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Visual Sample Plan Version 1.0 User's Guide

Description: This user's guide describes Visual Sample Plan (VSP) Version 1.0 and provides instructions for using the software. VSP selects the appropriate number and location of environmental samples to ensure that the results of statistical tests performed to provide input to environmental decisions have the required confidence and performance. VSP Version 1.0 provides sample-size equations or algorithms needed by specific statistical tests appropriate for specific environmental sampling objectives. The easy-to-use program is highly visual and graphic. VSP runs on personal computers with Microsoft Windows operating systems (95, 98, Millenium Edition, 2000, and Windows NT). Designed primarily for project managers and users without expertise in statistics, VSP is applicable to any two-dimensional geographical population to be sampled (e.g., surface soil, a defined layer of subsurface soil, building surfaces, water bodies, and other similar applications) for studies of environmental quality.
Date: April 13, 2001
Creator: Davidson, James R.; Hassig, Nancy L.; Wilson, John E. & Gilbert, Richard O.
Partner: UNT Libraries Government Documents Department

Visual Sample Plan (VSP) Models and Code Verification

Description: VSP is an easy to use, visual and graphic software tool being developed to select the right number and location of environmental samples so that the results of statistical tests performed to provide input to environmental decisions have the required confidence and performance. It is a significant help for implementing the 6th and 7th steps of the Data Quality Objectives (DQO) planning process ("Specify Tolerable Limits on Decision Errors" and "Optimize the Design for Obtaining Data," respectively).
Date: March 6, 2001
Creator: Gilbert, Richard O.; Davidson, James R.; Wilson, John E. & Pulsipher, Brent A.
Partner: UNT Libraries Government Documents Department

Petroleum Refinery Statistics: 1930

Description: From Summary: "The year 1930 marked a turning point in record-breaking performances for refining industry. From the time of the first refinery statistics of the Bureau of Mines in 1916 through 1929 the utilization of crude at refineries and the production of the principal product (motor fuel) has increased steadily. In 1930, however, the depressed conditions had a noticeable effect on motor-fuel consumption, which only increased 5 per cent over that in 1929, compared with an average annual increase for the preceding decade of 16 per cent.
Date: 1932
Creator: Hopkins, G. R.
Partner: UNT Libraries Government Documents Department

Random Sampling

Description: The purpose of this study is to show the use of random sampling in solving certain mathematical problems. The origin of random numbers to be used in sampling is discussed and methods of sampling from known distributions are then given together with an indication that the sampling procedures are unbiased.
Date: January 1957
Creator: Booker, Aaron Hicks
Partner: UNT Libraries

Internet and E-Commerce Statistics: What They Mean and Where to Find Them on the Web

Description: Statistics indicating Internet usage are imprecise. It is difficult to measure the scale of the Internet (or the World Wide Web), calculate the number and types of users (age, sex, race, gender, location, etc.), or forecast future growth. This report discusses the inherent complexities of estimating Internet and electronic commerce growth and describes various types of Internet statistics, discussing how to evaluate them and providing Web addresses for locating them. In addressing these topics, it is important to understand how the statistics are compiled, how they are used, and what their limitations are.
Date: October 24, 2000
Creator: Tehan, Rita
Partner: UNT Libraries Government Documents Department

The 2010 Decennial Census: Background and Issues

Description: The U.S. Constitution--Article 1, Section 2, clause 3, as modified by Section 2 of the Fourteenth Amendment--requires a population census every 10 years, to serve as the basis for reapportioning seats in the House of Representatives. Decennial census data also are used for within-state redistricting and in certain formulas that determine the annual distribution of more than $400 billion dollars in federal and state funds. This report discusses the major innovations that were planned for the 2010 census, problems encountered with the attempt to automate certain census field operations, the persistent differential census undercount of less advantaged groups in the population, and efforts to ensure an equitable census.
Date: May 24, 2010
Creator: Williams, Jennifer D.
Partner: UNT Libraries Government Documents Department

