coal.def

x2 x3 x4 x6 x6 x7 y

  OBS: 1985 cross-section of 63 state-owned coal mining firms in China
  

	x2	=	capital (1,000 yuan units)
	x3	=	labor (number of people)
	x4	=	electricity consumption (10,000 kilowatt units)
	x5	=	timber consumption (in cubic metres)
	x6	=	gun-powder consumption (in kilograms)
	x7	=	steel consumption (in tonnes).
	y	=	coal output (10,000 ton units)
  
              
    Variable |       Obs        Mean    Std. Dev.       Min        Max
-------------+--------------------------------------------------------
          x2 |        63      531154    426592.9      58600    2091000
          x3 |        63    22369.21    15549.34       3396      71046
          x4 |        63    15165.63    13701.72       1351      57021
          x5 |        63    35619.05    29753.28       5400     141200
          x6 |        63     1631067     1596040       2400    7802200
-------------+--------------------------------------------------------
          x7 |        63    6480.476    6099.498        730      35960
           y |        63    577.7619    520.2461        119       3080