Guessing on the SAT May 31, 2010Posted by Jason McDonald in : SAT tips , trackback
Not everyone should guess on the SAT. In fact, most people shouldn’t. Decide for yourself before test day if you should guess or not.
The majority of test takers have heard there’s a “guessing penalty” on the SAT. This is a partial truth. While the computer grading system has no way of knowing which answers were guesses, it does subtract a fraction of a point for wrong answers.
Many major test prep companies encourage guessing on SAT questions if one or more answers can be ruled out. See table below for a sample of this oversimplified logic. Their logic states that statistically, in the long run, scores will increase with “educated guessing” because the points received for correct guesses are greater than the fractions lost for those missed. This logic is flawed for most guessers for three reasons:
- It assumes the ruled out answers are, in fact, incorrect. If test takers fall for one of the many SAT traps to determine an answer looks wrong, they’re out of luck no matter how much guessing karma they have! Read myth #3 to see an example of how uninformed test takers can rule out the correct answer.
- If the guesser correctly rules out one or more answers, (s)he is likely to choose the final answer based on what looks right (This is not random guessing!) That’s right, the test writers have laid traps with answers that look right and they’ve included questions with correct answers that look wrong.
- Even if the guesser correctly rules out one or more answers, and randomly chooses one of the remaining answers, (s)he is not likely to do this enough on a single test for the statistics to reliably play out (ever heard of too small a sample size?). Everyone knows that landing heads on a fair toss has a probability of 50%. Does that mean it will definitely land heads 2 out of 4 times? 5 out of 10? No way! It’s not unusual to land heads (or tails) more than 7 out of 10 times. This same principle applies to your guessing on a handful of questions. You may not have only wasted valuable time coming up with those guesses, but you may very well have lost points on the five or ten questions in which you guessed.
|Rule out before guessing||Likely correct answer points||Likely incorrect answer points||Likely net increase|
|0/5||20||¼ of 80 = -20||0|
|1/5||25||¼ of 75 = -18.75||6.25|
|2/5||33||¼ of 66 = -16.5||16.5|
|3/5||50||¼ of 50 = -12.5||37.5|
NOTE — for the above table to have any significance, the following three conditions must be met:
1. Correct answer is never ruled out
2. Guessing is truly random
3. Guesses are made for a significant number of questions (the above table was based on 100 guesses! There are only 54 in the entire math section!)
MORAL OF THE STORY
If you think you can increase your SAT score through guessing, do yourself a favor. Learn how to recognize SAT traps and where they frequently occur, as well as common mistakes made in ruling out answers. Then guess randomly from the remaining choices. I suggest choosing the same letter all the time, such as (A) or if that was ruled out, then (B) or if that was ruled out, then (C), etc.
Some people benefit from guessing in the verbal section but not the math, while others gain points from guessing in the easy portion but not the medium or difficult ones. Most test takers consistently lower their score altogether from guessing!
Don’t believe the major test prep companies, your guidance counselor or even your math teacher when it comes to guessing on the SAT. Heck, don’t even believe me and my ten years of SAT tutoring experience! Next time you take a practice test, put a mark by questions where you guessed. Score your test with and without those guesses and you tell me, should you guess on SAT math questions? I bet not.