Shortcut to Parametric EstimationShortcut to Parametric Estimationvia Web Trnsvia Web Trns•port•port

Charles Engelke

Info Tech, Inc.

The Parametric ParadoxThe Parametric Paradox

• Parametric estimation is one of the most important and desired estimation techniques

• That very few people use

Why Don’t More People Use Why Don’t More People Use Parametric Estimation?Parametric Estimation?

• Because it requires powerful software?– No, Trns•port CES is available

What Most CES Users SeeWhat Most CES Users See

The Real ObstaclesThe Real Obstacles

• Requires lots of resources and information– The scope and breadth of issues is very large– Methodology is complex, requires a lot of training

and effort to master– A lot of fundamental data must be gathered and

managed before the first estimate can be built

• These are the big issues for CES users

Parametric Estimation is More Parametric Estimation is More Varied than Detail EstimationVaried than Detail Estimation

• The models for estimating an item price are the same regardless of the item

• Cost-based– Determine crew, productivity, materials

consumption, overhead, margin– Plug in current costs and derive unit price

• Bid-based– Calculate weighted average prices or fit to

standard formula via regression– Apply results to predict new item bid prices

Parametric Estimation Models Parametric Estimation Models Vary for Different Job TypesVary for Different Job Types

• Steps needed1. Develop conceptual model

2. Define the model as a “template” for new jobs of that type

3. Define how bid items are related to cost drivers

4. Statistically analyze historical prices

5. Enter model parameters and calculate

• Only the last two steps apply to detailed estimation with CES or Estimator

The Real CES ChallengesThe Real CES Challenges

• New CES users start with a blank screen for the parametric model templates

• Can’t develop estimates until all those preliminary definitions are done

• It’s hard to see how to specify the abstract model so it can be used for real jobs

• And there is always other, more urgent, work to be done

The Fundamental DilemmaThe Fundamental Dilemma

• CES is extremely flexible– Any parametric model that can be reduced

to formulas of any kind can be defined in it

• But the first steps are extremely steep– And it’s hard to understand these steps

without experience using other models

• The necessary flexibility and power in the system lead to barriers to entry

Simplify, simplify.Simplify, simplify.

• Parametric estimation is very complex and difficult in general

• So forget the general problem for now– All of CES will still be there to handle it

when we come back!

• Pick one type of problem, and create an “express lane” for it in CES– Make a shortcut to parametric estimation

The Shortcut(s)The Shortcut(s)

• Choose specific types of estimates to support– Asphalt resurfacing, perhaps another

• Pick one estimation model per type– That is, determine what parameters will be

considered, and how estimates will be derived from them

• Provide reasonable defaults for everything– So estimators can provide minimal data and get

adequate results, or more data for better results– Use defaults to simplify installation, too

Example: ResurfacingExample: Resurfacing

• Minimal parameters– Length, lanes, lane width, depth

• Optional parameters– Location, urban/rural, maintenance of

traffic, mobilization, milling, drainage, earthwork

• Underlying data for calculations– Acquire cost data, and classify and

analyze historical data

Shortcut Work Flow (for the user)Shortcut Work Flow (for the user)

• User enters required parameters– An estimate total is provided

• User modifies defaulted parameters– The estimate is adjusted automatically

• User wants to change basic estimation model– Must leave the shortcut and continue work

in full CES instead

Shortcut Work (for the agency)Shortcut Work (for the agency)

• Install shortcut, accept default data– Get reasonable estimates, but not based on

anything specific to your agency

• Classify basic historical data– Define a few item groups and conversions– Run analysis models to feed CES

• Develop your own models– Acquire cost driver data specific to your issues– Again, must leave shortcut for full CES at some

point

Challenges for a ShortcutChallenges for a Shortcut

• We don’t want to add it to today’s CES client– That’s already big enough– Trying to make something simple by adding to a

complex product isn’t likely to succeed

• We don’t want to create a new application– Those are expensive to build and maintain– It might be the first of many specialized

applications, which would be hard to manage

• What options are left?

Enter Web Trns•portEnter Web Trns•port

• An initiative to replace use of the Trns•port Windows clients for some functions– More ambitious than Trns•port Intranet– Not just a supplement to client-server

• Web functions are inherently very loosely coupled– So specialized functions can be developed

independently of others– Within a single manageable framework

Web Trns•port is Web Trns•port is notnot a New a New ApplicationApplication

Relatio n alDatab ase

O b jectDatab ase

Web Server

A pplicationS erver

Web Bro wser

Clien t

Only the blue pieces are new

Strategic Direction to WebStrategic Direction to Web

• Lots of reasons for Web Trns•port– (I’ll gladly harangue anyone who’ll listen)– Part of strategic plan for several years

• So Info Tech proposed a project to create needed infrastructure– And the TTF said “what’s in it for the users?”– Every project should provide direct user value

• Project redirected to start Web Trns•port to solve important user problems– Starting with parametric estimation shortcuts

Project GoalsProject Goals

• Provide a useful function almost all licensees will want to deploy– Parametric estimation shortcuts

• Be easy for licensees to implement quickly– We don’t want to deliver “shelfware”

• Ready for people to use almost immediately– Without a lot of configuration, data management,

or end-user training

• Create architectural foundation for Web Trns•port while delivering immediate value

Project in a NutshellProject in a Nutshell

• Performing this fiscal year– Late start due to redirection of goals

• Using “agile” methodologies– Replaces traditional lifecycle (with several

review and approval stages) with constant communications

– Product builds weekly or more frequently, available instantly to TRT

• Delivery Q3 2004

What We’re Shooting ForWhat We’re Shooting For

IssuesIssues

• Flexibility versus simplicity tradeoffs– Where do we draw the line?

• Integration with agency data– Can we make matching items to cost groups as

simple as the rest?

• Authorized users– Same as for similar CES screens, or a broader

group?– Allow “guest” estimators? Planners could create

rough estimates, save in CES for estimators to develop more fully later.

What Can You Do?What Can You Do?

• Communicate with the TRT– “Agile” methodologies mean more

functional decisions happen during the project

• Discuss what you want– Chat about it on the TEA mailing list

• Get your system managers ready!– A successful project will result in

something quick to install and deploy

Shortcut to Parametric EstimationShortcut to Parametric Estimationvia Web Trnsvia Web Trns•port•port

Charles Engelke

Info Tech, Inc.