-------------
      name:  <unnamed>
       log:  C:\D\projekte\Replication McCabe_Snyder\McCabe_Snyder_ReStat_Table_2.smcl
  log type:  smcl
 opened on:  24 Mar 2017, 09:01:22

.
. **********************************************************************
. *
. * Program McCabe_Snyder_ReStat_Table_2.DO
. *
. * Runs regressions behind Table 2 based on information collected by
. * research assistants on subsample of 1,500 observations.  Regressions
. * use panel-count-data specification, regression number of references
. * on year dummies, which are the variables of interest (giving
. * percent increase 1985 to 1995 and 1995 to 2005).
. *
. * McCabe & Snyder August 2013
. *
. **********************************************************************
.
. * Set initial Stata parameters
. version 12

. set more 1

.
. use McCabe_Snyder_ReStat_references

. codebook

-------------
isi_locisi_loc
-------------

                  type:  string (str15)

         unique values:  1,425                    missing "":  0/1,425

              examples:  "000230432800006"
                         "A1985AFY3500014"
                         "A1985AVU4600006"
                         "A1995RH55500001"

-------------
pagespages
-------------

                  type:  numeric (byte)

                 range:  [4,95]                       units:  1
         unique values:  56                       missing .:  0/1,425

                  mean:   18.5158
              std. dev:   10.3768

           percentiles:        10%       25%       50%       75%       90%
                                 7        11        17        24        31

-------------
kcodekcode
-------------

                  type:  string (str1)

         unique values:  11                       missing "":  0/1,425

              examples:  "B"
                         "E"
                         "E"
                         "N"

-------------
pyearpyear
-------------

                  type:  numeric (int)

                 range:  [1985,2005]                  units:  1
         unique values:  3                        missing .:  0/1,425

            tabulation:  Freq.  Value
                           435  1985
                           500  1995
                           490  2005

-------------
pagepage
-------------

                  type:  string (str9)

         unique values:  1,365                    missing "":  0/1,425

              examples:  "169-189"
                         "283-290"
                         "42-49"
                         "61-69"

-------------
jrnlfulljrnlfull
-------------

                  type:  string (str80), but longest is str50

         unique values:  100                      missing "":  0/1,425

              examples:  "ECONOMIC JOURNAL"
                         "JOURNAL OF BUSINESS VENTURING"
                         "JOURNAL OF INDUSTRIAL ECONOMICS"
                         "JOURNAL OF RISK AND UNCERTAINTY"

               warning:  variable has embedded blanks

-------------
bibidbibid
-------------

                  type:  string (str35)

         unique values:  1,424                    missing "":  0/1,425

              examples:  "19 (2) 203-223 2005"
                         "29 (2): 509-531 FEB 2005"
                         "40 (4) 747-778 DEC 2005"
                         "60 (1) 267-306 FEB 2005"

               warning:  variable has embedded blanks

-------------
artl_titartl_tit
-------------

                  type:  string (str80)

         unique values:  1,423                    missing "":  0/1,425

              examples:  "Corporate technology portfolios and R&D performance
                         measures: a study of technol"
                         "INTANGIBLE ASSETS, INTERNALIZATION AND FOREIGN
                         DIRECT-INVESTMENT IN MANUFACTURIN"
                         "PORTFOLIO THEORY WITH APPLICATION TO BANK ASSET
                         MANAGEMENT - SZEGO,GP"
                         "THE EFFECTS OF STATE AUTOMOBILE DEALER ENTRY
                         REGULATION ON NEW CAR PRICES"

               warning:  variable has embedded and trailing blanks

-------------
refref
-------------

                  type:  numeric (int)

                 range:  [0,278]                      units:  1
         unique values:  136                      missing .:  147/1,425

                  mean:   35.2324
              std. dev:   32.5472

           percentiles:        10%       25%       50%       75%       90%
                                10        16        27        44        67

-------------
cje(unlabeled)
-------------

                  type:  string (str29)

         unique values:  1                        missing "":  0/1,425

            tabulation:  Freq.  Value
                         1,425  "CANADIAN JOURNAL OF ECONOMICS"

               warning:  variable has embedded blanks

-------------
jite(unlabeled)
-------------

                  type:  string (str50)

         unique values:  1                        missing "":  0/1,425

            tabulation:  Freq.  Value
                         1,425  "JOURNAL OF INSTITUTIONAL AND
                                THEORETICAL ECONOMICS"

               warning:  variable has embedded blanks

-------------
subfield(unlabeled)
-------------

                  type:  string (str2)

         unique values:  2                        missing "":  0/1,425

            tabulation:  Freq.  Value
                           530  "bs"
                           895  "ec"

