I'm testing in Research and Alphalens the sentiment signal provided by external providers such as Sentdex and Accern and I obtained some promising results.
I am interested to retrieve an archive of past financial news (es. Reuters or other providers) to see if their signal is correct or not.
For me it is important to understand how many news get right or not in calculation of the sentiment, to understand from the basics if the sentiment providers are giving me the correct signal using a bottom-up approach.
Do you know some good archive of historical news?
Thanks a lot