Travel Behavior of Hispanic Immigrants in Southern California

Transcription

1 Travel Behavior of Hispanic Immigrants in Southern California - Scenario Analysis of Future Immigrants Growth from a Parcel-Based Sketch Planning Model Hsi-Hwa Hu, Simon Choi, Frank Wen Research, Analysis and Information Services Southern California Association of Governments 4th Transportation Research Board Conference on Innovations in Travel Modeling May 2, 2012

2 Acknowledgement The authors would like to thank Transportation System Information (TSI) of California Department of Transportation for supporting 2009 NHTS California add-on data. Also thanks to Mr. SungHo Ryu for the analysis on ACS data.

3 Research Objectives Analyze the patterns of transportation assimilation of Hispanic immigrants in the area of Southern California Association of Governments (SCAG). Estimate transportation impact of future growth of Hispanic immigrants in SCAG Region. 3

4 Southern California Association of Governments (SCAG) C

5 SCAG Quick Facts Ventura Los Angeles Orange San Bernardino Riverside Imperial Nation s largest Metropolitan Planning Organization (MPO) 6 counties 191 cities 18 million people 7.5 million jobs 5

6 Assimilation of Immigrants Is the process whereby immigrants gradually adapts to the customs and attitudes of the prevailing culture and customs. The longer immigrants are in the U.S., the more integrated they become, regardless of where they came from (Myers & Pitkin, 2010).

7 Transportation Assimilation of Immigrants Transportation assimilation is also observed. Travel behavior of immigrants is similar to the native born after staying long time in the U.S. More settled immigration households are more likely to own vehicles (McGuckin and Srinivasan 2003).

8 Hispanic Immigrants in Southern California Why Hispanic immigrants? Because of its large size and fast growth. In 2010, 31% of SCAG residents were foreign born. Nearly 60% of them are Hispanics. In 2035, Hispanic population is projected to increase from current 44% of regional population to 55%. Large increase in Hispanic immigrants may affect model estimation of future vehicle use and transit demand.

9 Assimilation of Hispanic Immigrants in Southern California We use ACS and 2009 NHTS to examine assimilation patterns for SCAG households Five categories of Hispanic households: Based on number of years the householder entered the U.S. 1. less than 10 years (recent immigrants) years years years or more (settled immigrants) 5. U.S. born Hispanic Other or non-hispanic households

10 Socioeconomic Characteristics Household Income and Size Average Household Income ($1,000) Recent Household Size Settled As entering longer in the U.S., settled Hispanic immigrants tend to have higher household income, and smaller household size The gap between Hispanic and non-hispanic is significant. Data: ACS

11 Socioeconomic Characteristics Aging Effect Age of Householder Aging of householders may affect travel behavior Smaller household size More retiree and less commuting Data: 2009 NHTS & ACS

12 Daily Travel Pattern Weekday Travel per Person 6.0 Daily Trips per Person* Daily Travel Distance per Person* Settled Hispanic immigrants tend to make fewer trips, but travel for longer distance per person than recent immigrants. 0.0 * Person who is 16 years old or older Data: 2009 NHTS

13 Daily Travel Pattern Modal Share 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Mode Share Settled Hispanic immigrants tend to be a driver, and less dependent on using transit and nonmotorized modes. Drivers Passengers Transit Non-Motorized Data: 2009 NHTS

14 Daily Travel Pattern Vehicle Use & Ownership % of Household without a Car 20% 15% 10% 5% About 20% of recent Hispanic immigration households have no car. 0% Cars per Household Member Cars are more available to the settled Hispanic immigrants. Data: ACS & 2009 NHTS

15 Daily Travel Pattern Weekday VMT per Person Daily VMT per Person* VMT made by settled Hispanic immigrants is greater than that by recent immigrants. 0.0 * Person who is 16 years old or older Data: 2009 NHTS & ACS

16 Commuting & Residential Characteristics % in Single Family Detached Housing % in Low Density Neighborhood Travel decision on commuting is related to the choices of residential characteristics and auto ownership. Settled Hispanic immigrants tend to live in a single-family house, and in a low-density suburb. Data: ACS & 2009 NHTS

17 Commuting & Residential Characteristics % 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Distance to Work Place Mode Share for Commuting DriveAlong Carpool Transit Non-Motorized Longer commuting distance for settled immigrants may link to their residential choice on low density suburbs and owning a car. And it is reasonable to see settled immigrants are more likely to drive a car to work. Data: 2009 NHTS & ACS

18 Summary Transportation assimilation is found for Hispanic immigrants in Southern California. However, similar travel pattern between settled Hispanic immigrants and non-hispanic may result from the assimilation of other factors such as household income, household size, or choice on residential location and housing type. To examine the real transportation assimilation, those factors need to be controlled - use SCAG HTDA model

19 SCAG HTDA Model SCAG Household Travel Demand Analysis (HTDA) Model is a parcel-based sketch planning model to estimate average household travel. Five sub-models Vehicle Ownership Model Vehicle Trip Model Daily Total Trip Model Mode Share Model Household VMT Model 19

