2001 national household travel survey user's guide - NHTS Home ...

TABLE OF CONTENTS
CHAPTER I. INTRODUCTION .................................................................................... 1-1
1-A. SURVEY SPONSORS............................................................................ 1-3
1-B. PURPOSE AND SCOPE OF THE SURVEY .......................................... 1-3
1-B.1. DATA COLLECTED ..................................................................... 1-3
1-B.2. USES OF NHTS........................................................................... 1-4
1-B.3. SCOPE - WHAT THE 2001 NHTS INCLUDES ............................ 1-5
1-B.4. SCOPE - WHAT IS NOT INCLUDED........................................... 1-6
1-C. SURVEY COVERAGE............................................................................ 1-7
1-C.1. WHO IS AN ELIGIBLE PARTICIPANT ........................................ 1-7
1.C.2. WHEN WAS THE SURVEY CONDUCTED ................................. 1-8
1.C.3. WHAT TRIPS ARE INCLUDED.................................................... 1-8
1-D. COMPARABILITY WITH EARLIER NPTS DATA ................................... 1-9
1-D.1. CHANGES OVER TIME IN THE NPTS/NHTS DATA SERIES .... 1-9
1-D.2. FACTORS AFFECTING COMPARABILITY TO PREVIOUS
SURVEYS.................................................................................. 1-14
1-E. TYPICAL NHTS HOUSEHOLD ............................................................ 1-15
CHAPTER 2. SURVEY CONTENT AND INTERVIEWS ............................................... 2-1
2-A. INTERVIEW PROCESS OVERVIEW ..................................................... 2-1
2-A.1. OVERVIEW.................................................................................. 2-1
2-A.2. THREE PHASES OF DATA COLLECTION ................................. 2-1
2-B. INTERVIEW PROCESS DETAIL............................................................ 2-2
2-B.1. ADVANCE LETTER MAILING...................................................... 2-2
2-B.2. HOUSEHOLD INTERVIEW.......................................................... 2-3
2-B.3. DIARY PACKAGE MAILING AND REMINDER CALL.................. 2-5
2-B.4. PERSON INTERVIEW ................................................................. 2-6
2-B.5. ODOMETER READINGS............................................................. 2-9
2-C. NHTS CORE DATA .............................................................................. 2-11
2-C.1. HOUSEHOLD LEVEL CORE DATA .......................................... 2-12
2-C.2. PERSON LEVEL CORE DATA.................................................. 2-12
2-C.3. VEHICLE LEVEL CORE DATA.................................................. 2-13
2-C.4. TRAVEL DAY CORE DATA....................................................... 2-13
2-C.5. TRAVEL PERIOD CORE DATA................................................. 2-14
2-D. SURVEY CONTENT CHANGES IN 2001............................................. 2-15
2-D.1. THE NPTS AND ATS SURVEYS COMBINED........................... 2-15
2-D.2. ALL HOUSEHOLD MEMBERS ELIGIBLE ................................. 2-15
2-D.3. CHANGES TO THE HOUSEHOLD INTERVIEW....................... 2-16
2-D.4. CHANGES TO THE EMPLOYMENT QUESTIONS ................... 2-16
2-D.5. INTERNET USE......................................................................... 2-16
2-D.6. TRAVEL DAY CHANGES .......................................................... 2-17
2-D.7. TRAVEL PERIOD CHANGES.................................................... 2-18