Variables

Definition

Observation

Mean

Std

Minimum

Maximum

1) Annual county data

nightlight

Night light brightness (range 0 - 63)

14,131

5.450

7.910

0.028

62.165

d_light

Annual growth of light intensity (%)

14,131

33.677

145.442

−1100.975

1904.348

pceducate

Number of primary and secondary school students per 10,000 people

13,581

785.163

747.191

0.030

3642.145

palabor

Population per unit of land area (10,000 people/square kilometers)

13,652

170.172

258.965

0.000

1952.392

pdinvest

Investment in fixed assets per unit of GDP

8377

0.464

0.296

0.007

7.127

pcgengdi

Per capita arable land area (ha./10,000 people)

7925

234.614

468.871

0.000

7428.728

pcgdp

Per capita GDP (10,000 yuan)

9079

0.653

1.362

0.000

29.527

2) County time-point data

diversity

Clan surname diversity index

1087

0.607

0.353

0

0.983

surname_count

Number of clan surnames

1087

10.850

16.013

1

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