Identifying Worker Characteristics Using LEHD and GIS Wendy Sisson

Topics What is LEHD? How to access LEHD data through OnTheMap LEHD and GIS Questions

Home to Work Travel Patterns One of the most important tools in transportation planning is the ability to forecast travel patterns. Through the use of origination-destination data, planners can model likely travel patterns between where commuters live and work. The trips taken to and from work usually occur during the morning and evening peak hours, when the roadways tend to be the most congested. Modeling the work commute enables planners to identify the duration and extent of roadway congestion, existing and future needs, and to identify potential multimodal transportation improvements that may be implemented to address those needs.

What is LEHD? Longitudinal Employer Household Dynamics Longitudinal Employer-Household Dynamics (LEHD) is a program offered from the U.S. Census Bureau that combines federal and state administrative data on employers and employees and refers to several online applications. The LEHD data is collected as part of censuses and surveys conducted by the Census Bureau to provide economic and demographic data as well as home-to-work travel relationships. This data can be accessed through an online mapping and reporting application, “OnTheMap”. http://lehd.did.census.govl/led/

What is LEHD? Longitudinal Employer Household Dynamics Longitudinal simply means that data is collected over time. Employer location and employment data are obtained from administrative records maintained by each state for the unemployment insurance program. Household data is obtained using data from multiple federal agencies such as Social Security and IRS. http://lehd.did.census.govl/led/

LEHD Offers 3 Key Deliverables OD employee numbers from household to place of employment Characteristics of workers by block residence Numbers of workers on each block Ages of workers Mean annual wages Characteristics of business by block Mean quarterly pay per worker Industries operating on each block (Standard Industrial Classification division) http://lehd.did.census.govl/led/library/techpapers/tp-2003-11.pdf

Problems? Confidential Data Not entire Population Potential Inaccuracies Multiple Worksite Locations Inaccurate Residence Statistical techniques and modeling are performed to create sufficient “noise” to keep the underlying workforce and employment data confidential. The output shows synthetic data that are statistically analogous to actual worker counts and locations but not exact. Since the data offered by the LEHD program is based on those covered by unemployment insurance, it does not include the retirement population, self-employed workers, cash-payment workers and some nonprofit organizations. Other potential inaccuracies include large companies with multiple locations such as a school district, may or may not provide a Multiple Worksite Report. Also, if inaccurate residence are on file, such as a student using their parent’s address. Even with the known drawbacks, the LEHD program is still a vital tool for revealing travel patterns.

One of the major advantages of the LEHD program is it’s compatibility with GIS. Analysis is performed on a selection area. This could be a pre-defined area such as a county or zip code, a hand drawn area, or imported shapefile of a selection area.

An analysis can be performed on jobs/workers living or working in the selection area. To see results about workers residing in the selection area, select HOME. To see results about workers employed in the selection area, select WORK.   The Area Profile Analysis generates results showing the location and characteristics of workers living or working in the selection area. The Area Comparison Analysis generates results showing the count and characteristics of workers employed or living in locations contained by the selection area. The “Areas to Compare:” dropdown determines the type of locations to be compared. The Distance/Direction Analysis generates results showing the distance and direction totals between residence and employment locations for workers employed or living in the selection area. The Inflow/Outflow Analysis generates results showing the count and characteristics of worker flows in to, out of, and within the selection area. All jobs: All public and private-sector jobs. Primary Jobs: Public and private-sector jobs, one job per workers. A primary job is the highest paying job for an individual worker. Private Jobs: All private-sector jobs. Private Primary Jobs: Private-sector jobs, one job per workers. A primary job is the highest paying job for an individual worker.

Today I am going to focus on what OnTheMap calls Inflow/Outflow and Distance/Direction.

Inflow/Outflow

Distance/Direction Tools With the Distance/Direction Analysis Type, we can find where people work who live in the selection area by setting the area to “Home.” Or, if we set the area to “work,” we can find where people live who work in the selection area.

Distance/Direction

Export Results Once the analysis is performed, The On The Map application offers its own mapping display and generated reports, but as GIS professionals, we like to have complete control of the look of the map, or better yet, use the data to perform our own analysis. This can be done by Exporting Geography to a shapefile.

LEHD Project Application This project on I-95 involved implementing 95 Express Toll Lanes in Broward and Palm Beach Counties. Our job was to find the appropriate access locations to enter and exit the toll lanes. It is important to place the access locations strategically so the toll lanes will be utilized. Therefore, we needed to know what interchanges people were using to enter the freeway and where they were exiting. These trip pairs are called Origins and Destinations, or O-D Pairs. Typically, O-D pairs are found using a survey. This could be a mailout survey, a roadside survey, or a license plate matching activity with video cameras. These surveys can be timely, costly, and difficult to obtain adequate representation of the traffic. Since Home to Work trips are the most frequent Origin-Destination pairs, we can use the LEHD information. In order to use LEHD to find these origin-destination pairs, some assumptions had to be made regarding the selection areas. For this project, we buffered the interstate by 2 miles and divided the buffer half-way between each interchange, thus assuming that people who live or work within each of the 39 interchange areas will use that interchange to access the highway.

LEHD Selection Areas For this project, we buffered the interstate by 2 miles and divided the buffer half-way between each interchange, thus assuming that people who live or work within each of the 39 interchange areas will use that interchange to access the highway.

GIS Application All People who Work in the Where do they live? Oakland Park Blvd Area How Many Live in Sample Rd Area? Where do they live? For this project, we buffered the interstate by 2 miles and divided the buffer half-way between each interchange, thus assuming that people who live or work within each of the 39 interchange areas will use that interchange to access the highway.

Origin-Destination Connection GIS to find O – D Pairs Origin-Destination Connection Between Sample Rd & Oakland Park Blvd Repeat Process for all 39 Interchanges!

Origin – Destination Matrix

Display Results

Display Results Enter Toll Lanes Exit Toll Lanes

Conclusion LEHD is a resource for Home – Work Travel Patterns GIS enables additional analysis and mapping capabilities LEHD with GIS is an inexpensive and efficient way to find travel patterns

Questions? Wendy.Sisson@rsandh.com

Thank You!