All kinds of abnormalities are concerned on stock market in the foreign financial documents these years, such as January effect, disposition effect, momentum effect, herd behavior.

近年来，国外财务学界的研究文献大量地关注证券市场的各种异常，如一月效应、处置效应、动量效应、羊群行为等等。

youdao

We controlled for other well-known fixed calendar (we call them Gregorian anomalies), notably,day of the week effect, like Monday,January effect, Halloween effect, and none of those factors explained results.

VOA: standard.2010.08.05

it takes effect in January. The new law may not go as far as some would like, but the action is historic.

VOA: special.2009.05.27

Since the agreement went into effect in January, some textile factories have gone out of business.

VOA: standard.2010.05.13

What about combining of these two factors, The January Effect in small-caps and the Presidential Cycle?

FORBES: Get Ready For A Turbo Charged January Effect

By December 14, the weekly OBV was above its WMA, confirming the January effect.

FORBES: The Power of Volume

The January effect is the tendency of low price, small-capitalization stocks to outperform in January.

FORBES: Why There May Be A January Effect For Large-Cap Stocks