Multivariate Analysis in Educational Research

ABSTRACT. A numerical avalanche-prediction scheme was developed for highway applications at Kootenay Pass, British Columbia. The model features parametric discriminant analysis using Bayesian statistics to predict avalanche occurrences. Cluster techniques are then employed in discriminant space to analyze avalanche occurrences by the method of nearest neighbours. Extensive numerical testing of the model using an historical data base indicates that prediction accuracy may be 70% or better for both avalanche and non-avalanche time intervals.

show abstract

“…Tatsuoka, 1971) that the likelihood ratio of conditional probabilities P(DIG i ) relating membership in groups 1 and 2 is given by:…”

Section: Discriminant Function and Application Of Bayesian Statisticsmentioning

confidence: 99%

Numerical avalanche prediction: Kootenay Pass, British Columbia, Canada

McClung

Tweedy

1994

J. Glaciol.

View full text Add to dashboard Cite

show abstract

“…29 Tatsuoka (1971) showed that R 2 from the MLR is equal to the sum of the product of the β i and the zero-30 order (simple bivariate) correlation, r i , which are obtained as results of MLR (see Table S2). That is, R 2 = 31 This approach allows us to directly treat the R 2 in the MLR to assess the relative importance of BHC and 6 AHC, including the strength of correlation with PAN.…”

Section: 3mentioning

confidence: 97%

Importance of Biogenic Volatile Organic Compounds to Peroxyacyl Nitrates (PANs) Production in the Southeastern U.S. during SOAS 2013

Toma

Bertman

Groff

et al. 2018

Preprint

View full text Add to dashboard Cite

24Gas-phase atmospheric concentrations of PAN, PPN, and MPAN were measured at the ground using GC-25 ECD during the SOAS 2013 campaign (1 June to 15 July 2013) in Centerville, Alabama in order to study 26 biosphere-atmosphere interactions. Average levels of PAN, PPN and MPAN were 169, 5, and 9 pptv 27 respectively, and the sum accounts for an average of 15% of NO y during the daytime (10 am to 4 pm local 28 time). Higher concentrations were seen on average in air that came to the site from the urban NO x sources 29 to the north. PAN levels were the lowest observed in ground measurements over the past two decades in 30 the Southeastern U.S. Analysis of PAN/NO x indicates PAN production in this region was sensitive to NO x . 31A multiple regression analysis indicates that biogenic VOCs account for 66% of PAN formation in this 32 region of the Southeastern U.S. Comparison of this value with a 0-D model simulation of peroxyacetyl 33 radical production indicates that at least 50% of PAN formation is due to isoprene oxidation. MPAN has a 34 statistical correlation with isoprene hydroxynitrates (IN) with an average MPAN ppb /IN ppb ratio of 0.3. 35Organic aerosol mass increases with gas-phase MPAN and IN concentrations, but the mass of organic 36Atmos. Chem. Phys. Discuss., https://doi

show abstract

“…Several authors have sought a solution for the interdependency dilemma by leaving out one of the attributes from the item set, i.e., dropping one score or category (Tatsuoka 1971;Anderson et al 1975;McClean and Chissom 1986;Steenkamp et al 2001;Leeuwen and Mandabach 2002), or by using special tools i.e., the Bentler 1993/1996 (CB) method or the direct estimation (DE) method (Cheung and Chan 2002;Cheung 2004) in a confirmatory factor analysis (CFA) model. Some authors have claimed that, in practice, differences in the analyses of both ipsative and normative scores are not as big as expected (Saville and Willson 1991;Loo 1999).…”

Section: A Condensed Literature Reviewmentioning

confidence: 99%