She explains that the strategy did not work as predicted because of what's called a population level effect.

VOA: standard.2010.03.22

Cause and effect below a certain level of definition is blurred.

在某种程度的定义的下的,因果关系是模糊的。

麻省理工公开课 - 固态化学导论课程节选

"I have agreed in principle to a new British force level of 9,500, which will be put into effect once these conditions are met,".

VOA: standard.2009.10.14

Alter the levels of those gases and you alter the level of the effect.

ECONOMIST: Climate change: Getting real | The

This incorporates a safety factor of 1, 000 on the lowest observed adverse effect level of antinomy in animals--in other words, the first statistically significant health problem in animals came from inhaling antimony at a level of 9000 micrograms per meter cubed.

FORBES: Medialand

One of the reasons for local economic crises is that national Governments have passed on an increasing array of service obligations to the local level, in effect creating a new cadre of local economic actors who were not necessarily up to the job.

FORBES: Europe in Crisis Without Systemic and Citizen Innovation