FOCUS MODEL OVERVIEW Denver Regional Council of Governments June 24, 2011

This presentation  Ask Erik, Shahida and me questions throughout  General Concepts  Break model into four “stages”  Then several steps within each stage  Describe each step- it’s inputs and outputs  Review stage inputs and outputs  Move onto to next stage

General Concept 1: What is a logit model? 2 minute version  A model that calculates the utility of each choice from a set of discrete choices for a decision maker based on characteristics of the choice and the decision maker  Suppose we have a trip we know is 3 miles long, it’s purpose is to eat a meal, it’s final location is the CBD, the person who made the trip is age 68, the person’s income is $28,000/year. What is the utility for this trip for various travel modes?  We calculate the utility of taking transit for example based on the above information and the cost of transit, the time on transit, etc

General Concept 1: Logit Models  Many types: we use multinomial logit and nested logit  Outcome is a simple closed form probability (not the choice) The choice must be randomly selected using a monte carlo process.  Anything to add?  Questions?

General Concept 2: Monte Carlo Simulation  If model only assign probabilities to a choice, how do we get a choice  Monte carlo simulation  Suppose you have three choices, one with probability 0.1, one with probably 0.4 and one with probability 0.5.  Arbitarily, you assign choice one the range on the number line from 0 to 0.1 to choice one, from 0.1 to 0.5 to choice two and 0.5 to 1 to choice three.  Then you generate a pseudo-random number from 0 to 1.  If the number lands on the range assigned to the choice: you pick that choice  For example, if you generate the number , you would select choice 3

General Concept 3: Tours and Trips HOMEWORK STORE TOUR-BASED MODEL 1 home-based work tour 1 shopping stop TRIP-BASED MODEL 1 home-based work trip 1 non-home-based trip 1 home-based non work trip Outbound, Away From Home Tour Half Inbound, toward home tour half

General Concept 4: Focus Model Flow: “Four” Steps STAGE 1: Make Population And Network STAGE 2: Run GISDK to Mode Choice STAGE 3: C# Logit Models to Create Trips STAGE 4: GISDK Assignment FEEDBACK

General Concept 5: Mechanics: Code Types used in Model C# Code Logit Model Running; Model Manager GISDK Code Skimming, Assignment, I-E/E-E DIA Trips SQL Server Database Queries Data Storage Java For Population Synthesizer

General Concept 6: Use of SQL Server

Households, Persons and Points in SQL Server

Persons, Trips, and Tours in SQL Server

General Concept 7: GISDK: Old Model Socio-economic Inputs Area Type Parking Cost Network Processing & Data Preparation Highway Skimming Transit Skimming Trip Generation Trip Distribution Mode Choice Highway Assignment Transit Assignment Highway Network Inputs Transit Network Inputs Time-of-Day

General Concept 8: Why are we doing this anyway?  Data on ANY geography: all data is at a point level  Using Most Demographic Characteristics of People  Walking, biking, and transit  Vehicle Miles Traveled households in LoDo in 2035  Average Bike Miles per persons age 70+ years old in 2020  Number of Cars owned by college students attending CU Boulder in 2015  Average Distance to Work by Restaurant Workers

Review of General Concepts  1. Logit Models are models that make assign probabilities to a set of choices for an individual from a list of discrete choices.  2. The actual choice is made using a monte carlo process.  3. Travel in the model is made on a tour-level, and then a trip level.  4. We can divide the model into four stages.  5. We use four types of code in the model: T-SQL, C#, GISDK, and Java.  6. Much of the input and output data is stored in SQL Server.  7. We still have to run parts of our old GISDK code for path building, skimming and assignment.  8. We are doing this because we can get much finer detail and answer planning questions better using the model.

Thinking points before we dive into the steps  How is the new model activity-based? How is it disaggregate?  How does the model actually do all this crazy stuff?  How is the old model different than the new model?  How does the model STILL simplify actual human behavior?

Focus Model Flow: 28 Steps FEEDBACK

User Interface: How the steps look

Focus Model Flow: Stage 1 STAGE 1: Make Population And Network STAGE 2: Run GISDK to Mode Choice STAGE 3: C# Logit Models to Create Trips STAGE 4: GISDK Assignment FEEDBACK

STAGE 1: Make Population and Network  Java: Population Synthesizer  C# to process in database: Size Sum Variable Calculator; PopSyn Output Processor  GISDK called from C#: GISDK Preprocess Creating networks for example

Population Synthesizer ACS or PUMS Disaggregate Data Aggregate Data that We Need to Match: Economic Forecasts, Land Use Forecasts Disaggregate Population With the Right Portions Matching the Economic and Land Use Forecasts Questions?