Proctored Versus Unproctored Online Exams: Studying the Impact of Exam Environment on Student Performance

Increasing numbers of universities are offering courses in online and hybrid formats. One challenge in online assessment is the maintenance of academic integrity. We present a thorough statistical analysis to uncover differences in student performance when online exams are administered in a proctored environment (i.e., in class) versus an unproctored environment (i.e., offsite). Controlling for student grade point average (GPA), no significant differences in mean overall course performance or exam performance between the two groups were found, nor were there any differences in the mean vectors of individual exam scores. The study reveals that the group taking online exams in the unproctored environment has significantly more variation in their performance results. In examining potential causes of the greater variation, analyses were performed to assess whether an increased level of possible cheating behavior could be observed from performance results for students in the unproctored section. No evidence of cheating behavior was found

Using Van Valens Procedure In Business Research To Assess Consistent Differences In Multidimensional Variability In Two Or More Groups

Much business research involves comparisons in two or more groups on many dimensions.  This paper primarily focuses on demonstrating and providing guidance as to how researchers should approach a multivariate analysis in the comparison of sets of corresponding characteristics in two or more independent groups.  In particular, this paper demonstrates the utility of a simple but not widely known procedure developed by Van Valen (1978) that should be employed to test for the significance of differences in overall variability in the sets of corresponding characteristics in two or more groups, a test that enjoys much statistical power in detecting significant subtle group differences when the set of characteristics in one group consistently demonstrates greater variability than the corresponding set of characteristics in the other group(s).

Using Van Valens Procedure In Business Research To Assess Consistent Differences In Multidimensional Variability In Two Or More Groups

Much business research involves comparisons in two or more groups on many dimensions. This paper primarily focuses on demonstrating and providing guidance as to how researchers should approach a multivariate analysis in the comparison of sets of corresponding characteristics in two or more independent groups. In particular, this paper demonstrates the utility of a simple but not widely known procedure developed by Van Valen (1978) that should be employed to test for the significance of differences in overall variability in the sets of corresponding characteristics in two or more groups, a test that enjoys much statistical power in detecting significant subtle group differences when the set of characteristics in one group consistently demonstrates greater variability than the corresponding set of characteristics in the other group(s)

Loci influencing blood pressure identified using a cardiovascular gene-centric array

Blood pressure (BP) is a heritable determinant of risk for cardiovascular disease (CVD). To investigate genetic associations with systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP) and pulse pressure (PP), we genotyped 50 000 single-nucleotide polymorphisms (SNPs) that capture variation in 2100 candidate genes for cardiovascular phenotypes in 61 619 individuals of European ancestry from cohort studies in the USA and Europe. We identified novel associations between rs347591 and SBP (chromosome 3p25.3, in an intron of HRH1) and between rs2169137 and DBP (chromosome1q32.1 in an intron of MDM4) and between rs2014408 and SBP (chromosome 11p15 in an intron of SOX6), previously reported to be associated with MAP. We also confirmed 10 previously known loci associated with SBP, DBP, MAP or PP (ADRB1, ATP2B1, SH2B3/ATXN2, CSK, CYP17A1, FURIN, HFE, LSP1, MTHFR, SOX6) at array-wide significance (P 2.4 10(6)). We then replicated these associations in an independent set of 65 886 individuals of European ancestry. The findings from expression QTL (eQTL) analysis showed associations of SNPs in the MDM4 region with MDM4 expression. We did not find any evidence of association of the two novel SNPs in MDM4 and HRH1 with sequelae of high BP including coronary artery disease (CAD), left ventricular hypertrophy (LVH) or stroke. In summary, we identified two novel loci associated with BP and confirmed multiple previously reported associations. Our findings extend our understanding of genes involved in BP regulation, some of which may eventually provide new targets for therapeutic intervention.</p

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

Basic business statistics : concepts and applications, 11th ed./ Berenson

1013 hal.: ill, tab.; 28 cm

Basic business statistics : concepts and applications, 11th ed.[cd]/ Berenson

1013 hal.: ill, tab.; 28 cm