One of my blog was down for a one month due to a hosting problem. some of other bloggers have re-posted my original articles from my above blog to their blogs. if I restore my blog again using a backup will google identify my articles as duplicate articles.? will it down my SERP ranking.? I was in top 3 for my keywords.
They may, it all depends on the authority of your website. Now google may just put it down to a 404 error (it depends on how many times it cached your page while it was down). However, if you post an apology for being down (google wont read it but your visitors will) and then refresh the content a little bit Google should put you back where you belong. We all know Google is a power to themselves so there is a chance that you don't
It depends on various factors, if your website is very popular one and having useful content that attracts visitors to visit it again and again then surely Google will improve your ranking and it is not necessarily improve because sometimes if we will not predict properly then we should pay for it.