212 research outputs found
An Ordinal Regression Model using Dealer Satisfaction Data
This article analyses dealer satisfaction data in the agricultural technology market in Germany. The dealers could rate their suppliers in the 'overall satisfaction' and in 38 questions which can be summarized in 8 dimensions. An ordinal regression model which is also known as the proportional odds model is used to analyse the ordinal scaled rating of the dealers. The ordinal regression model is a well examined method in econometric theory, but many authors prefer using a linear regression model due to better interpretation, even the assumptions of a linear regression do not fit the data. Since the estimated coefficients of an ordinal regression model can not be properly interpreted we show other methods for a better insight of the relationship of the dealer satisfaction and the influencing variables. These methods are easy to use and it is recommended to list some of them in empirical papers.ordinal regression, dealer satisfaction, interpretation
European food quality policy: the importance of geographical indications, organic certification and food quality insurance schemes in European countries
The protection of geographical indications, organic certification and food quality assurance schemes are the cornerstones of European food quality policy. In this paper the importance of these voluntary quality policy schemes in the different Member States of the European Union is investigated. Member States may be grouped into four cluster according to the food quality orientation.food quality policy, protected geographical indications, organic certification, quality assurance schemes, Europe, cluster, PDO, PGI, TSG, Agricultural and Food Policy, Food Consumption/Nutrition/Food Safety,
An ordinal regression model using dealer satisfaction data
This article analyses dealer satisfaction data in the agricultural technology market in Germany. The dealers could rate their suppliers in the ?overall satisfaction? and in 38 questions which can be summarized in 8 dimensions. An ordinal regression model which is also known as the proportional odds model is used to analyse the ordinal scaled rating of the dealers. The ordinal regression model is a well examined method in econometric theory, but many authors prefer using a linear regression model due to better interpretation, even the assumptions of a linear regression do not fit the data. Since the estimated coefficients of an ordinal regression model can not be properly interpreted we show other methods for a better insight of the relationship of the dealer satisfaction and the influencing variables. These methods are easy to use and it is recommended to list some of them in empirical papers
Standard and Shuffled Halton sequences in a Mixed Logit Model
Modeling consumer choice in different areas has lead to an increase use
of discrete choice models. Probit or Multinomial Logit Models are often
the base of further empirical research of consumer choice. In some of these
models the equations to solve have no closed-form expression. They include
multi-dimensional integrals which can not be solved analytically.
Simulation methods have been developed to approximate a solution for
these integrals. This paper describes the Standard Halton sequence and
a modification of it, the Shuffled Halton sequence. Both are simulation
methods which can reduce computational effort compared to a random
sequence. We compare the simulation methods in their coverage of the
multi-dimensional area and in their estimation results using data of consumer
choice on grocery store formats
The Diaphanous-Related Formins: Dynamic Regulators of Smooth Muscle Cell-Specific Gene Transcription
We and others have previously shown that RhoA-dependent actin polymerization stimulates SMC-specific gene transcription by promoting the nuclear accumulation of the myocardin-related transcription factors (MRTF)-A and -B. Very little is known about the downstream RhoA effectors that mediate this response, and the goal of the studies described herein was to define the role of the diaphanous-related formins (DRFs) in regulating smooth muscle cell (SMC) differentiation. The DRFs mDia1 and mDia2 are highly expressed in cultured SMCs and in tissues containing a high smooth muscle component. Activation of mDia1 or mDia2 by RhoA stimulated actin polymerization, MRTF nuclear accumulation, and SMC-specific gene transcription. Interestingly, we found that phosphorylation of the Diaphanous Autoregulatory Domain (DAD) by Rho-kinase also stimulated mDia2 activity and SM-marker gene expression. Knockdown of mDia1/2 using siRNA significantly attenuated expression of numerous SM-marker genes in primary aortic SMCs. While we originally attributed these findings to the regulation of cytoplasmic actin dynamics by the DRFs, recent evidence linking nuclear globular (G)-actin to MRTF nuclear export led us to investigate a possible role for the DRFs in the nucleus. We found that mDia2, but not mDia1 or FHOD1, accumulated in the nucleus following treatment with leptomycin, an inhibitor of Crm-1 dependent nuclear export. Deletion and mutation analyses identified nuclear localization sequences (NLS) in the core formin homology 2 (FH2) domain and extreme N-terminus, and a leucine-rich nuclear export sequence (NES) was identified in the C-terminus of mDia2. Importantly, mDia2 variants that were excluded from the nucleus did not stimulate SMC-specific gene transcription and MRTF-B nuclear accumulation as well as wild-type mDia2. Taken together, these data support a model in which mDia2 activity in the nucleus and cytoplasm depletes cellular G-actin pools resulting in MRTF nuclear accumulation and activation of SMC-specific gene transcription
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Science and Art Teaching Practices for Oregon Elementary Teachers: Results of a Landscape Survey
An Evaluation Report for the Oregon Department of Education.
