"You can now read X% of all real articles" - What does this mean statistically?
Does "You can now read 40% of all real Spanish articles" mean:
(1) "Given 100 articles written in Spanish, I can read 40 of them at 100% comprehension"
or does it mean
(2) "Given 100 articles written in Spanish, I can read 100 of them at 40% comprehension"
There are more possibilities: (3) You can read 40 % of the words that appear in written Spanish. (4) You can read 40 % of the word occurrences that appear in Spanish. (So every the on a page counts separately, for example.) If I had to guess what is meant, I would pick (4).
you can read more about it here: http://www.lingholic.com/how-many-words-do-i-need-to-know/. it's not a scientific article, but it is a very clear explanation of the Pareto principle. you really don't have too know ten thousands of words to read a language:-) however there is a difference if you learn a language from a completely different culture. the languages on duolingo at this point are roman and german languages, so that would not be a problem.
Duolingo has never shown me this screen.... is it some kind of A/B testing beta roll-out? Or- do I have to do something special to unlock this?
I goggled around and found a picture: https://lh3.googleusercontent.com/-9Ti3X2okJkQ/Uh4_tbOCldI/AAAAAAAAD-8/bSd38_cv7Tw/w988-h568-no/Capture.JPG