-------------
_merge(unlabeled)
-------------

                  type:  numeric (byte)
label  :  _merge

                 range:  [3,3]                        units:  1
         unique values:  1                        missing .:  0/1,425

            tabulation:  Freq.   Numeric  Label
                         1,425         3  matched (3)

.
. gen t1995 = pyear == 1995

. gen t2005 = pyear == 2005

.
. gen lnpages = ln(pages)

. gen lnref = ln(ref)
(153 missing values generated)

. gen lnrefpage = ln(ref/pages)
(153 missing values generated)

.
. encode jrnlfull, gen(journal)

. xtset journal
       panel variable:  journal (unbalanced)

.
. * Run regressions in two ways so can get period-over-period
. * increase as well as increase over combined period.
.
.
. * First way: t1995 variable captures 1985-95 increase
. * and t2005 variable captures combined 1985-2005 increase.
.
. xtreg lnpages t1995 t2005, fe cluster(journal)

Fixed-effects (within) regression               Number of obs      =      1425
Group variable: journal                         Number of groups   =       100

R-sq:  within  = 0.0897                         Obs per group: min =        10
       between = 0.0322                                        avg =      14.3
       overall = 0.0721                                        max =        15

                                                F(2,99)            =     39.77
corr(u_i, Xb)  = 0.0100                         Prob > F           =    0.0000

(Std. Err. adjusted for 100 clusters in journal)
-------------+----------------------------------------------------------------
             |               Robust
      lnpages |      Coef.    Std. Err.       t    P>|t|      [95% Con f. Interval]
-------------+----------------------------------------------------------------
       t1995 |     .220885    .0352495      6.27    0.000      .1509423     .2908277
       t2005 |    .3829722    .0438155      8.74    0.000      .2960327     .4699117
       _cons |    2.553149    .0241617    105.67    0.000      2.505207     2.601091
-------------+----------------------------------------------------------------
     sigma_u |     .29575
     sigma_e |  .49933414
         rho |  .25970123   (fraction of variance due to u_i)
-------------+----------------------------------------------------------------

. test t1995 = t2005


 ( 1)  t1995 - t2005 = 0


       F(  1,    99) =   17.84
            Prob > F =    0.0001

.
. xtreg lnrefpage t1995 t2005, fe cluster(journal)

Fixed-effects (within) regression               Number of obs      =      1272
Group variable: journal                         Number of groups   =       100

R-sq:  within  = 0.0175                         Obs per group: min =         3
       between = 0.0386                                        avg =      12.7
       overall = 0.0155                                        max =        15

                                                F(2,99)            =      8.87
corr(u_i, Xb)  = 0.0272                         Prob > F           =    0.0003

(Std. Err. adjusted for 100 clusters in journal)
-------------+----------------------------------------------------------------
             |               Robust
    lnrefpage |      Coef.    Std. Err.       t    P>|t|      [95% Con f. Interval]
-------------+----------------------------------------------------------------
       t1995 |    .1106642    .0470047      2.35    0.021      .0173966     .2039317
       t2005 |    .1850883    .0440111      4.21    0.000      .0977607     .2724159
       _cons |    .3232377    .0282872     11.43    0.000      .2671098     .3793656
-------------+----------------------------------------------------------------
     sigma_u |  .45771125
     sigma_e |  .55490413
         rho |  .40489414   (fraction of variance due to u_i)
-------------+----------------------------------------------------------------

. test t1995 = t2005


 ( 1)  t1995 - t2005 = 0


       F(  1,    99) =    2.75
            Prob > F =    0.1006

.
. xtreg lnref t1995 t2005, fe cluster(journal)

Fixed-effects (within) regression               Number of obs      =      1272
Group variable: journal                         Number of groups   =       100

R-sq:  within  = 0.1057                         Obs per group: min =         3
       between = 0.0440                                        avg =      12.7
       overall = 0.0799                                        max =        15

                                                F(2,99)            =     56.87
corr(u_i, Xb)  = 0.0063                         Prob > F           =    0.0000

