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Table 2 Summary statistics of the dataset

From: Citation counts in transportation research

Variable code Definition Mean S.D. Min Max
Dependent variable:
CI Citations per article 28.08 29.58 0 294
Article characteristics:
KW Keywords 8.84 3.84 1 24
RF References 25.96 16.73 0 167
WA Words in abstract 158.71 61.59 0 464
WT Words in title 10.75 3.66 1 28
Author characteristics:
ANa Place in alphabet of first authors surname 10.96 7.18 1 26
GE Gender (1 = female, 0 = male) 0.13 0.34 0 1
EN Language (1 = English, 0 = not English) 0.57 0.50 0 1
NA Number of authors (1 = more than one, 0 = one) 0.77 0.42 0 1
AC Number of countries (1 = more than one, 0 = one) 0.20 0.40 0 1
Name of journals:
TR Transportation 0.13 0.34 0 1
PA Transportation Research Part A 0.27 0.44 0 1
PB Transportation Research Part B 0.28 0.45 0 1
TS Transportation Science 0.19 0.39 0 1
JT Journal of Transport Economics and Policy 0.12 0.33 0 1
Publication year:
Y 2000 Publication year (1 = 2000, 0 otherwise) 0.17 0.38 0 1
Y 2001 Publication year (1 = 2001, 0 otherwise) 0.20 0.40 0 1
Y 2002 Publication year (1 = 2002, 0 otherwise) 0.22 0.41 0 1
Y 2003 Publication year (1 = 2003, 0 otherwise) 0.21 0.41 0 1
Y 2004 Publication year (1 = 2004, 0 otherwise) 0.20 0.40 0 1
  1. a Articles written by first authors whose surname begin with the letter A is given the value 1, a first author whose surname begin with the letter B is given the value 2, etc.