20 HTDA Model Structure INPUT DATA Household Socioeconomic data Neighborhood Land Use Charicteristics Level of Transit Services Residence in TOD Area Regional Accessibility (by Auto and Bus) Immigration Status of Hispanic Household Householders entered in the U.S. within 9 years, years, years, 30 years+ U.S. born Mid-term Choice Short-term Choice Vehicle Trip Model (Output: % Household Making Vehicle Trips) MODELS Vehicle Ownership Model (Output: # Household Vehicles) Mode Share Model (Output: Household Mode Share) Household VMT Model (Output: Average Household VMT) Daily Trip Model (Output: # Household Daily Trips) 20

21 Model Input Socioeconomic Characteristics Household Size, Age, Working Status, Income, Housing Type Neighborhood Built Environment Land Use, Street Connectivity & Transit Service Residence in TOD Area Regional Accessibility by Auto and Transit To test the significant effect of immigration status on travel behavior, five Hispanic immigration dummy variables are added. 21

22 Model Results By controlling all major inputs, model result shows that recent Hispanic immigrants tend to use less vehicles and more transit and non-motorized modes. Observed value vs. predicted value (NHTS households). Number of Household Vehicles Household Daily VMT Observed Predicted Observed Predicted

23 Model Results Model #1 Model #2 Model #3 Model #4 Model #4 Model #5 Hhold Vehicle Vehicle Trips Hhold Daily Trips Transit Share NM Share Hhold VMT Hispanic Immigration Status HISP > < 9 yrs NS NS HISP yrs NS NS HISP yrs NS NS NS 0.39 NS HISP 30 yrs + NS NS NS HISP U.S. Born NS NS NS NS NS Recent Immigrants: Less Vehicle Use SED Significant Significant Significant Significant Significant Significant Availability of Modes HH Vehicles P P N N P Transit Use N NM Use N Neighborhood Land Use Single-Fam. Housing N N N HH Density N NS P N EMP Density N P P NS NS Diversity N Street Connectivity N N NS P Transit Access N NS P No Bus Service P Accessibility Auto Accesibility N Bus Accessibility P P J/H Ratio P N TOD Interaction TOD x HH Den N N TOD x Bus Acc. P NS P: Positive coefficient and significant at 0.1; N: Negative coefficient and significant at 0.1 More Transit and NM 23

24 Scenario Tests Hispanic households in SCAG region will increase by 1.6 million between 2008 and 2035 Different immigration policy that affects the composition of recent/settled immigrants may lead to different estimate on transit and vehicle use. Input data for three scenarios are created: 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% % Immigration of Hispanic Households Base 2035 More Immi Less Immi. Hisp US born Hisp 30+ Hisp Hisp Hisp < base case : open immigration - more recent immigrants : restricted immigration - more settled immigrants

25 Scenario Tests % of Households by Scenarios Hisp-Yr Base 2035 More Immi Less Immi. Hisp < % 4.00% 8.00% 1.00% Hisp % 8.00% 16.00% 3.00% Hisp % 9.00% 6.00% 12.00% Hisp % 10.00% 7.00% 12.00% Hisp US born 11.63% 17.00% 11.00% 20.00% Others 66.93% 52.00% 52.00% 52.00% All % % % % # of Households by Scenarios Hisp-Yr Base 2035 More Immi Less Immi. Hisp <10 161, , ,419 74,427 Hisp , ,419 1,190, ,282 Hisp , , , ,128 Hisp , , , ,128 Hisp US born 689,203 1,265, ,701 1,488,547 Others 3,964,855 3,870,222 3,870,222 3,870,222 All 5,923,973 7,442,735 7,442,735 7,442,735

26 Model Result: with Hispanic Immigrants vs. w/o Model without Hispanic variables estimates higher vehicle use and lower demand for transit and nonmotorized modes (With Hisp) 2035 (w/o Hisp) % Diff (w/o - with) HH Veh % % V Trips 78.84% 80.54% 2% Totla Trips % Auto_driver 55.14% 54.98% 0% Autp_pass 20.55% 25.11% 5% Transit 3.64% 2.01% -2% NM 18.29% 15.70% -3% Other 2.38% 2.19% 0% VMT/HH %

27 Model Results of Scenario Test Restricted immigration scenario shows higher vehicle use and lower demand for transit and non-motorized modes than the open immigration scenario Base 2035 Open 2035 Restrict HH Veh % V Trips 78.84% 77.24% 79.87% Totla Trips Auto_driver 55.14% 53.25% 56.41% Autp_pass 20.55% 20.96% 20.21% Transit 3.64% 3.95% 3.43% NM 18.29% 19.45% 17.59% Other 2.38% 2.39% 2.37% VMT/HH % From 2035 Base Case -2.4% 1.6%

28 Conclusion Similar to the assimilation of immigrants, transportation assimilation for Hispanic Immigrants is found. Model assumption for future immigration policy has important planning implication, especially to the region with many Hispanic immigrants. Future study: examine land use-transportation interaction for Hispanic immigrants.

29 Thank you! Hsi-Hwa Hu, Ph.D. Southern California Association of Governments