2010 Seat Belt Usage Survey, April 28, 2011

Surveys were taken of motor vehicle drivers’ and passengers’ seat belt usage. These surveys are before and after parts of the “Click it or Ticket” education and enforcement campaign. The whole project starts with a pre-campaign survey followed by the four-week public information, education and enforcement campaign. Finally, the postcampaign survey is taken to test the effectiveness of the education and enforcement campaign.

2009 Seat Belt Usage Survey, April 28, 2011

Surveys were taken of motor vehicle drivers’ and passengers’ seat belt usage. These surveys are before and after parts of the “Click it or Ticket” education and enforcement campaign. The whole project starts with a pre-campaign survey followed by the four-week public information, education and enforcement campaign. Finally, the postcampaign survey is taken to test the effectiveness of the education and enforcement campaign.

2011 Seat Belt Usage Survey, July 20, 2011

Surveys were taken of motor vehicle drivers’ and passengers’ seat belt usage. These surveys are before and after parts of the “Click it or Ticket” education and enforcement campaign. The whole project starts with a pre-campaign survey followed by the four-week public information, education and enforcement campaign. Finally, the postcampaign survey is taken to test the effectiveness of the education and enforcement campaign.

Iowa Seat Belt Use Survey 2012 Data Collection Methodology Report September 13, 2012

In an effort to achieve greater consistency and comparability in state‐wide seat belt use reporting, the National Highway Traffic Safety Administration (NHTSA) issued new requirements in 2011 for observing and reporting future seat belt use. The requirements included the involvement of a qualified statistician in the sampling and weighting portions of the process as well as a variety of operational details. The Iowa Governor’s Traffic Safety Bureau contracted with Iowa State University’s Survey & Behavioral Research Services (SBRS) in 2011 to develop the study design and data collection plan for the State of Iowa annual survey that would meet the new requirements of the NHTSA. A seat belt survey plan for Iowa was developed by SBRS with statistical expertise provided by Zhengyuan Zhu, Ph.D., Associate Professor of Statistics at Iowa State University. The Iowa plan was submitted to NHTSA in December of 2011 and official approval was received on March 19, 2012.

Iowa Seat Belt Use Survey 2013 Data Collection Methodology Report, September 26, 2013

In an effort to achieve greater consistency and comparability in state-wide seat belt use reporting, the National Highway Traffic Safety Administration (NHTSA) issued new requirements in 2011 for observing and reporting future seat belt use. The requirements included the involvement of a qualified statistician in the sampling and weighting portions of the process as well as a variety of operational details. The Iowa Governor’s Traffic Safety Bureau contracted with Iowa State University’s Survey & Behavioral Research Services (SBRS) in 2011 to develop the study design and data collection plan for the State of Iowa annual survey that would meet the new requirements of the NHTSA. A seat belt survey plan for Iowa was developed by SBRS with statistical expertise provided by Zhengyuan Zhu, Ph.D., Associate Professor of Statistics at Iowa State University and was approved by NHTSA on March 19, 2012.

Iowa Seat Belt Use Survey 2014 Data Collection Methodology Report, September 25, 2014

In an effort to achieve greater consistency and comparability in state-wide seat belt use reporting, the National Highway Traffic Safety Administration (NHTSA) issued new requirements in 2011 for observing and reporting future seat belt use. The requirements included the involvement of a qualified statistician in the sampling and weighting portions of the process as well as a variety of operational details. The Iowa Governor’s Traffic Safety Bureau contracted with Iowa State University’s Survey & Behavioral Research Services (SBRS) in 2011 to develop the study design and data collection plan for the State of Iowa annual survey that would meet the new requirements of the NHTSA. A seat belt survey plan for Iowa was developed by SBRS with statistical expertise provided by Zhengyuan Zhu, Ph.D., Associate Professor of Statistics at Iowa State University and was approved by NHTSA on March 19, 2012.

