List Comparisons Practice

Mastering List Comparison: The “Easy” Section That Traps Everyone

Let’s be honest for a second. When you first open a study guide and see “List Comparison” questions, your first thought is probably, “Well, I don’t need to study this. I know how to read.”

It looks deceptively simple. You have two lists—List A and List B. You check them for differences. Simple, right?

Here is the trap: On the actual exam, you aren’t just checking a list. You are fighting the clock, your own eyes, and the pressure of the test environment. Whether you are aiming for the CBSA Officer Trainee Entrance Exam (OTEE) or the Public Service Entrance Exam (PSEE / GCT2), this section isn’t testing your ability to read; it is testing your Clerical Speed and Accuracy.

Why This Matters (The Real World Context)

Why do the CBSA and the Public Service Commission care about this? Because in the real world, a small “clerical error” can be a major security breach.

• For a Border Services Officer: It’s the difference between a passport number ending in 801 and 810. One is a tourist; the other might be on a watch list.

• For Public Service roles: It’s verifying financial data, coding forms, or cross-referencing massive databases where accuracy is non-negotiable.

What Are List Comparison Questions?

List comparison questions are a type of clerical speed test used in the CBSA OTEE and PSEE. They assess a candidate’s ability to quickly and accurately identify discrepancies between two sets of data, such as names, addresses, or identification numbers.

In a typical List Comparison or Clerical Checking question, you will be presented with two columns of information—names, addresses, identification numbers, or codes. Your job is to identify:

• Identical Matches: The information is exactly the same.

• Discrepancies: There is a subtle difference (a transposed number, a missing letter, or a substituted digit).

The test is designed to force your eyes to “skip” over these errors. To get a high score, you need to retrain how you look at data. Below, we’ll break down exactly why your eyes miss these details and give you the tools to stop it from happening.

Consider the 2 lists below.  The next 5 questions are based on these 2 lists.

List 1:

1. A3B7
2. C6D2
3. E4F9
4. G8H1
5. J2K5

List 2:

1. A3B8
2. C6D3
3. E4F9
4. G8H2
5. J2K6

Which item is exactly the same in both lists?

A) A3B7

B) C6D3

C) E4F9

D) J2K6

Below is a video timer with loud noise – followed by 20 questions

You have 60 seconds!   GO

Task: Compare the “Database Record” against the physical “Passport ID”. Focus: Alphanumeric strings and subtle visual substitutions.

Task: Compare the “Manifest Entry” against the “Package Label”. Focus: Names, Addresses, and Punctuation (Omissions).

• Finished in under 45 seconds?

  • Rating: Border Services Ready. You have the speed. Now check your accuracy—did you rush and miss the error in Question #15?

• Finished in 45–60 seconds?

  • Rating: Solid Contender. This is a passing pace. You are balanced and steady.

• Didn’t finish?

  • Rating: Needs Calibration. You are likely “reading” instead of “scanning.” Don’t worry—most people start here. Practice the “Trap Scan” technique to shave off those extra seconds.

Can You Beat the Clock? (20 Questions in 60 Seconds)

Set your timer for exactly 1 Minute. GO!

• Finished in under 45 seconds?

  • Rating: Border Services Ready. You have the speed. Now check your accuracy—did you rush and miss the error in Question #15?

• Finished in 45–60 seconds?

  • Rating: Solid Contender. This is a passing pace. You are balanced and steady.

• Didn’t finish?

  • Rating: Needs Calibration. You are likely “reading” instead of “scanning.” Don’t worry—most people start here. Practice the “Trap Scan” technique to shave off those extra seconds.

Anatomy of a Wrong Answer: The 3 Traps You Will Face

Not all errors are created equal. When you are staring at hundreds of list items, your brain doesn’t just “miss” things randomly; it falls into specific, predictable psychological traps.

To pass the CBSA OTEE or PSEE, you need to stop reading like a reader and start scanning like a proofreader. Here are the three distinct types of errors you need to hunt for.

1. Transposition Errors (The “Switcheroo”)

What it is: This is the most common and dangerous error in clerical tests. A transposition error occurs when two adjacent characters swap places.

• The Trap: Your brain reads in “chunks.” If you see 5-7-9-8, your brain registers the presence of those four numbers, but it often glosses over the exact order.

• The Example:

  • List A: 84920

  • List B: 84290

  • Did you catch it? The 9 and 2 switched places.

• Pro Tip: When checking long numbers (like VINs or passport numbers), read them in pairs of two. It is much harder to miss 92 vs 29 than it is to miss the whole string.

2. Omission Errors (The “Missing Link”)

What it is: An omission error happens when a single character—often a punctuation mark or a silent letter—is dropped from the second list.

• The Trap: We are trained to ignore “noise” when reading. If you see “Inc.” or “LLC”, your brain registers the concept of a company, not the specific period at the end.

• The Example:

  • List A: Applewood Logistics Inc.

  • List B: Applewood Logistics Inc

  • The Difference: The period . is missing at the end.

• Pro Tip: Pay special attention to the “tails” of data entries. The ends of sentences and abbreviations are where omissions love to hide.

3. Substitution Errors (The “Look-Alike”)

What it is: A substitution error is when a character is replaced by a visually similar one. This tests your visual acuity more than your reading speed.

• The Trap: Under stress, the eye struggles to distinguish between characters with similar shapes.

• The Example:

  • List A: K41S0N

  • List B: K4150N

  • The Difference: The letter S was replaced by the number 5.

• Common Look-Alikes:

  • O (letter) vs 0 (zero)

  • I (letter) vs 1 (one)

  • l (lowercase L) vs 1 (one)

  • B vs 8

Quick Checklist: The “Trap” Scan

Before you mark a line as “Correct,” run this 1-second mental checklist:

1. Check the Order: Did any numbers flip? (Transposition)

2. Check the Ends: Is the punctuation there? (Omission)

3. Check the Code: Is that an O or a 0? (Substitution)