Significance testing without truth

A popular approach to significance testing proposes to decide whether the given hypothesized statistical model is likely to be true (or false). Statistical decision theory provides a basis for this approach by requiring every significance test to make a decision about the truth of the hypothesis/model under consideration. Unfortunately, many interesting and useful models are obviously false (that is, not exactly true) even before considering any data. Fortunately, in practice a significance test need only gauge the consistency (or inconsistency) of the observed data with the assumed hypothesis/model -- without enquiring as to whether the assumption is likely to be true (or false), or whether some alternative is likely to be true (or false). In this practical formulation, a significance test rejects a hypothesis/model only if the observed data is highly improbable when calculating the probability while assuming the hypothesis being tested; the significance test only gauges whether the observed data likely invalidates the assumed hypothesis, and cannot decide that the assumption -- however unmistakably false -- is likely to be false a priori, without any data.Comment: 9 page

A method for tailoring the information content of a software process model

The framework is defined for a general method for selecting a necessary and sufficient subset of a general software life cycle's information products, to support new software development process. Procedures for characterizing problem domains in general and mapping to a tailored set of life cycle processes and products is presented. An overview of the method is shown using the following steps: (1) During the problem concept definition phase, perform standardized interviews and dialogs between developer and user, and between user and customer; (2) Generate a quality needs profile of the software to be developed, based on information gathered in step 1; (3) Translate the quality needs profile into a profile of quality criteria that must be met by the software to satisfy the quality needs; (4) Map the quality criteria to set of accepted processes and products for achieving each criterion; (5) Select the information products which match or support the accepted processes and product of step 4; and (6) Select the design methodology which produces the information products selected in step 5

A method for tailoring the information content of a software process model

The framework is defined for a general method for selecting a necessary and sufficient subset of a general software life cycle's information products, to support new software development process. Procedures for characterizing problem domains in general and mapping to a tailored set of life cycle processes and products is presented. An overview of the method is shown using the following steps: (1) During the problem concept definition phase, perform standardized interviews and dialogs between developer and user, and between user and customer; (2) Generate a quality needs profile of the software to be developed, based on information gathered in step 1; (3) Translate the quality needs profile into a profile of quality criteria that must be met by the software to satisfy the quality needs; (4) Map the quality criteria to a set of accepted processes and products for achieving each criterion; (5) select the information products which match or support the accepted processes and product of step 4; and (6) Select the design methodology which produces the information products selected in step 5

Development and validation of the teacher writing to learn scale

2014 Summer.Despite numerous efforts by educators and U.S. government agencies to improve the public education system, students continue to struggle with writing, mathematics, science and reading. Researchers and educators have employed a wide range of interventions, but proficiencies are still not at desired levels. One intervention that lacks empirical research is writing to learn (WTL). Social constructivist learning theory and cognitive learning theory of information processing provide an explanation as to why WTL promises to be an effective tool for improving content knowledge and writing skills. Further, the theoretical literature on WTL and the research on general writing mirror such theories of learning. However, despite over thirty years of theoretical and inductive research, little research examines the generalizability of WTL's effectiveness on writing and other content areas. Before measuring the effects of WTL on students, it is necessary to address teacher knowledge and efficacy of WTL. Therefore, the purpose of this proposed study is to develop an instrument to measure teacher knowledge and efficacy of WTL in the content areas of mathematics, science, social studies and language arts (which includes reading). Using the theories of self-efficacy (Bandura, 1977) and using the literature on effective teaching of writing, WTL and theories of learning. This study began with item development using the literature and teacher input. Next, experts were used to test content validity and appropriate item response. The result was a six factor model to be tested empirically. Internal consistency measures using alpha and omega, exploratory factor analysis and confirmatory factor analysis were used to check the response processes of the measure. The scale was correlated with other measures and differences tests were used to examine attributes of respondents. Results indicated problems with the first, second and last factors. The remaining two factors, perceived relevance of writing to the content and efficacy of teaching with writing showed the best fit indices, though future research is needed to refine them. The final two factors negatively correlated with writing apprehension, positively with teacher efficacy (with little explained variance) and positively correlated with number of years teaching. Difference tests indicate a strong difference between content areas of teachers on both factors and a small difference in efficacy to teach writing given gender. No differences were found between urban, rural and suburban teachers and none were found between middle school and high school teachers. This research adds to the body of work by developing a measure of teacher readiness to use WTL. However, future research is needed to refine the instrument to a usable state so that intervention research and staff development can use it

