058E-01   19   23 0.000
    24   26  28258.     0.71283E+06 0.92635     0.458 0.4361E-01   20   22 0.000
    25   25  34193.     0.70918E+06 0.89123     0.478 0.4821E-01   21   21 0.000
    26   24  36385.     0.70543E+06 0.91503     0.464 0.4689E-01   22   20 0.000
    27   23  36479.     0.70491E+06 0.92158     0.460 0.4275E-01   23   19 0.000
    28   22 0.13281E+06 0.60211E+06  1.0221     0.407 0.1654       24   18 0.000
    29   21 0.14109E+06 0.59854E+06 0.94890     0.445 0.1603       25   17 0.000
    30   20 0.14260E+06 0.59584E+06 0.96731     0.435 0.1473       26   16 0.000
    31   19 0.14478E+06 0.59516E+06 0.94400     0.448 0.1351       27   15 0.000
    32   18 0.14675E+06 0.59418E+06 0.92866     0.457 0.1235       28   14 0.000
    33   17 0.15048E+06 0.59328E+06 0.88528     0.481 0.1137       29   13 0.000
    34   16 0.16462E+06 0.56524E+06  1.1020     0.368 0.1165       30   12 0.000
    35   15 0.16526E+06 0.55549E+06  1.2487     0.305 0.1056       31   11 0.000
    36   14 0.16820E+06 0.55160E+06  1.2643     0.299 0.9529E-01   32   10 0.000
    37   13 0.17702E+06 0.54809E+06  1.1780     0.334 0.8809E-01   33    9 0.000
    38   12 0.17708E+06 0.54640E+06  1.2044     0.323 0.7625E-01   34    8 0.000
    39   11 0.17733E+06 0.53839E+06  1.3313     0.274 0.6588E-01   35    7 0.000
    40   10 0.17873E+06 0.53173E+06  1.4188     0.244 0.5602E-01   36    6 0.000
    41    9 0.17919E+06 0.47763E+06  2.3922     0.066 0.5070E-01   37    5 0.000
    42    8 0.18817E+06 0.18037E+06  12.477     0.000 0.1098       38    4 0.000
    43    7 0.21605E+06 0.11493E+06  15.084     0.000 0.1446       39    3 0.001
    44    6 0.22221E+06 0.11464E+06  14.638     0.000 0.9692E-01   40    2 0.000
    45    5 0.24167E+06 0.10933E+06  13.625     0.000 0.5391E-01   41    1 0.000
 
             CHOW TEST - F DISTRIBUTION WITH DF1=   4 AND DF2=  42
 |_stop


Updated: 4:20 PM 11/23/98; Prepared by: Trudy Ann Cameron; Site Index