Short, plain-English definitions of the terms that come up most often in ProPlace research, from strokes gained and each-way to conviction score and course fit.
A mismatch between where a golfer believes the putter (or club) face is aimed and where it actually points at impact. On short putts the face angle controls most of the starting line, so a small face-aim error sends an otherwise good stroke off target. Commonly misdiagnosed as a bad stroke or a misread.
A stroke added to your score for a rules infraction such as hitting a ball out of bounds, into a penalty area you cannot play from, or declaring a ball unplayable. In scoring terms it is the most expensive shot in golf, because you pay the stroke and you usually surrender position as well. Penalty strokes are the single largest avoidable cost in an amateur round, and their frequency rises sharply as handicap rises. Because strokes gained charges a shot with everything it costs you afterwards, a tee shot that ends in a penalty is penalised twice over, which is why driving accuracy dominates scoring below scratch and barely registers on tour.
Strokes gained measures a shot against the number of strokes a benchmark group of players would typically need from the same distance and lie. Beat that expectation and you gain a fraction of a stroke; fall short and you lose one. Summed across a round, it shows where scoring actually comes from rather than relying on blunt counts like fairways hit.
Approach proximity is the average distance your approach shots finish from the hole, usually grouped by the distance they were played from. It is a simple way to track approach quality without needing full strokes-gained data. Shorter proximity means more realistic birdie looks and, just as importantly, fewer awkward up-and-downs.
The start line is the direction the ball actually sets off in, before slope or curvature takes over. On putts it is governed mostly by where the face points at impact, with the stroke path playing a smaller part. Confusing a start-line problem with a green-reading problem is one of the more common ways golfers practise the wrong thing.
An each-way arrangement in golf splits a single position into two parts, one on the outright winner and one on the player finishing inside a set number of places. It is why ProPlace research focuses on the probability of a top finish rather than only on who wins, because most of the value in a full field sits in the places rather than the trophy. The number of places paid and the fraction applied to the place part are set by the market, not by us.
Place terms describe how many finishing positions count as a place and what fraction of the outright price the place part is settled at, commonly expressed as something like one fifth the odds, a set number of places. Place terms vary by field size and by event, and they change how much a top finish is worth, which is why ProPlace analysis is built around the probability of finishing inside the places for the field in front of us.
A dead heat is when two or more players tie for the last position that would otherwise pay out, and the return for that place is reduced to reflect that the position is shared. It is a normal feature of golf, where ties are common, and it is one reason a place is never quite as clean as it first looks. ProPlace reports finishing positions as they happened; how a tie is settled is a market rule, not a model output.
Course fit is how well a player's particular strengths match what a specific course rewards, for example long hitters on a long course with soft greens, or precise iron players on a tight and penal layout. It is one of the eight weighted factors in the ProPlace model, and it is often where the data disagrees most with the obvious names. Good course fit does not guarantee a result; it shifts the probability, which is all any pre-tournament research can honestly do.
The conviction score is a single number ProPlace publishes for each ranked player that summarises how strongly the underlying factors agree. A high conviction score means most of the signals, strokes gained, course history, recent form, course fit and the rest, are pointing the same way; a low score means they are split. It describes agreement in the data, not a promise about the outcome.
Strength of field measures how hard a given tournament field is, based on how many strong players are in it and how good they are. It matters because a top finish against a stacked field is a very different achievement from the same finish in a weak one, and the model weights the field it is actually looking at. A strong field compresses everyone's chances; a weak one spreads them out.
Value, in ProPlace research, is the gap between the model's estimated probability of a top finish and the probability implied by the market consensus. When the model rates a player's chance materially higher than the market does, that gap is the signal we surface; it is a disagreement worth examining, not an instruction. Value is about mispriced probability, not about certainty.
Implied probability is the chance of an outcome expressed by a set of odds, converted back into a percentage. It is the bridge that lets ProPlace compare the market's view of a player with the model's own probability on the same scale. Reading odds as a probability is the first step in seeing where the market and the data disagree.
More reading on the research blog.