The use of a decision matrix to prioritize SOR items in the boat design process

Program Evaluation and Review Technique (PERT) usually coupled with Critical Path Method (CPM) is not used for making decisions. It is used for Project Scheduling. In its simplest form, it is the Gantt Chart or milestone chart. PERT was developed from this.

 

Yes, you are right, Rx, my reasoning was that it is used to know what you should do in each moment and in what order you have to start each thing because it establishes the relations of subordination existing between different items. It also allows studying the consequences of dedicating more or less resources to a specific item. In short, it helps you decide what you can/should do and the consequences of doing it or not. But, of course, the user can act in accordance with this or not because there are always subjective elements that can make ignore the indications of the decision method

 

In my experience, this comment is exactly right! I've had many occasions to review the DM of other teams. What young, inexperienced guys tend to do is let the final number make the decision. The folks that have been around the block a few more times take the result of the DM and use it as a primary input in the decision process, but they don't always go with the highest scoring concept.

 

With all due respect to your friend, I would take exception to this statement. The decision making process is used to choose between distinctly different options or courses of action (COA), whether they exist at present or not. The key to doing this without getting bogged down in the process is to only look at aspects of the problem that are mutually exclusive. The standard we used for developing COA is to determine if they: 1) accomplish the requirement, 2) are feasible, 3) are unique. If some aspect of the COA is the same as the others or doesn't improve that COA, simply leave it out of the analysis. My point here is that it had to be FEASABLE - but it doesn't have to already exist, you just have to be able to do it.

As an example from a military application: you might have a requirement to degrade the power to a section of town by at least 75% for a minimum of 24 hours. You then set about deciding different ways of accomplishing that mission and use a DM to help choose which of the distinct courses of action is the best. This is an example of choosing between multiple non-existent options.

 

Still no practical examples of an actual decision matrix, that was used in the design of a boat ? Very poor thread without at least some, imo. It is like talking about the shape of a hull, without seeing an illustration or lines drawing of some kind. A picture is worth a thousand words, or in the case of some of the jargon-laden tyre-pumping going on here, nearer 10,000.

 

I disagree that the DS is a Quantitative Analysis. It is a Qualitative Analysis in that each reiteration is a comparison between parameters and an evaluation of which is more important. The importance is decided by the customer.

 

This thread originated in Magnus' introduction thread, now let's take a look at his work boat design thread, post #1 and #15.

Now I think this is a good example where the use of the Decision Matrix Method could be of great help to decide how much ice capability to put in the SOR, as this effects everything.

 

If you want to have something shared, then derogatory remarks about other people's contributions do not help to grow goodwill to give them a reason to share anything with you.

Complete nonsense, you simply underestimate the power of search engines, with just a few combined items I'll identify the ship, and there are many who are much better in this than me !

And besides that, to do as you suggest requires work, why should anyone do that for you ?

And if someone decides to put up that work, then at least some forum members will criticise the weights and decisions with uninformed misinterpretations and misperceptions.

And then what ?

I'll tell you what will happen, the one who has put up the work here will need months to rectify all the wrong interpretations that will go on and on, being build up out of many uninformed misperceptions and more misinterpretations.

Or this good person will have to leave all the nonsense output here on his/her name unrectified on the open web.

 

Dearie me, it just gets worse, you are telling me there are no design decision matrices to show, because it is all "secret squirrel" stuff, not buying it, in all likelihood the customer does not even have possession of said document, and it is the property of the designer, if they don't want to give away any secrets, well, best not even talk about their exploits with said matrices. And creations generated as "stock" designs have no customer involved anyway. My tip, they have no such document to show.

 

Could you mark out where was spoken about exploits that shouldn't have been named ?

 

People here have knocked up telling how valuable DM is, but asked for a practical example involving a boat.....just a mouthful of sawdust.

 

That's not an answer buddy, in response to your earlier bla.. bla.. I've asked ‘‘ Could you mark out . . . ? ’’ Don't you understand what mark out means ?

 

I understand English quite well, I merely pointed out that if the need for secrecy, either to preserve copyright, or not to reveal methods, "trade secrets", or anything else, prevents a sample of a boat decision matrix being displayed, then why even talk about them ? It just leaves any request for detail swinging in the breeze. This thread was forecast to be a dud, and thus it proved.

 

Then why not answer the question ? And substantiate your earlier claims with proof, because they're quite doubtful, certainly when you don't substantiate them !

 

I frankly have no idea what you are talking about. Maybe a misunderstanding of language.