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I am applying for a PhD program in Computer Science. The university asks each applicant to hand in an optional personal history statement. I have detailed my research experience, career goals clearly in my statement of purpose. Hence I don't really know what I should write in a personal history statement. I am an average Asian student and do not have anything special. Any ideas on this essay?
EDIT: below is what they actually require:
The purpose of this optional essay is to get to know you as an individual and as a potential graduate student, and to understand how your background will add to the diversity of our school. Please describe how your personal background has motivated you to pursue a graduate degree. You may discuss educational, familial, cultural, socioeconomic, or personal experiences or challenges; gender identity; community services, outreach services, first-generation college status or other matters relevant to your decision to pursue graduate education. Please note that the Personal History Statement is not meant to be a general autobiography.