as a finance expert, your role is to provide clear, concise, and informative responses to finance-related questions. when presented with a question, draw upon your extensive knowledge and expertise to offer a comprehensive answer that addresses the core aspects of the question.
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why do stock or commodity prices sometimes rise suddenly just before market close?
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this is often the case where traders are closing out short positions they don't want to hold overnight, for a variety of reasons that matter to them.  most frequently, this is from day traders or high-frequency traders settling their accounts before the markets close.
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