From Outside to Online: Unanticipated Directions for Utah Master Naturalist

Utah Master Naturalist is an award-winning Utah State University Extension program that promotes stewardship of Utah’s natural world through place-based, experiential field courses across the state. Although successful in eliciting positive short- and long-term impacts, Utah Master Naturalist’s traditional five-day field courses were unavailable to many students and instructors due to constraints of time and location. This case study examines Utah Master Naturalist’s first hybrid course, Desert Explorations, and describes the positive results from our pilot study, how a hybrid course solves availability issues, and how field-based learning theories can be adapted to online education through careful design

Bcl-xL-mediated remodeling of rod and cone synaptic mitochondria after postnatal lead exposure: electron microscopy, tomography and oxygen consumption.

PurposePostnatal lead exposure produces rod-selective and Bax-mediated apoptosis, decreased scotopic electroretinograms (ERGs), and scotopic and mesopic vision deficits in humans and/or experimental animals. Rod, but not cone, inner segment mitochondria were considered the primary site of action. However, photoreceptor synaptic mitochondria were not examined. Thus, our experiments investigated the structural and functional effects of environmentally relevant postnatal lead exposure on rod spherule and cone pedicle mitochondria and whether Bcl-xL overexpression provided neuroprotection.MethodsC57BL/6N mice pups were exposed to lead only during lactation via dams drinking water containing lead acetate. The blood [Pb] at weaning was 20.6±4.7 µg/dl, which decreased to the control value by 2 months. To assess synaptic mitochondrial structural differences and vulnerability to lead exposure, wild-type and transgenic mice overexpressing Bcl-xL in photoreceptors were used. Electron microscopy, three-dimensional electron tomography, and retinal and photoreceptor synaptic terminal oxygen consumption (QO(2)) studies were conducted in adult control, Bcl-xL, lead, and Bcl-xL/lead mice.ResultsThe spherule and pedicle mitochondria in lead-treated mice were swollen, and the cristae structure was markedly changed. In the lead-treated mice, the mitochondrial cristae surface area and volume (abundance: measure correlated with ATP (ATP) synthesis) were decreased in the spherules and increased in the pedicles. Pedicles also had an increased number of crista segments per volume. In the lead-treated mice, the number of segments/crista and fraction of cristae with multiple segments (branching) similarly increased in spherule and pedicle mitochondria. Lead-induced remodeling of spherule mitochondria produced smaller cristae with more branching, whereas pedicle mitochondria had larger cristae with more branching and increased crista junction (CJ) diameter. Lead decreased dark- and light-adapted photoreceptor and dark-adapted photoreceptor synaptic terminal QO(2). Bcl-xL partially blocked many of the lead-induced alterations relative to controls. However, spherules still had partially decreased abundance, whereas pedicles still had increased branching, increased crista segments per volume, and increased crista junction diameter. Moreover, photoreceptor and synaptic QO(2) were only partially recovered.ConclusionsThese findings reveal cellular and compartmental specific differences in the structure and vulnerability of rod and cone inner segment and synaptic mitochondria to postnatal lead exposure. Spherule and pedicle mitochondria in lead-exposed mice displayed complex and distinguishing patterns of cristae and matrix damage and remodeling consistent with studies showing that synaptic mitochondria are more sensitive to Ca(2+) overload, oxidative stress, and ATP loss than non-synaptic mitochondria. The lead-induced decreases in QO(2) likely resulted from the decreased spherule cristae abundance and smaller cristae, perhaps due to Bax-mediated effects as they occurred in apoptotic rod inner segments. The increase in pedicle cristae abundance and CJ diameter could have resulted from increased Drp1-mediated fission, as small mitochondrial fragments were observed. The mechanisms of Bcl-xL-mediated remodeling might occur via interaction with formation of CJ protein 1 (Fcj1), whereas the partial protection of synaptic QO(2) might result from the enhanced efficiency of energy metabolism via Bcl-xL's direct interaction with the F1F0 ATP synthase and/or regulation of cellular redox status. These lead-induced alterations in photoreceptor synaptic terminal mitochondria likely underlie the persistent scotopic and mesopic deficits in lead-exposed children, workers, and experimental animals. Our findings stress the clinical and scientific importance of examining synaptic dysfunction following injury or disease during development, and developing therapeutic treatments that prevent synaptic degeneration in retinal and neurodegenerative disorders even when apoptosis is blocked