5

So I was taking a sample scope management test online, and Question #9 stumped me -- the question on the traceability matrix. Can someone please explain why b is better than c?

Below is the direct question, quoted from the PMP Den Exam Question 3 website:

Which of the following BEST describes the purpose of a traceability matrix?

A) It describes how WBS Dictionary entries are traced to work packages, and how work packages are decomposed from deliverables

B) It’s used to make sure that all of the sub-plans of the Project Management Plan have been created

C) It helps you understand the source of each requirement, and how that requirement was verified in a later deliverable

D) It’s used to trace the source of every change, so that you can keep track of them through the entire Control Scope process and verify that the change was properly implemented

Here is their explanation for the right answer:

(b) The Requirements Traceability Matrix is a tool that you use to trace each requirement back to a specific business case, and then forward to the rest of the scope deliverables (like specific WBS work packages), as well as other parts of the project: the product design (like specific levels in Cows Gone Wild) or test strategy (like test plans that the Ranch Hand Games testers use to make sure that the game works)."

I'm not sure I understand. Can someone explain in greater detail?

  • I can't help answer your question other than to say that I've used a variety of online providers for PMP test prep and pretty much without exception they've all had a couple of questions where the answer is either debatable or is downright wrong. – Doug B Jun 3 '13 at 20:09
  • Hey Brian, welcome to PMSE! I submitted an edit to make sure the quoted material appears in a quote block and is properly attributed. Would you be able to clarify what part of the answer you specifically don't understand? I think it would help us understand your confusion if you could explain why you thought C was the correct answer. Hope this helps! :) – jmort253 Jun 4 '13 at 5:14
  • @jmort253 - I am not clear on how b is better than c. how is it accurate that requirements are related to ALL of the management plans? – Brian Jun 4 '13 at 19:44
  • The question is about a traceability matrix, not specifically a requirements traceability matrix, which makes B) more relevant than C). – The question is... Jul 28 '17 at 7:46
5

TL;DR

I probably would have picked "C" as well, but can see what they were trying to get at with their selected answer. I don't agree with it, but I can see the point. It's an academic answer that probably aligns with something in the PMBOK, but that doesn't mean it's either a great question or a great answer.

Ivory Tower Answers

Most tests, and especially most prep tests, often contain ambiguous questions or answers that are wrong from a practical perspective. This isn't necessarily a deliberate practice to hone your test-taking skills; it's often just a side-effect of having to select questions from a pool that is not allowed to precisely mirror test questions that are often protected by NDAs or copyright.

Even on the actual tests, there are often questions which are iffy because the selected answers reflect an academic (rather than practical) bent on the part of the test creators. This is a pervasive problem when the test writers are academics rather than practitioners, which is why most good tests are normed on the responses.

As a singular example, when I sat for the CISSP many years ago, I remember a particularly horrible question about virus security. The question was something along the lines of "What's the best way to prevent introduction of a virus onto a computer system?" The use of an anti-virus system was the option that any real-world security practitioner would select, but I knew that the test writers expected "certify all media" to be the correct answer for that particular test. Unless you understood that the test was written by academics who focus on abstruse government information assurance practices, you were bound to get the answer "wrong."

Potential Strategies

Unless you fail an actual exam, I wouldn't lose any sleep over questions like this. Depending on the exam, you also have a few other strategies to consider.

  1. Give the answer you think the test writers are looking for, rather than the correct answer.
  2. If your test allows it, select an answer and then comment on why you think the "correct" answer is wrong or why you think a different answer would be more correct. Especially on experimental questions that are included for norming, this can be a very effective strategy.
  3. Pick the answer you genuinely feel is correct, and rely on norming (e.g. "grading on a curve") to discount ambiguous or commonly-missed questions.

Self-Evaluation and Domain Mastery

Finally, remember that sample tests are just samples, and are rarely drawn from the actual test material. They're really just there to help you self-evaluate your confidence level in the material. Sometimes, knowing that a sample test contains invalid questions or iffy answers is as good a way to measure your domain knowledge as anything else.

By all means, if you find questions that merit additional study on your part, do that. However, sometimes it's more important to know that your answer is the one an employer would pay you to perform, regardless of what the answer key for a sample test says.

1

Maybe because C discusses only a subset of B?

Answer C indicates only two items: the source of the requirement and a link to the final deliverable.

Answer B mentions "all of the sub-plans": as they indicate in their argumentation, this also includes a link to the design, to a testplan, and so on.

Since C actually covers everything you might be able to link a requirement to, it is more complete than answer C. And therefore the 'best' answer.

My 2 cents

1

Semantic Detail

Brian, I can not tell you why 'B' is better, but I can tell you why 'C' is wrong. The reason that 'C' is not correct is due to a little "how".

"It helps you understand the source of each requirement, and how that requirement was verified in a later deliverable"

How would describe a process. The Requirements Traceability is more of a What. As in what the systems/applications functions trace back to, NOT how they were verified.

I don't think 'B' is a great answer and the explanation of it is even worse. Hope this helps.

1

The answer is B becuase you need to think what the PMBOK would say. First thing is you need to understand all the inputs and outputs of the Program Management Plan from Chapter 9 in the PMBOK. The PM plan is much more encompassing then answer C and that's what the Traceability Matrix would do. Take all the sub-plans plus requirements into consideration. I teach some the PMP sessions for the PMP exam course. It turns out HR is one item I teach.

  • Can you expand on your answer a bit? While you're clearly supporting the test answer, I'm not sure that your answer actually clarifies the reasons why the textbook answer is correct. – Todd A. Jacobs Oct 2 '13 at 14:54
0

I am not sure why B is the right answer, but I can tell how A, C, and D are not.

Option A talks about decomposition of WBS, which has nothing to do with a traceability matrix.

Option C and D, if you read between the lines, talks about "how that requirement was verified in a later deliverable" and "verify that the change was properly implemented." Now, a traceability matrix does NOT focus on verification or implementation of requirement or change. It simply helps us track the change with respect to the various parameters.

Hence, A, C, and D are clearly discarded, so, the correct answer should be B. Although, I, personally, do not appreciate B as the best answer for such question.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.