Adam Jeffery | CNBC

There is significant worry that the recent decline in copper and China's economic woes might be the start of a wider correction. There are certainly some concerns reflected in the market internals: fewer new highs overall, and no components having hit new highs. Still, it's hard to see imminent signs of a significant market drop. The advance/decline line is still near a new high, and that usually turns down well in advance of a significant market correction. I would also note that financials have been market leaders recently, with the main at a new high on Monday. They usually turn down early as well.



Some say that if you can't take the whole market down, try and slow down the 'Big Momentum' names. Much was made overnight that certain sectors are too "frothy"; bears were gloating overnight over the big declines yesterday in fuel cell stocks like PLUG and FuelCell. The lines of attack from bears are fairly easy to see: the obvious "Big Mo" targets include medical/biotech. Indeed, there are some big gains in that sector this year. Here are just a few (percentage change): Illumina 50 percent Alexion 32 percent Actavis 25 percent Biogen Idec 20 percent Regeneron 19 percent Still, these companies are much better financed, and generally have stronger drugs (even if there are only or two per company) than in the last major shakeup from 2000 to 2002. Another obvious choice is anything in the vague "cloud computing" space, which has also seen good gains: F5 Networks 23 percent Workday 21 percent Vmware 15 percent Cvent 15 percent Salesforce.com 10 percent Big Data is another obvious choice: Tableau Software (DATA) and Splunk (SPKK) for example are up 32 percent and 23 percent respectively this year. But none of these sectors have cracked yet.



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