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[Letter from Campbell B. Read to Station Manager of KVTT-FM 91.7, "Request for Equal Time" - May 14, 1983]

Description: Letter from Campbell B. Read, Ph.D. to the Station Manager of the Christian radio station KVTT 91.7 FM in Dallas. Dr. Read is requesting equal time to respond to certain claims made by Dr. Paul Cameron, Dr. Clem Mueller, and a vice officer of the Dallas Police Department on the "Point of View" talk radio program on May 13, 1983. The topic of the talk show was the health aspects of homosexual behavior. Read writes that the Federal Communications Commission requires that radio stations give equal time for rebuttal if "questionable, if not slanderous, statements are made about [minority] groups". Read, who holds a Ph. D. in Statistics, challenges the claims made by the guests on the talk show and claims that their comments about the gay community were indeed slanderous.
Date: May 14, 1983
Creator: Read, Campbell B.
Item Type: Letter
Partner: UNT Libraries Special Collections

The Fixed v. Variable Sampling Interval Shewhart X-Bar Control Chart in the Presence of Positively Autocorrelated Data

Description: This study uses simulation to examine differences between fixed sampling interval (FSI) and variable sampling interval (VSI) Shewhart X-bar control charts for processes that produce positively autocorrelated data. The influence of sample size (1 and 5), autocorrelation parameter, shift in process mean, and length of time between samples is investigated by comparing average time (ATS) and average number of samples (ANSS) to produce an out of control signal for FSI and VSI Shewhart X-bar charts. These comparisons are conducted in two ways: control chart limits pre-set at ±3σ_x / √n and limits computed from the sampling process. Proper interpretation of the Shewhart X-bar chart requires the assumption that observations are statistically independent; however, process data are often autocorrelated over time. Results of this study indicate that increasing the time between samples decreases the effect of positive autocorrelation between samples. Thus, with sufficient time between samples the assumption of independence is essentially not violated. Samples of size 5 produce a faster signal than samples of size 1 with both the FSI and VSI Shewhart X-bar chart when positive autocorrelation is present. However, samples of size 5 require the same time when the data are independent, indicating that this effect is a result of autocorrelation. This research determined that the VSI Shewhart X-bar chart signals increasingly faster than the corresponding FSI chart as the shift in the process mean increases. If the process is likely to exhibit a large shift in the mean, then the VSI technique is recommended. But the faster signaling time of the VSI chart is undesirable when the process is operating on target. However, if the control limits are estimated from process samples, results show that when the process is in control the ARL for the FSI and the ANSS for the VSI are approximately the same, and ...
Date: May 1993
Creator: Harvey, Martha M. (Martha Mattern)
Partner: UNT Libraries

U.S. Census Bureau: The 2011 Statistical Abstract

Description: This website contains the social, political, and economic statistical summaries for the United States, compiled from the Census Bureau, Bureau of Labor Statistics, Bureau of Economic Analysis, as well as other federal agencies and private organizations.
Date: January 2011
Creator: United States. Bureau of the Census.
Item Type: Website
Partner: UNT Libraries Government Documents Department

The Generalization of the Logistic Discriminant Function Analysis and Mantel Score Test Procedures to Detection of Differential Testlet Functioning

Description: Two procedures for detection of differential item functioning (DIF) for polytomous items were generalized to detection of differential testlet functioning (DTLF). The methods compared were the logistic discriminant function analysis procedure for uniform and non-uniform DTLF (LDFA-U and LDFA-N), and the Mantel score test procedure. Further analysis included comparison of results of DTLF analysis using the Mantel procedure with DIF analysis of individual testlet items using the Mantel-Haenszel (MH) procedure. Over 600 chi-squares were analyzed and compared for rejection of null hypotheses. Samples of 500, 1,000, and 2,000 were drawn by gender subgroups from the NELS:88 data set, which contains demographic and test data from over 25,000 eighth graders. Three types of testlets (totalling 29) from the NELS:88 test were analyzed for DTLF. The first type, the common passage testlet, followed the conventional testlet definition: items grouped together by a common reading passage, figure, or graph. The other two types were based upon common content and common process. as outlined in the NELS test specification.
Date: August 1994
Creator: Kinard, Mary E.
Partner: UNT Libraries

Ozone Pollution of Shale Gas Activities in North Texas

Description: The effect of shale gas activities on ground-level ozone pollution in the Dallas-Fort Worth area is studied in detail here. Ozone is a highly reactive species with harmful effects on human and environment. Shale gas development, or fracking, involves activities such as hydraulic fracturing, drilling, fluid mixing, and trucks idling that are sources of nitrogen oxides (NOX) and volatile organic compounds (VOC), two of the most important precursors of ozone. In this study two independent approaches have been applied in evaluating the influences on ozone concentrations. In the first approach, the influence of meteorology were removed from ozone time series through the application of Kolmogorov-Zurbenko low-pass filter, logarithmic transformation, and subsequent multi-linear regression. Ozone measurement data were acquired from Texas Commission on Environmental Quality (TCEQ) monitoring stations for 14 years. The comparison between ozone trends in non-shale gas region and shale gas region shows increasing ozone trends at the monitoring stations in close proximity to the Barnett Shale activities. In the second approach, the CAMx photochemical model was used to assess the sensitivity of ozone to the NOX and VOC sources associated with shale oil and gas activities. Brute force method was applied on Barnett Shale and Haynesville Shale emission sources to generate four hypothetical scenarios. Ozone sensitivity analysis was performed for a future year of 2018 and it was based on the photochemical simulation that TCEQ had developed for demonstrating ozone attainment under the State Implementation Plan (SIP). Results showed various level of ozone impact at different locations within the DFW region attributed to area and point sources of emissions in the shale region. Maximum ozone impact due to shale gas activities is expected to be in the order of several parts per billion, while lower impacts on design values were predicted. The results from the photochemical modeling can ...
Date: May 2016
Creator: Ahmadi, Mahdi
Partner: UNT Libraries

Partially Nested Randomized Controlled Trials in Education Research: A Guide to Design and Analysis

Description: A detailed guide showing the process of designing, conducting and analyzing results from Partially Nested Randomized Controlled Trials (PN-RCT) in education research. The guide includes a brief review of Individual-Level Randomized Controlled Trial (I-RCT) and Cluster Randomized Controlled Trials (C-RCT) in comparison with PN-RCT.
Date: July 2014
Creator: Lohr, Sharon
Item Type: Report
Partner: UNT Libraries Government Documents Department