Speculative Bubble
A temporary market condition created through excessive buying, and an unfounded run-up in prices occurs.
Investopedia Commentary
Speculative bubbles are generally a result of the "bandwagon effect." Investors, seeing an upward trend in prices, quickly enter long positions in an attempt to participate in the stocks' profitability. Typically, these bubbles are followed by even faster sell-offs once the prices begin to decline.
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