In collaboration with classroom teachers and WRAP personnel we developed and implemented a survey to collect baseline data on the science and arts teaching practices for ALL elementary teachers. This included “regular” classroom teachers (those teachers with an assigned physical classroom and set of students), art teachers, music teachers, PE teachers and other educators or administrators.
In December 2022 we recruited three (3) elementary teachers to assist us in survey development, in particular framing questions around frequency of teaching time for both arts and science instruction. One important outcome was that we formulated questions around “dedicated” teaching time where instruction was only focused on science or art content and “integrated” teaching when teachers combine science or art with other instructional areas (such as math or literacy). We also learned that there was a lot of nuances in trying to capture the science and art teaching data; for example, some schools have large blocks of time when they have a particular focus on a science content area and then equally large blocks when science teaching is replaced by instruction in other fields, such as social science. It can be difficult to reduce this instructional framework to a weekly allotment of science teaching
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Taking Stock of the STEM Beyond School Project: Accomplishments and Challenges: An Evaluation Report Prepared for the OSU Extension 4-H and Portland Metro STEM Partnership Team
The Center for Research on Lifelong STEM Learning was invited by the Oregon State University Extension Service 4-H Youth Development and the Portland Metro STEM Partnership to evaluate Year 1 of the STEM Beyond School (SBS) project. The STEM Beyond School project seeks to improve underserved youth’s access to and interest in STEM learning through: 1) the development of a statewide network of out-of-school providers focused on STEM learning opportunities, 2) building capacity of out-of-school providers to deliver effective STEM programming, and 3) delivering high dose programming to underserved youth. The Center evaluated the impact of the first year of programming on several youth outcomes (attitude towards learning, persistence in solving problems, active engagement with science, connection with and enjoyment in the program itself, and attitude toward science including whether they can succeed in science), assessed the type and quality of programming offered to youth, and analyzed the development of a state-wide network that supports out-of-school learning. As a demonstration/pilot project, the SBS project focused on collecting data that would address outcomes of the project and inform the development of a sustainable infrastructure that would support a Networked Learning Community of community-based STEM education providers.
This report draws from various data collection methods to provide insights into the development of the STEM Beyond School network and the potential impact of out-of-school programming on youth’s learner identity and associated factors which contribute to the development of interest in STEM and STEM learning. Data were collected from SBS Regional Coordinators, Program Providers, and youth participants through online and paper-based surveys; interviews with Regional Coordinators and Program Providers; and reporting workbooks and self-assessment tools completed by Program Providers
Effect of Human Disturbance on Small Mammal Communities in Itasca State Park, Minnesota
We determined effects of different levels of human disturbance on small mammal richness and relative abundance from live-trapping data obtained in Itasca State Park in northwestern Minnesota. We developed a quantitative measure of human disturbance based on disturbance units and trapped small mammals on three study sites, each reflecting a different level of disturbance. Our data revealed that small mammal diversity decreased with increasing human disturbance. Amount of ground cover and litter depth also appeared to be important in explaining differences in the demographic patterns of small mammals among sites
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