Browsing by Subject "Instrument development"
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Item Development and psychometric exploration of the online teaching self-efficacy scale.(Texas Tech University, 2009-05) Gosselin, Kevin Patrick; Burley, Hansel E.; Paton, Valerie O.; Siwatu, Kamau O.; Hamman, DouglasABSTRACT With over 3.1 million students enrolling in at least one online higher education course in the fall semester of 2005, online education is emerging as one of the most prominent and pervasive forms of distance education (Allen & Seaman, 2006). The resulting implication for postsecondary institutions is that the necessary instructors are needed to meet the growth of online education. The challenge presented with this need revolves around the consideration of the integral pedagogical foundations involved in online instruction. The literature presents a potential link between the ambiguity of online pedagogy and instructors� self-beliefs to teach online (Easton, 2003). However, a measure to assess the specific dimensions of online teachers� self-efficacy beliefs is not available. Additionally, current teacher self-efficacy scales do not encompass the domain specific tasks of online instruction. The study had two primary purposes; the first was to develop the Online Teaching Self-Efficacy Inventory, a series of five scales to examine the teaching self-efficacy beliefs of online instructors. The second portion of the study explored the psychometric properties of the inventory scales. The key research questions were these: (1) How many factors are needed to summarize the pattern of correlations in the correlation matrices for the inventory scales? (2) Are the inventory scales reliable? (3) Within the inventory scales, how much variance does each factor account for? (4) How can the factors be interpreted from the derived variables of the Online Teaching Self-Efficacy Inventory scales? An exploratory factor analysis for each of the five online teaching self-efficacy inventory scales was conducted to ascertain item composition using factor extraction and factor rotation analyses. The analyses resulted in identifying items for each scale whose removal enhanced the instrument�s factor structure. The resulting inventory has 47 items allocated to five scales:(1) Web-Based Course Structure;(2) The Online Alignment of Objectives, Instruction, and Assessment;(3) Course Content Migration; (4) Virtual Interaction; and (5) Selection of Technological Resources. Internal consistency and reliability analyses were conducted to determine the extent to which items within each scale measured the same construct as other items within that scale. All of the retained items corresponding with each of the five inventory scales had factor loadings of at least 0.32. The alpha reliability coefficient for each scale ranged from 0.84 to 0.95. The development of the Online Teaching Self-Efficacy Inventory relied extensively on literature pertaining to online instruction and expert content validation techniques. It treats online instruction and associated instructional self-efficacy beliefs as distinctive entities encompassed by task-specific competencies and dimensions. The results of the study provide an initial measure for examining the self-efficacy beliefs of online instructors. Implications of the study and directions for future research are presented.Item Development of a multiple-pass Raman spectrometer for flame diagnostics(2013-05) KC, Utsav; Varghese, Philip L.A multiple-pass cell is developed and applied to enhance the Raman signal from methane-air flames for temperature measurements. Stable operation of the cell was demonstrated and studied in two alignment modes. In the ring mode, the beams are focused into a ring of ~ 3 mm diameter at the center of the cell, and spectra were recorded at low dispersion (0.26 nm/pixel). Temperature is calculated from the ratio of the intensity of Stokes to anti-Stokes signal from nitrogen. Temperature is also inferred from the shapes of the Stokes and anti-Stokes peaks in the spectrum. The uncertainty in the value of flame temperature in these measurements was ±50 K. The signal gain from 100 passes is a factor of 83. Signal to noise ratio (SNR) improved by a factor of 9.3 in room temperature air with an even higher factor in flames. The improvement in SNR depends on the acquisition time and is best for short acquisition times. In the two point mode, multi passing is achieved simultaneously with high spatial resolution as the laser is focused at two small regions separated by ~ 2 mm at the center of the cell. The probe regions are 300 [mu]m × 200 [mu]m. The vast improvement in the spatial resolution is achieved at the cost of a reduced number of passes and signal gain. The two point mode is operated with 25 passes at each point with a signal gain factor of ~20; the SNR gain depends on the data acquisition time. Spectra were recorded at high dispersion (~0.03 nm/pixel). Temperature is inferred from curve fitting to the high resolution Stokes spectrum of nitrogen in methane-air flames. The curve fit is based on very detailed simulation of Raman spectrum of nitrogen. The final model includes the angular dependence of Raman scattering, electrical and mechanical anharmonicity in the polarizability matrix elements, and the presence of a rare isotope of nitrogen in air. The uncertainty in the value of temperature in the least noisy data is ±9 K. The sources of uncertainty in temperature and their contribution to the total uncertainty are also identified.Item Do I stay or do I go? A mixed-methods study of factors of attrition as reported by leavers of secondary agriculture programs(2013-05) Lemons, Laura L.; Brashears, Michael T.; Burris, Scott; Meyers, Courtney; Price, Margaret A.Agricultural education has experienced a perpetual shortage of qualified agriculture teachers in secondary classrooms for decades. Teacher attrition has been identified as a contributing factor. This two-phase exploratory mixed-methods study sought to deepen the knowledge base regarding secondary agriculture teacher attrition. The first phase of this study was a qualitative case study. Semi-structured interviews were conducted with former secondary agriculture teachers in order to describe how they characterized their experience teaching agriculture and determine the reasons they perceived for exiting the profession. Data from the interviews was analyzed and used to develop an attrition risk assessment instrument, which was pilot tested to establish validity and reliability during the second phase of the study.