Components of clutter
广告竞争的组成（个人觉得clutter用“混乱”不容易理解所以翻译为“竞争”）
This raises the question:What other ads does a particular brand compete with?
这就带来一个疑问：某一品牌的广告究竟和其他什么样的广告相互竞争呢?
In the broadest sense it competes with all other ads-even those not in the same product category.
从广义说,它与其他所有广告包括不同种类商品之间的广告都有竞争.
This is known as the general level of on-air clutter and any ad has to break through it.
正在播出的所有广告之间的竞争叫做综合竞争（全面竞争）,所有广告都不得不参与其中.
This general level of clutter is relatively constant,at least in the short term.
综合竞争在短期内看不出多少优劣.
However,it has tended to grow over the long term not only because of more time given to ads but also because of an increase in the use of shorter-length commercials.
但从长期讲会产生变化,这不仅因为广告播出的时间长了,还因为短广告使用的增多.
Shorter-length commercials boost the total number of commercials on air and thus the number that people see in any given time period,and increases the general impression that there is more advertising overall.
短广告增加了播出广告的次数,使观众在同一时间内看到更多数量的广告,并形成此类广告更多的印象.
As well as the general level of clutter there is,even more importantly,category clutter.
同综合竞争一样,甚至更为重要一些,这就是同类竞争.
The ad in question competes with other ads in the same product category.This is called category clutter ,and this does vary from week to week.
同类商品广告之间的竞争称做同类竞争.这类竞争最为激烈（刚才文章说到广告的播出是按week算的,vary from week to week表示此种竞争每一周都有诸多变化,所以意译为竞争激烈）.
What may be surprising to many readers is that the ad also competes with any other ads for the same brand that may be aired in the same week.
可能令许多读者吃惊的是,相同时间段播出的同一商品多个不同广告之间也存在竞争.
That is,multiple but similar advertising executions for the same brand frequently compete among themselves and can set up interference effects that impede their individual effectiveness(especially with low-involved audiences).
也就是,同品牌多个相似的广告也会经常竞争,产生干扰影响,削弱各自广告的效果（特别对于分辨力差的观众）