Iowa Seat Belt Use Survey 2015 Data Collection Methodology Report, September 9, 2015

In an effort to achieve greater consistency and comparability in state-wide seat belt use reporting, the National Highway Traffic Safety Administration (NHTSA) issued new requirements in 2011 for observing and reporting future seat belt use. The requirements included the involvement of a qualified statistician in the sampling and weighting portions of the process as well as a variety of operational details. The Iowa Governor’s Traffic Safety Bureau contracted with Iowa State University’s Survey & Behavioral Research Services (SBRS) in 2011 to develop the study design and data collection plan for the State of Iowa annual survey that would meet the new requirements of the NHTSA. A seat belt survey plan for Iowa was developed by SBRS with statistical expertise provided by Zhengyuan Zhu, Ph.D., Associate Professor of Statistics at Iowa State University and Director of the Center for Survey Statistics and Methodology. The plan was approved by NHTSA on March 19, 2012.

Concepts and Rationale for Regional Nitrogen Rate Guidelines for Corn, April 2006

Nitrogen (N) is typically one of the largest corn fertilization expenses. Nitrogen application is critical because it signifi cantly improves corn yield in many crop rotations. When choosing N rates, producers need to carefully consider both achieving most profi table economic return and advancing environmental stewardship. In 2004, university agronomists from the Corn Belt states began discussions regarding N rate use for corn production. The reasons for the discussions centered on apparent differences in methods for determining N rates across states, misperceptions regarding N rate guidelines, and concerns about application rates as corn yields have climbed to historic levels. An outcome of those discussions was an effort with the objectives to: ▪ develop N rate guidelines that could be applicable on a regional basis and ▪ identify the most profi table fertilizer N rates for corn production across the Corn Belt. This publication provides an overview of corn N fertilization in regard to rate of application, investigates concepts for determining economic application rates, and describes a suggested regional approach for developing corn N rate guidelines directly from recent research data.

Emerging Biofuels: Outlook of Effects on U.S. Grain, Oilseed, and Livestock Markets, 2007

Projections of U.S. ethanol production and its impacts on planted acreage, crop prices, livestock production and prices, trade, and retail food costs are presented under the assumption that current tax credits and trade policies are maintained. The projections were made using a multi-product, multi-country deterministic partial equilibrium model. The impacts of higher oil prices, a drought combined with an ethanol mandate, and removal of land from the Conservation Reserve Program (CRP) relative to baseline projections are also presented. The results indicate that expanded U.S. ethanol production will cause long-run crop prices to increase. In response to higher feed costs, livestock farmgate prices will increase enough to cover the feed cost increases. Retail meat, egg, and dairy prices will also increase. If oil prices are permanently $10-per-barrel higher than assumed in the baseline projections, U.S. ethanol will expand significantly. The magnitude of the expansion will depend on the future makeup of the U.S. automobile fleet. If sufficient demand for E-85 from flex-fuel vehicles is available, corn-based ethanol production is projected to increase to over 30 billion gallons per year with the higher oil prices. The direct effect of higher feed costs is that U.S. food prices would increase by a minimum of 1.1% over baseline levels. Results of a model of a 1988-type drought combined with a large mandate for continued ethanol production show sharply higher crop prices, a drop in livestock production, and higher food prices. Corn exports would drop significantly, and feed costs would rise. Wheat feed use would rise sharply. Taking additional land out of the CRP would lower crop prices in the short run. But because long-run corn prices are determined by ethanol prices and not by corn acreage, the long-run impacts on commodity prices and food prices of a smaller CRP are modest. Cellulosic ethanol from switchgrass and biodiesel from soybeans do not become economically viable in the Corn Belt under any of the scenarios. This is so because high energy costs that increase the prices of biodiesel and switchgrass ethanol also increase the price of cornbased ethanol. So long as producers can choose between soybeans for biodiesel, switchgrass for ethanol, and corn for ethanol, they will choose to grow corn. Cellulosic ethanol from corn stover does not enter into any scenario because of the high cost of collecting and transporting corn stover over the large distances required to supply a commercial-sized ethanol facility.

