Investors often turn to recommendations made by Wall Street analysts before making a Buy, Sell, or Hold decision about a stock. While media reports about rating changes by these brokerage-firm employed (or sell-side) analysts often affect a stock's price, do they really matter?

Before we discuss the reliability of brokerage recommendations and how to use them to your advantage, let's see what these Wall Street heavyweights think about Schlumberger (SLB).

Schlumberger currently has an average brokerage recommendation (ABR) of 1.19, on a scale of 1 to 5 (Strong Buy to Strong Sell), calculated based on the actual recommendations (Buy, Hold, Sell, etc.) made by 21 brokerage firms. An ABR of 1.19 approximates between Strong Buy and Buy.

Of the 21 recommendations that derive the current ABR, 18 are Strong Buy and two are Buy. Strong Buy and Buy respectively account for 85.7% and 9.5% of all recommendations.

Brokerage Recommendation Trends for SLB

Check price target & stock forecast for Schlumberger here>>>

The ABR suggests buying Schlumberger, but making an investment decision solely on the basis of this information might not be a good idea. According to several studies, brokerage recommendations have little to no success guiding investors to choose stocks with the most potential for price appreciation.

Are you wondering why? The vested interest of brokerage firms in a stock they cover often results in a strong positive bias of their analysts in rating it. Our research shows that for every "Strong Sell" recommendation, brokerage firms assign five "Strong Buy" recommendations.

This means that the interests of these institutions are not always aligned with those of retail investors, giving little insight into the direction of a stock's future price movement. It would therefore be best to use this information to validate your own analysis or a tool that has proven to be highly effective at predicting stock price movements.

With an impressive externally audited track record, our proprietary stock rating tool, the Zacks Rank, which classifies stocks into five groups, ranging from Zacks Rank #1 (Strong Buy) to Zacks Rank #5 (Strong Sell), is a reliable indicator of a stock's near -term price performance. So, validating the Zacks Rank with ABR could go a long way in making a profitable investment decision.

ABR Should Not Be Confused With Zacks Rank

Although both Zacks Rank and ABR are displayed in a range of 1-5, they are different measures altogether.

The ABR is calculated solely based on brokerage recommendations and is typically displayed with decimals (example: 1.28). In contrast, the Zacks Rank is a quantitative model allowing investors to harness the power of earnings estimate revisions. It is displayed in whole numbers -- 1 to 5.

Analysts employed by brokerage firms have been and continue to be overly optimistic with their recommendations. Since the ratings issued by these analysts are more favorable than their research would support because of the vested interest of their employers, they mislead investors far more often than they guide.

On the other hand, earnings estimate revisions are at the core of the Zacks Rank. And empirical research shows a strong correlation between trends in earnings estimate revisions and near-term stock price movements.

Furthermore, the different grades of the Zacks Rank are applied proportionately across all stocks for which brokerage analysts provide earnings estimates for the current year. In other words, at all times, this tool maintains a balance among the five ranks it assigns.

There is also a key difference between the ABR and Zacks Rank when it comes to freshness. When you look at the ABR, it may not be up-to-date. Nonetheless, since brokerage analysts constantly revise their earnings estimates to reflect changing business trends, and their actions get reflected in the Zacks Rank quickly enough, it is always timely in predicting future stock prices.

Is SLB Worth Investing In?

In terms of earnings estimate revisions for Schlumberger, the Zacks Consensus Estimate for the current year has remained unchanged over the past month at $3.51.

Analysts' steady views regarding the company's earnings prospects, as indicated by an unchanged consensus estimate, could be a legitimate reason for the stock to perform in line with the broader market in the near term.

The size of the recent change in the consensus estimate, along with three other factors related to earnings estimates, has resulted in a Zacks Rank #3 (Hold) for Schlumberger. You can see the complete list of today's Zacks Rank #1 (Strong Buy) stocks here >>>>

It may therefore be prudent to be a little cautious with the Buy-equivalent ABR for Schlumberger.

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