First of all, the concept of duration has nothing to do with the actual period of time for which an investment is being held. Duration is a measure for the sensitivity of a bond position (or a position in instruments related to bonds, such as bond futures, for example) - the longer the duration, the higher the position risk. Also, for conceptional reasons duration is never used in the context of equities - Macaulay's duration formula comprises the repayment of the bond, whereas equities normally do not provide for repayment of the invested capital (see the URL provided below for a simple definition of Macaulay duration).

A [net] short position denotes a position where net sales exceed net purchases - IOW a position that benefits from falling prices. Although "short duration" is sometimes used to refer to a position with a short duration (= low risk), the key to what is meant here is in the cross-reference to an offsetting long position in euro-zone bonds: the overall position is a spread between US and euro bonds that is set on the yield differential between the two bond markets to widen. (A short position in US bonds benefits when US yields rise; the long position in euro bonds will benefit if euro yields fall - a spread position will benefit if US yields go up relative to euro yields.)

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