Friday Mar 22, 2013

Steps to Create an OUM Estimating Model - Part 5

Welcome to Part V of the Five Part Blog Series -- “Steps to Creating an OUM Estimating Model”. 

Developing the estimating model is only part of the process.  Equally important is the testing and refinement of the estimating model.

Test and Refine the Estimating Model

Once the implementation approach is identified, the conditions for whether the individual estimating components are included, and the factors that influence the effort for the estimating components have been identified and quantified, it is time to test the results.

Testing, refining and re-testing the estimating model is an iterative process.  It is important to test many scenarios and to use top-down estimates to both validate the overall estimating result, and the distribution of effort to the phases.  Top down estimating is an effective way to identify red-flags and omissions that need to be fixed and retested.

Using OUM’s Iterative and Incremental Development Approach

Congratulations!  You have learned how to develop an OUM estimating model.  The next step is to maintain and improve the model.

 The most effective way to create an estimating model is to apply the iterative and incremental development approach.  Start simple and iterate with continuous improvement increments based on actual usage or expanded functionality.

Good luck with your estimating model development efforts!

Thursday Mar 21, 2013

Steps to Create an OUM Estimating Model - Part 4

Welcome to Part IV of the Five Part Blog Series -- “Steps to Creating an OUM Estimating Model”. 

In today’s blog, I will share with you, from my experience, the key steps in creating a reasonable, repeatable estimating model.

Steps for Developing an OUM Estimating Model

A.   Assemble the Estimating Model Development Team

As discussed, the goal of an estimating model is to estimate a scope of work yielding consistent effort for consistent scope regardless of the experience of person or people creating the estimate.  In order to achieve this goal, a team of diverse, experienced Subject Matter Experts (SMEs) must be assembled.

B.   Defining the Scope of the Estimating Model

Before you begin building an estimating model, always clearly define what is in and out of scope for the estimate.  Technology has become complex and product suites include multiple products and technologies.  Be sure to clearly define and document the scope of what you estimate, and what you do not estimate.  For example, if you are estimating integration effort for a particular product, you will need to define whether you are estimating the development of the entire integration, or simply the integration point (SOA enablement, API, etc) for your product. 

C.  Determine the Estimating Component Level

As you know, the lowest level of detail in OUM is the task level, but OUM also groups tasks into Activities.  For the purpose of a bottom up estimate, you will need to determine what level of detail you want to achieve in your estimating model – either the task level or the activity level.

While the task level estimating model provides a higher degree of accuracy, the development and maintenance effort is increased.  For the purpose of estimating, the activity level may provide the level of detail that you need. 

Once you identify the estimating component level – either the task or the activity level -- you will want to identify those OUM tasks or activities that are typically in-scope for the estimating model.   

D. Understand the Implementation Approach

You will not be successful in creating a reasonable estimate if you do not understand the implementation approach – in this case OUM.   This is one of the most important steps in creating your estimating model, especially a bottom-up estimate. 

As you identify your implementation approach, think about whether the estimating component is always needed (required) or if it is optional.  If the estimating component is optional, then think about the conditions that will trigger it to be needed. 

An estimating model will need to identify these conditions to add the optional estimating components and associated effort when the conditions are met.

E.  Determine the “standard” effort and Identify factors that influence estimate

For each estimating component regardless of whether they are required or optional, determine the “standard” effort and the conditions that increase or decrease the standard effort.  Here are a couple of approaches to doing this step: 

  • include a base number, and then ask questions to either add or subtract effort
  • Identify a range of effort for each estimating component and ask questions to help determine where in this range of effort you need to be.
  • Keep in mind that you can create a simple estimating model with each question influences the effort of one estimating component, or a more complex estimating model where multiple questions are asked to determine the effort of an estimating component, or one question influences the effort of multiple estimating components,  or both ( multiple questions are asked which influence multiple estimating components’ effort).  The correct level of complexity for an estimating model typically reveals itself during the development process.  My advice is to start simple and add complexity where and when it is needed.

This step is the most time consuming and difficult for estimating model developers to perform.  I normally see a lot of passionate discussion from the development team reflecting unique experiences and past pain!  If you experience this when developing your estimating model, then take a deep breath and know you are on the right path!