The 2010 Decennial Census: Background and Issues

Description: This report discusses the major innovations that were planned for the 2010 Census, problems encountered in the attempt to automate certain decennial field operations, issues of census accuracy and coverage, and efforts to ensure an equitable count.
Date: April 27, 2009
Creator: Williams, Jennifer D.
Partner: UNT Libraries Government Documents Department

The Evaluation and Control of the Changes in Basic Statistics Encountered in Grouped Data

Description: This dissertation describes the effect that the construction of frequency tables has on basic statistics computed from those frequency tables. It is directly applicable only to normally distributed data summarized by Sturges' Rule. The purpose of this research was to identify factors tending to bias sample statistics when data are summarized, and thus to allow researchers to avoid such bias. The methodology employed was a large scale simulation where 1000 replications of samples of size n = 2 ᵏ⁻¹ for 2 to 12 were drawn from a normally distributed population with a mean of zero and a standard deviation of one. A FORTRAN IV source listing is included. The report concludes that researchers should avoid the use of statistics computed from frequency tables in cases where raw data are available. Where the use of such statistics is unavoidable, the researchers can eliminate their bias by the use of empirical correction factors provided in the paper. Further research is suggested to determine the effect of summarization of data drawn from various non-normal distributions.
Date: May 1979
Creator: Scott, James P.
Partner: UNT Libraries

ASYMPTOTIC SOLUTIONS TO COMPOUND DECISION PROBLEMS

Description: A compound decision problem is the simultaneous consideration of a large number of statistical decision of identical nature. The work of Hannan and Robins are extended to the derivation of optimal asymptotic procedures in the sense of regret risk convergence for a variety of compound decision problems. Convergence theorems are derived. (D.L.C.)
Date: February 1964
Creator: Van Ryzin, J. R.
Partner: UNT Libraries Government Documents Department

Experimental Mathematics and Computational Statistics

Description: The field of statistics has long been noted for techniques to detect patterns and regularities in numerical data. In this article we explore connections between statistics and the emerging field of 'experimental mathematics'. These includes both applications of experimental mathematics in statistics, as well as statistical methods applied to computational mathematics.
Date: April 30, 2009
Creator: Bailey, David H. & Borwein, Jonathan M.
Partner: UNT Libraries Government Documents Department

Computer Routines for Probability Distributions, Random Numbers, and Related Functions

Description: Abstract: Use of previously coded and tested subroutines simplifies and speeds up program development and testing. This report presents routines that can be used to calculate various probability distributions and other functions of importance in statistical hydrology.
Date: 1983
Creator: Kirby, W. H.
Partner: UNT Libraries Government Documents Department

Suspended Sediment in Selected Streams of Southeastern Montana

Description: From purpose and scope: The purpose of this report is to summarize and evaluate fluvial-sediment data collected in the study area by the U.S. Geological Survey. The principal products of this report are sediment concentration and load statistics, sediment-transport curves, calculated mean annual sediment yields at selected stations, and an areal sediment-yield map. A secondary purpose is to describe sediment relationships between stations and basins and to identify environmental factors that are important in determining sediment yield.
Date: April 1983
Creator: Litke, David W.
Partner: UNT Libraries Government Documents Department

Congressional Statistics: Bills Introduced and Laws Enacted, 1947-2003

Description: This report is designed to fill the need for a simple tabulation of legislative workload. It provides the numbers of bills and joint resolutions introduced, and the numbers of public and private laws enacted, from the 80' Congress through the 108th Congress, first session (1947-2003).
Date: March 3, 2004
Creator: Manning, Jennifer E.
Partner: UNT Libraries Government Documents Department

The Relation Between Regression Coefficients in a Multiple-Regression Analysis

Description: In a multiple-regression analysis it is often necessary to assign a value, different from the least-squares value, to one or more of the regression coefficients. A simple method is described which eliminates the matrix algebra which, in such cases, is usually necessary in order to re-evaluate the remaining coeffcients, together with the associated variances and covariancesThe method is generalized to give an equally simple procedure for testing possible linear relations among the regression coefficients. (auth)
Date: September 1, 1959
Creator: Monahan, J. E.
Partner: UNT Libraries Government Documents Department