The Country Similarity Index attempts to quantify how similar countries are to each other relative to other countries. The index is a statistically-based way to measure this. 20% of the index is based on demographics. 20% of a country’s demographic score (4% of the overall Country Similarity Index score) is allocated for ethnicity. Ethnicity included two major categories: native language and religious background. The following is an explanation on how they were calculated:
Language families are languages that descended through a common language in the past. By far, the most widely spoken language family is Indo-European. It includes most European languages, as well as Persian, Hindustani, and Bengali. The Niger-Congo language family is dominate in Sub-Saharan Africa. Another major language family is Afroasiatic. It includes Arabic, Somali, and Hebrew. While it is disputed whether Mongolian and Turkic languages actually came from a common ancestral language, they are considered part of the same Altaic language family for the purposes of this study, since they share many similarities.
Even though languages may have a common ancestral language, they could still be extremely different. For instance, German and Bengali are both Indo-European languages, but have very little else in common. German is much more closely related to Dutch, English, and Scandinavian languages. This is known as the Germanic language branch. For this study, the branches were determined by elinguistics.com. Languages on the same branch had a common ancestry no more than 4,000 years ago.
Although the most spoken native language is Mandarin Chinese, it is not widely used outside of China and Taiwan. Singapore and Brunei are the only other countries where more than 10% of their population speaks it natively. The Spanish language is more wide spread. A majority of the people in at least 20 countries speak Spanish natively. The only other languages with at least 10 countries are English and Arabic. French is the official language of many countries but the people in a majority of those countries do not speak it natively. Half credit was given to languages that are extremely similar and only diverged in the last few centuries, even though they are not considered to be the same language (as determined by elinguistics.net). Some examples: Danish and Norwegian, Afrikaans and Dutch, Kazakh and Kyrgyz. Other languages may have two different names, but are essentially the same languages and are mutually intelligible like Romanian and Moldovan.
The CIA World Factbook and elinguistics were the sources of the information:
The most widespread religion in the world is Christianity, followed by Islam. Hinduism is widespread among Indians, while Buddhism is most heavily concentrated in Southeast Asia. Israel is the only country with a majority of Jewish people. East Asian folk religions and traditional African religions are also seen alongside these major religions.
Although different people may be a part of the same major religion, there can be significant differences in their traditions and practices. Some religions were broken down into specific denominations as follows:
Christianity — Eastern Orthodox, Oriental Orthodox, Catholic, Protestant, Mormon
Islam — Sunni, Shia, Ibadi
Buddhism — Theravada, Mahayana, and Vajrayana
The CIA World Factbook was the source of the information:
The languages and religions of two different countries are compared using the following method:
Example 1: In Estonia, 68.5% of people speak Estonian natively, while 29.6% speak Russian natively. Therefore, Estonia gets 0.7 Estonian points and 0.3 Russian points. In Lithuania, 82% of people speak Lithuanian natively, 8% speak Russian natively, and 5.6% speak Polish natively. Therefore, Lithuania gets 0.8 Lithuanian points, 0.1 Russian points, and 0.1 Polish points. When language in Estonia and Lithuania is compared, they get credit for just 0.1 out of 1.0 points, since so few people in Lithuania speak Estonian or Russian natively.
Example 2: Indonesia is 87% Muslim and 10% Christian, therefore it gets 0.9 Muslim points and 0.1 Christian points. Ethiopia is 67% Christian and 31% Muslim, therefore it gets 0.7 Christian points and 0.3 Muslim points. When religion in Indonesia and Ethiopia is compared, they receive credit for 0.3 points for Muslims and 0.1 for Christians, adding up to a total of 0.4 points out of 1.0 points.
Obviously there is no one clear way to determine how similar one country is to another. How would you quantify how similar one country is to another?
Please leave any thoughts in the comments section.