geo cepii表格里的英文数据说明表示什么意思

iso2	iso3	cnum	country	pays	area	dis_int	landlocked	continent	city_en	city_fr	lat	lon	cap	maincity	citynum	langoff_1	langoff_2	langoff_3	lang20_1	lang20_2	lang20_3	lang20_4	lang9_1	lang9_2	lang9_3	lang9_4	colonizer1	colonizer2	colonizer3	colonizer4	short_colonizer1	short_colonizer2	short_colonizer3
AW	ABW	533	Aruba	Aruba	193	5.225315	0	America	Oranjestad	Oranjestad	12.55	-70.1	1	1	2	Dutch	Spanish	.	Dutch	English	Papiamento	.	.	.	.	.	NLD	.	.	.	.	.	.
AF	AFG	4	Afghanistan	Afghanistan	652225	303.7614	1	Asia	Kabul	Kaboul	34.51667	69.2	1	1	25	Persian	.	.	Persian	Pashtu	.	.	Hazaragi	Uzbek	.	.	.	.	.	.	GBR	.	.
AO	AGO	24	Angola	Angola	1246700	419.9666	0	Africa	Luanda	Luanda	-8.833333	13.25	1	1	25	Portuguese	.	.	Portuguese	Umbundu	Mbundu Loanda	.	Kongo	.	.	.	PRT	.	.	.	.	.	.
AI	AIA	660	Anguilla	Anguilla	102	3.79869	0	America	The Valley	The Valley	18.21667	-63.06667	1	1	2	English	.	.	English	Leeward Caribbean Creole English	.	.	.	.	.	.	GBR	.	.	.	.	.	.
AL	ALB	8	Albania	Albanie	28748	63.77311	0	Europe	Tirana	Tirana	41.33333	19.81667	1	1	25	Albanian	.	.	Albanian	.	.	.	.	.	.	.	TUR	.	.	.	.	.	.
AD	AND	20	Andorra	Andorre	453	8.005398	0	Europe	Andorra la Vella	Andorre-la-Vieille	42.5	1.5	1	1	7	Catalan	Spanish	.	Catalan	Spanish	.	.	.	.	.	.	.	.	.	.	.	.	.
AN	ANT	530	Netherland Antilles	Antilles néerlandaises	960	11.65385	0	America	Willemstad	Willemstad	12.1	-68.93333	1	1	5	Dutch	Spanish	.	Dutch	Papiamento	.	.	English	.	.	.	NLD	.	.	.	.	.	.

我截取了表格的前几行，第一行的英文完全不懂什么意思，希望大神指点迷津，急用数据！！！

1.iso2, iso3, cnum: ISO codes in two and three characters, and in three numbers respectively.
2.country, pays: Name of country in English and French respectively
3.area: Country’s area in km2
4.dis_int: Internal distance of country i, dii = .67parea/π (an often used measure of
average distance between producers and consumers in a country）
5. landlocked: Dummy variable set equal to 1 for landlocked countries.
6.continent: Continent to which the country is belonging
7. langoff_i: Official or national languages and languages spoken by at least 20% of the
population of the country
8. lang20_i: Languages (mother tongue, lingua francas or second languages) spoken by at
least 20% of the population of the country.
9.lang9_i: Languages (mother tongue, lingua francas or second languages) spoken by between 9% and 20% of the population of the country. 6.
10. colonizeri: Colonizers of the country for a relatively long period of time and with a
substantial participation in the governance of the colonized country.
• short_colonizeri: Colonizers of the country for a relatively short period of time or
with only low involvement in the governance of the colonized country
• city_en, city_fr: Names of capitals or main cities of the country in English and
French.
• lat, lon: Latitude and longitude of the city.9
• cap: Variable equals to 1 if the city is the capital of the country, to 0 if the city is the most
populated city (maincity equals to 1) but not the capital, and to 2 in the cases of two
capitals, if the city is the most populated but the “second” capital or the previous capital10.
• maincity: Variable coded as 1 when the city is the most populated of the country and as
2 otherwise11.
• citynum: Number of cities for each country used to calculate our weighted distances described in the next section.

805051762@qq.co 发表于 2016-11-27 10:30
1.iso2, iso3, cnum: ISO codes in two and three characters, and in three numbers respectively.
2. ...

谢谢～