Here is the situation. I am in US for 2 and half years. I am qualified for substantial presence test. I came here in F-1 student visa. Graduated from one of US univ and have been working as a full time employee. I need to figure out about my residency stautus(either Resident alien or Non-resident alien) for tax return to use the right forms. it created the confusion to file ssn and medicare tax refund. If anyone has alredy passed through this situation your information in this regard will be highly appreciated.