This essay covers a designed experiment on paperboard where the quality under study is tear strength alongside and across. The objective is to examine what consequences the loss of balance in a designed experiment has on the explanatory power of the proposed empirical model. As did happen, the trial plan didn’t go as planned when the first run caused a disruption of the paperboard in the machine. Decision from the company was to raise the low level of one of the design factors to prevent this from happening again. The consequence of this is an alteration of the design during ongoing experimentation. This in turn affects what analysis approaches are appropriate for the problem. Three different approaches for analyzing the data are presented, each with different propositions on how to deal with the complication that occurred. The answer to the research question is that the ability of the empirical model to discover significant effects is moderately weakened by the loss of one run (out of eight total). The price payed for retrieving less information from the experiment is that the empirical model, for tear strength across, doesn’t deem the effects significant at the same level as for the candidate model with eight runs. Instead of concluding that the main effect of  and the interaction effect  is significant at the 2%- and 4%-level, respectively, we must now settle with deeming them significant at the 6%- and 7%-level.

In this study, the usability of smart phone application store app is evaluated. The study was performed on different smart phone operating systems. Data about usability was gathered through surveys and think aloud based experiment. Anova analysis was also performed on data to identify significant issues. A lot of smartphone users reported issues with installing, locating and searching about apps. Many users had issues with uninstalling of apps and navigating the search results when looking for apps. The smartphone operating system and the app store does not provide seamless navigation and alot of content is not tailored for smart phone users.

In variety testing as well as in psychological assessment, the situation occurs that in a two-way ANOVA-type model with only one replication per cell, analysis is done under the assumption of no interaction between the two factors. Tests for this situation are known only for fixed factors and normally distributed outcomes. In the following we will present five additivity tests and apply them to fixed and mixed models and to quantitative as well as to Bernoulli distributed data. We consider their performance via simulation studies with respect to the type-I-risk and power. Furthermore, two new approaches will be presented, one being a modification of Tukey's test and the other being a new experimental design to test for interactions.

SKF Coupling in Hofors manufactures screws and couplings to the energy sector and the marine industry. The products have tight tolerances to be more attractive at the market through the tolerances. With increased competition on the market, the quality requirements increase, which means that many products fail to meet the quality requirements in order to avoid customer complaints. The purpose of this work was to improve measurement accuracy. To get an overview of the current situation, interviews and observations were made. A measurement system analysis was conducted by tests where a certain number of products were measured by a certain number of operators, with a certain number of repetitions. The test results were analyzed by a two-way ANOVA and Gauge R&R, which are common methods in measurement system analysis. A cause-and-effect diagram was used to investigate the causes of quality problems. The results indicated that the existing measurement systems were not reliable enough. The shortcomings may depend on the measuring device and the operator. The measuring device may be defective or have calibration defects. Operators can have different methods when measuring which contributes to variations in the measurements. The work led to suggestions for improvements that could imply higher accuracy in the measurement systems. For example, a tighter calibration interval of the measuring device would lead to reduced impact from the measuring device. A standardized education of measurement method, measurement environment and the importance of deviation management can also lead to improved measurement accuracy. / SKF Coupling i Hofors tillverkar skruvar och kopplingar till energisektorn och den marina industrin. Produkterna har snäva toleranser för att genom toleranserna vara mer attraktiva på marknaden. I och med ökad konkurrens ökar kvalitetskraven. Därför kasseras många produkter, som inte uppnår kvalitetskraven, för att undvika returer från kunderna. Syftet med arbetet var att förbättra mätnoggrannheten. För att få en överblick av nuläget gjordes intervjuer och observationer. En mätsystemanalys gjordes genom tester där ett utvalt antal produkter mättes av ett utvalt antal operatörer, med ett visst antal upprepningar. Testresultaten analyserades med en tvåvägs-ANOVA och Gauge R&R som är vanliga metoder inom mätsystemanalys. Ett orsak-verkan-diagram användes för att undersöka orsakerna till kvalitetsproblemen. Resultatet visade att det finns brister i det nuvarande mätsystemet. Bristerna kan bland annat bero på mätdonet och operatören. Mätdonet kan exempelvis vara defekt eller ha brister i kalibreringen. Operatörerna kan ha olika metoder som bidrar till variationer i mätningarna. Arbetet ledde till förbättringsförslag, som kan innebära högre noggrannhet i mätsystemen. Exempelvis skulle ett tätare kalibreringsintervall hos mätdonen leda till minskad påverkan från mätdonen. En standardiserad utbildning av mätmetod, mätmiljö och vikten av att avvikelsehanteringen följs kan också leda till en förbättrad mätnoggrannhet.

