• by Laurie Sullivan , Staff Writer @lauriesullivan, February 1, 2016

Alphabet -- the company formerly known as Google -- releases fourth-quarter earnings Monday, the first reporting split into two segments for the company: Google, and Other Bets. That basically means its ad business and everything else.

Analysts like Piper Jaffray's Gene Munster believe investors will focus on what "Other Bets" reveal about the core profitability of the Google business when excluding the company's many other investments. "Excluding these other investments, we believe core Google EBITDA margins could be 500-800 bps higher, i.e. in the mid to high 50% range for Q4," he writes in a research note.

How lucrative is Google's core advertising business? We read bits and pieces throughout the past few weeks from the search agencies such as Adobe, Kenshoo, and IgnitionOne, among others that are supporting the advertising business.

Analysts have a good idea of what Google’s segment will look like, but last week Alphabet gave folks a cheat sheet to shed more light on Google’s sizable spending on "other" projects such as its smart-home arm Nest, and telecommunications branch Access.

The new Google segment includes internet products such as Search, Ads, Commerce, Maps, YouTube, Apps, Cloud, Android, Chrome, and Google Play as well as hardware products Google sells such as Chromecast, Chromebooks and Nexus. The technical infrastructure and newer efforts like Virtual Reality also remain in Google.

The other businesses will combine "Other Bets," which includes Access/Google Fiber, Calico, Nest, Verily (formerly Google Life Sciences), GV (formerly Google Ventures), Google Capital, X (formerly Google [X]) and other initiatives.

Raymond James Equity Analyst Aaron Kessler estimates in a research note that Alphabet will report net revenue of $16.86 billion in fourth-quarter 2015, up 16.4% from the year-ago quarter. Approximately 24% year-over-year (YoY) click growth, third-quarter 2015 YoY, and 9% YoY decline in cost per click (CPC).

Kessler expects "Other Bets" to become the key focus. "We believe investors are expecting Other Bets operating income losses of about $1.5 [billion] to $2 billion in 2015," he writes.

Overall, eMarketer estimates Google will take $45.58 billion in search ad revenue in 2016, or 55.6% of the search ad market worldwide. The analysis firm estimates Google will generate $34.11 billion in mobile Internet ad revenue worldwide, up 40.3% compared with 2015.  Mobile represents 61.1% of Google's total net ad revenue worldwide.