(Std. Err. adjusted for 100 clusters in journal)
-------------+----------------------------------------------------------------
             |               Robust
        lnref |      Coef.    Std. Err.       t    P>|t|      [95% Con f. Interval]
-------------+----------------------------------------------------------------
       t1995 |    .3329895    .0490153      6.79    0.000      .2357325     .4302465
       t2005 |    .5618741    .0536971     10.46    0.000      .4553275     .6684208
       _cons |    2.937834    .0315794     93.03    0.000      2.875174     3.000494
-------------+----------------------------------------------------------------
     sigma_u |  .50200264
     sigma_e |  .65453902
         rho |  .37036492   (fraction of variance due to u_i)
-------------+----------------------------------------------------------------

. test t1995 = t2005


 ( 1)  t1995 - t2005 = 0


       F(  1,    99) =   18.85
            Prob > F =    0.0000

.
.
. * Redefine so t1995 variable still captures 1985-95 increase
. * but t2005 variable captures just 1995-2005 increase.
.
. replace t1995 = 1 if t2005 == 1
(490 real changes made)

.
. xtreg lnpages t1995 t2005, fe cluster(journal)

Fixed-effects (within) regression               Number of obs      =      1425
Group variable: journal                         Number of groups   =       100

R-sq:  within  = 0.0897                         Obs per group: min =        10
       between = 0.0322                                        avg =      14.3
       overall = 0.0721                                        max =        15

                                                F(2,99)            =     39.77
corr(u_i, Xb)  = 0.0100                         Prob > F           =    0.0000

(Std. Err. adjusted for 100 clusters in journal)
-------------+----------------------------------------------------------------
             |               Robust
      lnpages |      Coef.    Std. Err.       t    P>|t|      [95% Con f. Interval]
-------------+----------------------------------------------------------------
       t1995 |     .220885    .0352495      6.27    0.000      .1509423     .2908277
       t2005 |    .1620871    .0383803      4.22    0.000      .0859323      .238242
       _cons |    2.553149    .0241617    105.67    0.000      2.505207     2.601091
-------------+----------------------------------------------------------------
     sigma_u |     .29575
     sigma_e |  .49933414
         rho |  .25970123   (fraction of variance due to u_i)
-------------+----------------------------------------------------------------

.
. xtreg lnrefpage t1995 t2005, fe cluster(journal)

Fixed-effects (within) regression               Number of obs      =      1272
Group variable: journal                         Number of groups   =       100

R-sq:  within  = 0.0175                         Obs per group: min =         3
       between = 0.0386                                        avg =      12.7
       overall = 0.0155                                        max =        15

                                                F(2,99)            =      8.87
corr(u_i, Xb)  = 0.0272                         Prob > F           =    0.0003

(Std. Err. adjusted for 100 clusters in journal)
-------------+----------------------------------------------------------------
             |               Robust
    lnrefpage |      Coef.    Std. Err.       t    P>|t|      [95% Con f. Interval]
-------------+----------------------------------------------------------------
       t1995 |    .1106642    .0470047      2.35    0.021      .0173966     .2039317
       t2005 |    .0744241    .0448997      1.66    0.101     -.0146665     .1635148
       _cons |    .3232377    .0282872     11.43    0.000      .2671098     .3793656
-------------+----------------------------------------------------------------
     sigma_u |  .45771125
     sigma_e |  .55490413
         rho |  .40489414   (fraction of variance due to u_i)
-------------+----------------------------------------------------------------

.
. xtreg lnref t1995 t2005, fe cluster(journal)

Fixed-effects (within) regression               Number of obs      =      1272
Group variable: journal                         Number of groups   =       100

R-sq:  within  = 0.1057                         Obs per group: min =         3
       between = 0.0440                                        avg =      12.7
       overall = 0.0799                                        max =        15

                                                F(2,99)            =     56.87
corr(u_i, Xb)  = 0.0063                         Prob > F           =    0.0000

(Std. Err. adjusted for 100 clusters in journal)
-------------+----------------------------------------------------------------
             |               Robust
        lnref |      Coef.    Std. Err.       t    P>|t|      [95% Con f. Interval]
-------------+----------------------------------------------------------------
       t1995 |    .3329895    .0490153      6.79    0.000      .2357325     .4302465
       t2005 |    .2288846    .0527218      4.34    0.000      .1242732      .333496
       _cons |    2.937834    .0315794     93.03    0.000      2.875174     3.000494
-------------+----------------------------------------------------------------
     sigma_u |  .50200264
     sigma_e |  .65453902
         rho |  .37036492   (fraction of variance due to u_i)
-------------+----------------------------------------------------------------

.
.
.
.
.
end of do-file

. exit, clear