Would you open this hand in 4^th seat?

1. What’s the likelihood of a plus score?

Open the bidding in 4^th seat when you think it’s likely (>50%) to result in a plus score for your side once the hand is over. Keep in mind that passing would give you a certain (=100%) nonnegative score.

2. Guideline on the determining the likelihood:

The widely accepted guideline for estimating a likely plus score in 4^th position is “rule of 15”. The guideline says add your high card points to number of spades you hold. Open the bidding when that total is as least 15, otherwise pass. This hand qualifies as a 4^th seat opener. It contains 10 HCP and 6 spades, summing to 16 “Pearson points”. Therefore, likelihood of a plus score is greater than 50% if you open the bidding.

3. Level of opening bid when likelihood is satisfied?

At what level should you open the bidding? This hand would be an easy opening bid of two spades in seats one, two, or three. But it’s emphatically not in 4^th seat! Why is that? Because it is standard practice to open at the two-level with a hand that is slightly stronger than the usual weak two maximum. “Slightly stronger” means it qualifies for a minimum one-level opening bid in 1^st or 2^nd seat. The danger if you open this hand two spades is that partner will infer you hold equivalent of a minimum opening one-level bid. Relying on that inference, partner could easily get you too high when holding limit-raise values. Bottom line: open this hand one spade in 4th seat.