I am monitoring a keyword for my website, and I noticed it's ranked different at home when compared with work, school, and various other locations such as friends. Why is that? At home it's ranked 1 and at other palces, it's ranked on first page.
It happen with your cookies and cached problem. You have to clear your history, cookies and cache first and then check your rank.
Please be reminded that google has different search engine. Which means we are accessing different data center on different PC and location which lead to different results.