The phrase "a long position in" is correct and usable in written English.
It is typically used in financial contexts to indicate that an investor has bought a security with the expectation that its price will rise.
Example: "Investors are encouraged to take a long position in the stock market as it shows signs of recovery."
Alternatives: "a bullish stance on" or "an investment in".
She took a long position in Vestel a year ago and is now up almost 100% on her investment.
Meanwhile, at least one hedge fund appears to be taking a long position in Overstock.com.com
In "global macro" plays, a fund takes a long position in one country's currency and shorts the currency of another (this is also done with government debt).
"That doesn't make any sense to me at all, frankly," said Mr. Murphy, who has neither a short nor a long position in the company.
Goldman marketed a "long" position in Abacus to clients like IKB Deutsche Industriebank, a German bank that thought the value of the portfolio would go up.
The authors then took a long position in the market with the highest forecasted return and a short position in the one expected to do worst.
From a risk-management point of view, this was perfect: have a long position in the low-risk asset, and a short one in the higher-risk one.
I also happen to know that many economists have a large fraction of their wealth in a long position in the "housing services" industry.
Mr. Loeb had announced a long position in Herbalife after another hedge fund manager, William A. Ackman, said he was betting against it.
If you thought that there is some chance that treasury yields will only rise slightly over the next few years, but also some risk of solvency problems and a panic flight from the dollar, what you might want to do is to take a long position in treasuries hedged with a long position in commodities.
Another of Dalio's articles that stuck in Prince's memory was titled "What Is a Jeweler?" It described a jeweller as basically an investor with a long position in gold and precious stones.
