The recommendations of Wall Street analysts are often relied on by investors when deciding whether to buy, sell, or hold a stock. Media reports about these brokerage-firm-employed (or sell-side) analysts changing their ratings often affect a stock's price. Do they really matter, though?

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 Amkor Technology (AMKR).

Amkor Technology currently has an average brokerage recommendation (ABR) of 2.00, on a scale of 1 to 5 (Strong Buy to Strong Sell), calculated based on the actual recommendations (Buy, Hold, Sell, etc.) made by nine brokerage firms. An ABR of 2.00 indicates Buy.

Of the nine recommendations that derive the current ABR, four are Strong Buy and one is Buy. Strong Buy and Buy respectively account for 44.4% and 11.1% of all recommendations.

Brokerage Recommendation Trends for AMKR

Check price target & stock forecast for Amkor Technology here>>>

The ABR suggests buying Amkor Technology, 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.

Do you wonder why? As a result of the vested interest of brokerage firms in a stock they cover, their analysts tend to rate it with a strong positive bias. According to our research, brokerage firms assign five "Strong Buy" recommendations for every "Strong Sell" recommendation.

In other words, their interests aren't always aligned with retail investors, rarely indicating where the price of a stock could actually be heading. Therefore, the best use of this information could be validating your own research or an indicator that has proven to be highly successful in predicting a stock's price movement.

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.

ABR Should Not Be Confused With Zacks Rank

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.

In addition, the different Zacks Rank grades are applied proportionately to all stocks for which brokerage analysts provide current-year earnings estimates. In other words, this tool always maintains a balance among its five ranks.

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 AMKR Worth Investing In?

In terms of earnings estimate revisions for Amkor Technology, the Zacks Consensus Estimate for the current year has declined 16.9% over the past month to $1.47.

Analysts' growing pessimism over the company's earnings prospects, as indicated by strong agreement among them in revising EPS estimates lower, could be a legitimate reason for the stock to plunge 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 #4 (Sell) for Amkor Technology. You can see the complete list of today's Zacks Rank #1 (Strong Buy) stocks here >>>>

Therefore, it could be wise to take the Buy-equivalent ABR for Amkor Technology with a grain of salt.

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Amkor Technology, Inc. (AMKR) : Free Stock Analysis Report

This article originally published on Zacks Investment Research (zacks.com).

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