Iowa Comprehensive Highway Safety Plan, September 2006

In Iowa, hundreds of people die and thousands more are injured on our public roadways each year despite decades of efforts to end this su�ffering. Past safety e�efforts have resulted in Iowans bene�fiting from one of the best state roadway systems in the nation. Due to multi-agency e�efforts, Iowa has achieved 90 percent compliance with the state’s mandatory front seat belt use law, earned the nation’s second-lowest percent of alcohol involvement in fatal crashes and made safety gains in system-wide roadway design and operational improvements. Despite these ongoing e�efforts, the state’s annual average of 445 deaths and thousands of life-changing injuries is a tragic toll and an unacceptable public health epidemic in our state. To save more lives on our roadways, Iowans must be challenged to think �differently about lifesaving measures addressing young drivers, safety belts, and motorcycle helmet use and accept innovative designs such as roundabouts. Iowa must apply evidence-based strategies and create a safety culture that motivates all citizens to travel more responsibly. They must demand a lower level of tolerance for Iowa’s roadway deaths and injuries. The Iowa Comprehensive Highway Safety Plan (CHSP) engages diverse safety stakeholders and charts the course for this state, bringing to bear sound science and the power of shared community values to change the culture and achieve a standard of safer travel for our citizens. How many roadway deaths and injuries are too many? Iowa’s highway safety stakeholders believe that, “One death is one too many” and e�effective culture-changing policy and program strategies must be implemented to help reduce this death toll from an annual average of 445 to 400 by the year 2015.

Evaluation of Gap-Graded Asphalt Concrete Mixtures Part II: Statistical Design and Analysis, HR-157, 1973

This report presents the results of a comparative laboratory study between well- and gap-graded aggregates used in asphalt concrete paving mixtures. A total of 424 batches of asphalt concrete mixtures and 3, 960 Marshall and Hveem specimens were examined. The main thrust of the statistical analysis conducted in this experiment was in the calibration study and in Part I of the experiment. In the former study, the compaction procedure between the Iowa State University Lab and the Iowa Highway Commission Lab was calibrated. By an analysis of the errors associated with the measurements we were able to separate the "preparation" and "determination" errors for both laboratories as well as develop the calibration curve which describes the relationship between the compaction procedures at the two labs. In Part I, the use of a fractional factorial design in a split plot experiment in measuring the effect of several factors on asphalt concrete strength and weight was exhibited. Also, the use of half normal plotting techniques for indicating significant factors and interactions and for estimating errors in experiments with only a limited number of observations was outlined,

Improving Traffic Safety Culture in Iowa, 2011

Vehicle crashes rank among the leading causes of death in the United States. In 2006, the AAA Foundation for Traffic Safety “made a long- term commitment to address the safety culture of the United States, as it relates to traffic safety, by launching a sustained research and educational outreach initiative.” An initiative to produce a culture of safety in Iowa includes the Iowa Comprehensive Highway Safety Plan (CHSP). The Iowa CHSP “engages diverse safety stakeholders and charts the course for the state, bringing to bear sound science and the power of shared community values to change the culture and achieve a standard of safer travel for our citizens.” Despite the state’s ongoing efforts toward highway safety, an average of 445 deaths and thousands of injuries occur on Iowa’s public roads each year. As such, a need exists to revisit the concept of safety culture from a diverse, multi-disciplinary perspective in an effort to improve traffic safety. This study summarizes the best practices and effective laws in improving safety culture in the United States and abroad. Additionally, this study solicited the opinions of experts in public health, education, law enforcement, public policy, social psychology, safety advocacy, and traffic safety engineering in a bid to assess the traffic safety culture initiatives in Iowa. Recommendations for improving traffic safety culture are offered in line with the top five Iowa CHSP safety policy strategies, which are young drivers, occupant protection, motorcycle safety, traffic safety enforcement and traffic safety improvement program, as well as the eight safety program strategies outlined in the CHSP. As a result of this study, eleven high-level goals were developed, each with specific actions to support its success. The goals are: improve emergency medical services response, toughen law enforcement and prosecution, increase safety belt use, reduce speeding-related crashes, reduce alcohol-related crashes, improve commercial vehicle safety, improve motorcycle safety, improve young driver education, improve older driver safety, strengthen teenage licensing process, and reduce distracted driving.