Here is the answer from PMI. I posted it as a seperate topic in this forum:

www.project-management-prepcast.com/inde...nt-of-the-pmbok#4382

Hi Guys,

Thanks for all the responses. My concern is more about getting some of us students perplexed as I recognize that hitting an exact 1.0 on CPI or SPI is almost impossible without some kind of confidence interval. Unfortunately, there are several other questions out there (and I was too lazy to write down the numbers) where they provide similar scenarios (e.g. an index that is less than .05 +- from 1.0) where the correct answer is that the project is not on budget/schedule.

I'm curious to see what PMI has to say.

:{)

Nothing new yet. As I wrote already above I will post an answer from PMI if I get one.
I wrote to customercare and do not have other contact persons. So I gues this will take some weeks due to the priority....

Sven Gruendahl wrote: Markus,
....

There must be a reason behind that and I am really curious to find out what PMI's opinon is.
Maybe I am too curious but I have send PMI a mail and just asked them.
I keep you posted!!

Cheers
Sven

Anything new yet?

btw: since every post maid herein has first to be moderated bevor publishing it, i think i am missing 2,3 posts i have made the last few days?!?
but may be, since i am active on a lot of websites/boards, that is just a wrong feeling by my owne ... ^^

Hi John -

Excellent post! As a PMP Exam Prep Trainer by trade and also a creator of questions for the OSP International PM Exam Simulator, I can offer you the following interpretation and also what I tell my PMP Exam Prep students in my live classes.

If the SPI is "greater than" 1.0, your project is "ahead of schedule"

If the SPI is "less than" 1.0, your project is behind schedule

I the SPI is "exactly" 1.0, your project is "exactly on schedule"

In my project experience if your SPI is “exactly” 1.0 then you are lying!!! (Seriously though, how often is your project "exactly on schedule"?)

And just so you know, this question was intentionally very tricky so that you understand the concepts of the SPI and what the different calculated results mean on your actual projects.

If you stick to the interpretations of the SPI calculated results outlined above when answering exam questions and on your actual real-life projects, you will understand specifically how to interpret and accurately report these results to your project stakeholders.

Thanks for a great question and entertaining forum topic!

Kevin

Kevin W. Reilly, PMP, PMI-ACP
Customer Support
OSP International LLC
Facebook PrepCast: www.facebook.com/PrepCast

Sven Gruendahl wrote:
...

But why do they print 1.0 instead of 1.000000 in the PMBOK ?
(because out of this I came to the conclusion that it must be rounding)
Why do they not just print 1?

There must be a reason behind that and I am really curious to find out what PMI's opinon is.
Maybe I am too curious but I have send PMI a mail and just asked them.
I keep you posted!!

Cheers
Sven

Hi Sven,

if i have to guess, why they didn't print just "1" in the PMBOK Guide ...hmmm, my choice would be, because the SPI also could be under "1" or "1.0" ... just like ..."0.96" .... see it?!

Regarding the "rounding theory" (that was my point, John) ... hmmm, let's just look at the example above, a SPI of "0.96".
Following the rounding theory we have to round up the SPI in this case up to "1", right?

Well, this would really not be right, right?

I am exited to read what PMI has to say about it.

Best regards,

Markus