Shares of Facebook(FB) - Get Report are up over 13% year to date, helped along by last week's stellar first-quarter earnings report. Rahul Shah, CEO of Ideal Asset Management, said Wall Street analysts are still underestimating the social networking giant.

"Facebook's first quarter is usually their slowest in terms of revenue growth, so upcoming quarters will be even better, and Wall Street's expectations are still too low," said Shah.

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Menlo Park, Calif.-based Facebook posted $5.38 billion in first-quarter revenue, up 52% over the prior year. Earnings per share came in at 77 cents, compared to 42 cents the prior year. Wall Street analysts expected Facebook to deliver revenue of $5.25 billion and earnings per share of 62 cents.

Among the main drivers for Facebook was its stellar growth in advertising revenue. Advertising revenue grew nearly 60% year-over-year to $5.2 billion. Mobile advertising revenue represented about 82% of all advertising revenue for the quarter.

Shah is also bullish on FedEx(FDX) - Get Report , which is up 12.5% this year. He said the package and logistics company is a "good play on online purchasing growth" and the step-up in oil prices "won't hurt it." 

On the flip side, Shah is bearish on Norfolk Southern(NSC) - Get Report , which is down over 7% so far in 2016, despite its earnings beat last week. The railroad reported first-quarter net income of $387 million, or $1.29 per share, last week. That is up 25% from $310 million, or $1 per share, a year earlier. Analysts had on average expected earnings per share of 97 cents. Revenue in the quarter totaled $2.42 billion, above market expectations of $2.39 billion.

"Norfolk Southern still has too much exposure to coal," said Shah. Volumes are at risk of declining as the expansion reaches its final stages, he said.

Shah is also negative on Walmart(WMT) - Get Report , despite the fact that the world's largest retailer has seen its stock rise over 10% year to date.

"Walmart is being squeezed by both Amazon(AMZN) - Get Report and the dollar stores," said Shah.