The best letters of recommendation come from persons who have seen you perform in some capacity – student, student leader, employee, researcher, volunteer. The weakest letters are of the “character reference” variety (from the clergy member who knows you only as a person who attends weekly services, for example) or come from influential persons (your mother’s college roommate’s sister, who is on an admissions committee) who barely know you.
A letter need not be lengthy to be effective, and the writer need not know you well. An instructor’s letter which describes the content and difficulty of a course and rates your performance as much stronger than that of many other students tells an admissions committee something significant about you.
It’s important to avoid repetition and duplication in your letters. “Only one recommendation per single source” is a good rule of thumb. Each letter should highlight a different facet of you and your accomplishments and, ideally, present you from a different vantage point.If you have a job in which you report to more than one person, don’t ask each person for a letter. Rather, ask your supervisors to collaborate on a single letter. Similarly, if you’re a Biology major, don’t ask three Biology professors for letters. Granted, each may be able to speak highly of you; however, they all will be making similar observations from a single frame of reference. Your goal should be a mix of letters from a variety of experiences and perspectives.
Last but not least, request your letters in person whenever possible and give everyone you ask for a letter of recommendation a copy of your resume and your personal statement. Ask the person if s/he is able to write you a strong letter, and offer to provide any additional material the person requests.
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