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?

Let's take a look at what these Wall Street heavyweights have to say about Arista Networks (ANET) before we discuss the reliability of brokerage recommendations and how to use them to your advantage.

Arista Networks currently has an average brokerage recommendation (ABR) of 1.67, on a scale of 1 to 5 (Strong Buy to Strong Sell), calculated based on the actual recommendations (Buy, Hold, Sell, etc.) made by 20 brokerage firms. An ABR of 1.67 approximates between Strong Buy and Buy.

Of the 20 recommendations that derive the current ABR, 13 are Strong Buy and two are Buy. Strong Buy and Buy respectively account for 65% and 10% of all recommendations.

Brokerage Recommendation Trends for ANET

Check price target & stock forecast for Arista Networks here>>>

The ABR suggests buying Arista Networks, 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.

Zacks Rank, our proprietary stock rating tool with an impressive externally audited track record, categorizes stocks into five groups, ranging from Zacks Rank #1 (Strong Buy) to Zacks Rank #5 (Strong Sell), and is an effective indicator of a stock's price performance in the near future. Therefore, using the ABR to validate the Zacks Rank could be an efficient way of making a profitable investment decision.

Zacks Rank Should Not Be Confused With ABR

In spite of the fact that Zacks Rank and ABR both appear on a scale from 1 to 5, they are two completely different measures.

Broker recommendations are the sole basis for calculating the ABR, which is typically displayed in decimals (such as 1.28). The Zacks Rank, on the other hand, is a quantitative model designed to harness the power of earnings estimate revisions. It is displayed in whole numbers -- 1 to 5.

It has been and continues to be the case that analysts employed by brokerage firms are overly optimistic with their recommendations. Because of their employers' vested interests, these analysts issue more favorable ratings than their research would support, misguiding investors far more often than helping them.

In contrast, the Zacks Rank is driven by earnings estimate revisions. And near-term stock price movements are strongly correlated with trends in earnings estimate revisions, according to empirical research.

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.

Another key difference between the ABR and Zacks Rank is freshness. The ABR is not necessarily up-to-date when you look at it. But, since brokerage analysts keep revising their earnings estimates to account for a company's changing business trends, and their actions get reflected in the Zacks Rank quickly enough, it is always timely in indicating future price movements.

Is ANET Worth Investing In?

Looking at the earnings estimate revisions for Arista Networks, the Zacks Consensus Estimate for the current year has increased 0.8% over the past month to $2.46.

Analysts' growing optimism over the company's earnings prospects, as indicated by strong agreement among them in revising EPS estimates higher, could be a legitimate reason for the stock to soar 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 #2 (Buy) for Arista Networks. You can see the complete list of today's Zacks Rank #1 (Strong Buy) stocks here >>>>

Therefore, the Buy-equivalent ABR for Arista Networks may serve as a useful guide for investors.

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