Wednesday Mar 20, 2013

Steps to Create an OUM Estimating Model - Part 3

Welcome to Part III of the Five Part Blog Series -- “Steps to Create an OUM Estimating Model”. 

Today we will explore the different types of estimating models commonly used in the industry.

Types of Estimating Models

                Bottom Up Estimating – A bottom up estimate decomposes the project down to very small components of work, for example, an Activity or a Task.   It estimates each component to arrive at the estimate for the whole.  This estimating approach is the most time consuming, but typically results in the most accurate estimate.

                Top Down EstimatingA top down estimate applies experience from similar projects to arrive at an estimated overall effort, or a distribution of effort to project phases.  For example, if you are estimating a WebCenter Portal engagement, you may create a top down estimate by reviewing past Portal projects with similar high-level requirements.  Based on this information, you may arrive at a broad estimate for the project as a whole.  You can also evaluate similar projects to understand high-level project metrics such as the % of overall effort consumed in each project phase.  This information provides a good starting point for creating an estimating model, and it can provide a key role in validating a bottom up estimate.

In this blog, I will primarily be focusing on providing tips for creating a bottom-up estimating model as this type of estimating model is generally thought to be both the most accurate, and the most difficult to create.  Although the bottom-up estimate tends to create the most accurate estimate, it is worthwhile to apply a top-down estimate as a sanity check.  This is especially useful during the testing and initial roll-out of a new estimating model.

Before we jump into the steps for creating an OUM estimating model, it is important to establish that this blog focuses on estimating effort (# days or # hours), not duration or price.  Both duration of the engagement and the price of the engagement are highly dependent how the engagement is staffed and the cost of each resource, and; therefore, highly dependent on your individual organization.

Join tomorrow’s blog as the steps for developing an OUM Estimating Model are detailed.

Tuesday Mar 19, 2013

Steps to Create an OUM Estimating Model - Part 2

Welcome to Part II of the Five Part Blog Series -- “Steps to Create an OUM Estimating Model”. 

Creating an Estimate vs. Creating an Estimating Model

First, let’s establish the difference between an estimate and an estimating model.   A one-time estimate based on one’s unique experience is NOT an estimating model.  Rather, this is an experienced based estimate.    Often this “experienced based estimate” resembles a Work-breakdown Structure (WBS) with number of hours or days filled in based on one’s experience with each task.  Although this type of estimate is slightly better than arriving at a number solely based on the high level attributes of a similar project, an experienced-based estimate is highly dependent on the experience of the person or people completing the estimate.

The goal of an estimating model is to create a repeatable model that will provide an estimate that yields the same result for the same scope of work regardless of who completes the estimate.  To accomplish this effectively, the experience of many must be incorporated into the model in such as way as that the internal thought process that one goes through to determine the effort for a particular task is decomposed into questions and answers that can be presented by the estimator model and consistent effort calculated based on the answers.   

Sounds simple so far, right??  Before we discuss the steps on how to create an estimating model, join tomorrow’s blog as we distinguish between various types of estimating models commonly found.  

Monday Mar 18, 2013

Steps to Create an OUM Estimating Model

Welcome to my 5-part series – “Steps to Create an OUM Estimating Model”


I am a methodologist.  Together with my Oracle Method colleagues, numerous hours have been spent defining method structure and developing collateral to support Oracle Services delivery.   We also facilitate the development of estimating models for a variety of technologies and applications.

Estimating models come in many shapes and sizes.   I have been exposed to different estimating tools and approaches for estimating services -- both from the legacy Oracle estimating models and acquired estimating models.   Oracle’s own internal estimating models continue to evolve as the nature of service delivery changes and as best of breed approaches are identified.

Although I cannot provide specifics of Oracle’s internal estimating models, I can provide tips that I have learned over the years that may help you build your own estimating model, specifically an Oracle Unified Method (OUM) estimating model.

Join me tomorrow as we begin to explore how to develop an OUM estimating model.


OUM Logo
The Oracle® Unified Method (OUM) is Oracle’s standards-based method that enables the entire Enterprise Information Technology (IT) lifecycle.


· Brief

· White Paper

· Customer Program Data Sheet


· OUM on Twitter

· OUM on LinkedIn


« August 2016