Although we don't believe in timing the market or panicking over daily movements, we do like to keep an eye on market changes -- just in case they're material to our investing thesis.

Despite hitting a record high on Wednesday (by just two one-hundredths of a point), stocks were down on the week, with the S&P 500 declining by 0.2%. The narrower Dow Jones Industrial Average (DJINDICES:^DJI), meanwhile, managed to put up a 0.1% gain. Within the S&P 500, technology large caps Hewlett-Packard (NYSE:HPQ) and Juniper Networks (NYSE:JNPR) were standout performers, while electronics retailer Best Buy (NYSE:BBY) brought up the rear.

Juniper Networks(NYSE:JNPR) was the third-best performing stock in the S&P 500 this week, with a 10.5% gain, ostensibly on news that activist hedge fund Elliot Management has taken a 6.2% stake and will press for cost cuts, share repurchases, and the payment of a dividend to boost the stock price to $35 to $40. I've followed Elliot for a very long time, and they are smart, value-focused, and very determined -- they once had an Argentine warship seized after Argentina defaulted on debt that Elliot happened to own. Juniper had better sharpen its pencils, so to speak.

Hewlett-Packard's(NYSE:HPQ) stock was the sixth best performer in the S&P 500 this week, gaining 7.6%, a rise that appears to have been driven by analyst actions. On Monday, Atlantic Securities initiated coverage of Hewlett-Packard with an "overweight" ("buy" in everyday language) rating. More meaningfully, Bank of America upgraded the stock from "neutral" to "buy," citing five factors:

(1) closing the P/E multiple gap on peers (LXK, IBM, STX, WDC, XRX, BRCD);

(2) stable-to-slightly increasing EPS revisions, as the turnaround/restructuring progresses;

(3) strong free cash flow (FCF) generation (15% yield);

(4) commitment to shareholder returns of 50% of FCF in dividend and buyback; and

(5) poor Street/investor sentiment.

... before concluding:

While we acknowledge secular growth challenges, we are impressed with the transformation progress and believe the risk/reward is favorable at 7.8x our C2014E EPS.

I've been impressed with HP's transformation, too, and I'll admit that I was wrong at the beginning of last year -- Hewlett-Pacard's stock nearly doubled in 2013. I don't disagree with any of the arguments B of A makes to support its "buy" recommendation, either -- nevertheless, I simply think there are easier ways for individual investors to make money in the stock market than by betting on turnarounds.

Best Buy(NYSE:BBY) was the worst-performing stock in the S&P 500 this week, by a wide margin, falling by more than a third (35.4%). Prompting this bloodletting was the Thursday release of the company's holiday period sales figures, which showed that Best Buy's "strategic investment" in price-competitiveness had failed: Management now estimates that the fourth-quarter operating profit margin will decline by a larger-than-expected 1.75 to 1.85 percentage points. Same-store sales during the holiday period fell 0.9%.

Like HP, Best Buy was a turnaround success story of 2013; in fact, the stock was one of the best performers in the S&P 500, rising by a stunning 237%. Both continue to face secular threats to their livelihood: For HP, it's the decline of the PC, for Best Buy, it's the ascent of e-commerce. However, HP has other businesses to fall back on, whereas for Best Buy, there is nowhere to hide. Last October, Foolish writer Adam Levine-Weinberg suggested that either Amazon.com or Best Buy will crumble. He was referring to the stocks specifically, but I think the same question may apply to the businesses -- in which case I know which company I'd favor.

If you're dead set on investing in a turnaround, I'd look at Hewlett-Packard before Best Buy.