部分面板数据如下:
city | year | y | x1 | x2 | x3 | x4 |
1 | 2001 | 0.008921 | 10.51 | 16.78 | 10.17 | 5.79 |
1 | 2002 | 0.00938 | 9.19 | 18.44 | 11.49 | 6.35 |
1 | 2003 | 0.009589 | 11.17 | 20.83 | 13.46 | 6.91 |
1 | 2004 | 0.009761 | 14.15 | 23.34 | 15.36 | 9.10 |
1 | 2005 | 0.01029 | 18.45 | 26.49 | 18.98 | 11.35 |
1 | 2006 | 0.011236 | 17.17 | 32.42 | 21.60 | 12.75 |
1 | 2007 | 0.012128 | 24.83 | 43.53 | 36.15 | 16.70 |
1 | 2008 | 0.012574 | 34.79 | 58.33 | 41.04 | 21.78 |
1 | 2009 | 0.01401 | 44.55 | 44.86 | 44.82 | 23.54 |
1 | 2010 | 0.015321 | 68.51 | 82.25 | 30.46 | 31.41 |
1 | 2011 | 0.016118 | 99.63 | 109.91 | 7.17 | 36.27 |
1 | 2012 | 0.018123 | 129.54 | 140.92 | 270.66 | 46.26 |
2 | 2001 | 0.008415 | 24.53 | 14.92 | 7.37 | 5.88 |
2 | 2002 | 0.008637 | 26.67 | 16.15 | 8.86 | 6.56 |
2 | 2003 | 0.009237 | 28.12 | 17.55 | 11.05 | 7.27 |
2 | 2004 | 0.009656 | 35.36 | 18.75 | 12.83 | 8.31 |
2 | 2005 | 0.010695 | 43.27 | 21.91 | 15.05 | 10.46 |
2 | 2006 | 0.011615 | 52.25 | 28.32 | 19.08 | 12.50 |
2 | 2007 | 0.011916 | 55.95 | 47.52 | 48.52 | 14.49 |
2 | 2008 | 0.01307 | 84.58 | 57.69 | 57.72 | 18.22 |
2 | 2009 | 0.014291 | 97.31 | 63.83 | 61.46 | 20.79 |
2 | 2010 | 0.014415 | 115.40 | 73.30 | 44.37 | 23.75 |
2 | 2011 | 0.016583 | 102.76 | 98.30 | 64.01 | 27.34 |
2 | 2012 | 0.01851 | 224.36 | 114.68 | 339.24 | 36.66 |
3 | 2001 | 0.003754 | 1.64 | 6.45 | 4.03 | 1.26 |
3 | 2002 | 0.00377 | 2.01 | 7.40 | 4.71 | 1.65 |
3 | 2003 | 0.00397 | 1.68 | 8.11 | 4.97 | 1.87 |
3 | 2004 | 0.004151 | 2.18 | 7.88 | 3.52 | 1.52 |
3 | 2005 | 0.004471 | 5.08 | 9.73 | 6.49 | 3.20 |
3 | 2006 | 0.004706 | 1.14 | 1.82 | 1.82 | 0.34 |
3 | 2007 | 0.005669 | 11.01 | 16.36 | 13.52 | 3.91 |
3 | 2008 | 0.006136 | 12.93 | 20.39 | 14.20 | 4.52 |
3 | 2009 | 0.006948 | 22.66 | 27.31 | 16.74 | 6.48 |
3 | 2010 | 0.008147 | 34.16 | 31.14 | 12.60 | 9.63 |
3 | 2011 | 0.009831 | 33.60 | 41.88 | 24.01 | 10.31 |
3 | 2012 | 0.01118 | 78.39 | 65.48 | 144.07 | 29.73 |
4 | 2001 | 0.00582 | 3.29 | 6.32 | 2.75 | 0.69 |
4 | 2002 | 0.006372 | 3.57 | 7.09 | 2.77 | 0.81 |
4 | 2003 | 0.00665 | 3.81 | 7.81 | 3.39 | 2.73 |
4 | 2004 | 0.006897 | 4.76 | 8.97 | 5.59 | 2.56 |
4 | 2005 | 0.007562 | 2.47 | 9.12 | 3.86 | 1.71 |
4 | 2006 | 0.007386 | 3.24 | 11.73 | 5.19 | 2.02 |
4 | 2007 | 0.007159 | 5.24 | 15.51 | 8.84 | 2.42 |
4 | 2008 | 0.007907 | 9.13 | 21.25 | 10.65 | 3.46 |
4 | 2009 | 0.008602 | 14.89 | 27.87 | 11.63 | 6.82 |
4 | 2010 | 0.009417 | 18.90 | 37.34 | 9.34 | 7.63 |
4 | 2011 | 0.00983 | 18.00 | 41.71 | 18.50 | 8.28 |
4 | 2012 | 0.010795 | 111.73 | 124.42 | 236.36 | 36.02 |
疑问:长面板是否需要转换成宽型面板?