A human brain is capable to achieve great things, to endure heavy stress and to calculate complex problems. What happens when it fails to do so? Is there anything that could be done to prevent this from happening? Is it possible to help a pilot in command manage his or her stress during flight by measuring finger temperature, skin conductance, ECG and heart rate variations? This thesis study processes that can help pilots manage high stress with simple tools such as closing their eyes and taking a few deep breaths. To determine when the calming measures are needed and to evaluate potential effects, all the signal data stated above are used combined with scoring of every participant performance. The statistical methods used involves an ANOVA-test and mean value calculations. The results were also analyzed using CBR to get a better understanding of the results and to not only rely on statistical methods. The thesis is limited to a minor study of 10 student pilots participating in two sessions with a heavy workload departure in a simulator. The test did result in a small difference between the two sessions which pointed at the calming measures giving a slight improvement for the pilots. However, when ANOVA was applied it showed that the difference between the two sessions was not a significant one. This could be due to several reasons; the pilots were not used to the calming measures and because of this felt more stressed when trying to use the calming measures as well. There might have been a difference if calming measures were included into pilot training already from the beginning. Another reason might be because this is only a minor study and the difference was not apparent on so few participants. In future research, however, there might be a breakthrough on how to handle stress in a cockpit environment involving similar sensors.

The use of Information Technology (IT) in healthcare organizations is omnipresent. The nursing curriculum needs to include IT in order to prepare nursing students to acquire Nursing Informatics (NI) competencies before entering the workplace. The literature review suggests that pre-licensure nurses are ill prepared to enter the workforce because they lack some of the essential computer skills that employers are seeking when hiring new graduates (Fetter, 2009a; Gassert, 2008; Ornes & Gassert, 2007). The lack of defined competencies in NI is a worldwide problem (Chang, 2007; Fetter, 2009b; Staggers, Gassert, & Curran, 2001; Ragneskog & Gerdner, 2006). This thesis will examine two questions: 1) Do nursing students increase their NI competency scores progressively in their school program from year 1 to 4? 2) Do nursing students with work experience requiring the use of technology outside of the curriculum get higher scores for NI competencies than those without by the end of 4th year? A questionnaire was given to 176 nursing students asking them to rate their computer use and computer knowledge. The results were consistent for both independent variables of year of study and experience with technology in the work setting. There is no interaction present between variables; they each influence individually the total score for NI competencies for nursing students. The results show NI competencies progressively increasing over the four academic years. The nursing students scored higher still when they had technology experience in any work field on NI competencies. The combination of academic and work experience that uses IT provides nursing students with more opportunities to practice and assimilate their NI competencies before graduation.

This thesis project was carried out by two students on behalf of SMA Mineral AB, which owns the lime plant in Rättvik, where there was need to establish a sampling method for the local quick lime product. The aim was to ensure a maximum concentration of impurities in the product—primarily carbon and sulphur. The mean value of sulphur found in the input material varied over time. Consequently, a suitable statistical method was needed to ensure product quality for the prospective customer as they required that the sulphur content of the proposed product never exceed 500 ppm.The aim was, on the one hand, to process and compile the sampling results in accordance with a suitable statistical method which enabled reasonable conclusions about the product quality and, on the other hand, to answer three key queries that SMA Mineral AB posed:• to investigate whether the product’s sulphur content was affected during conveyance through the lime plant;• to investigate whether sampling at various time intervals may have been a factor which affected the product’s sulphur content;• to investigate whether there was, or were, any particular times of day at which the sulphur content always maintained the correct level.A number of phases were required to find answers to these questions. The planning phase was initiated by a visit to Rättvik, with the purpose of gaining an overall picture of how work at the plant was conducted as well as which guidelines and regulations were in effect. After this visit, a project plan was drawn up in order to serve as support for further work.The sampling campaign took place during the period of 13–16 April 2015 and analysis of the collected material was carried out the following week at the company’s laboratory in Persberg, Sweden. However, the results from the sampling campaign did not provide sufficient basis for answering the company’s questions, which is why data from SMA Mineral AB’s own data collection was used. Data collected during the sampling campaign proved to follow normal distribution. Subsequently, the statistical analysis of variance method, ANOVA, was applied in order to investigate whether the sulphur content changed with respect to the time interval and the sampling site. The test results demonstrated p-values under 0.005, which meant that neither the sampling site nor the sampling time intervals had an effect on the product’s sulphur content. The company’s question, whether there were daily time intervals of acceptable sulphur content in the product, was answered with the assistance of the company’s own data collection, which demonstrated that it did not follow normal distribution. For that reason, the bootstrap method was used to create confidence intervals for the different points in time. The result showed that there were no points in time during which acceptable material was produced. One reason for this is the occurrence of a set of deviating values that were observed to have a sulphur content that exceeded 1,000 ppm. This report presents recommendations for various measures independently of any opinions SMA Mineral AB may have concerning the source of these values and whether they can possibly be avoided. / <p>Validerat; 20160612 (global_studentproject_submitter)</p>

The purpose of this dissertation was to empirically investigate the Type I error and power rates of four data transformations that produce a variety of non-normal distributions. Specifically, the transformations investigated were (a) the g-and-h, (b) the generalized lambda distribution (GLD), (c) the power method, and (d) the Burr families of distributions in the context of between-subjects and within-subjects analysis of variance (ANOVA). The traditional parametric F tests and their nonparametric counterparts, the Kruskal-Wallis (KW) and Friedman (FR) tests, were selected to be used in this investigation. The four data transformations produce non-normal distributions that have either valid or invalid probability density functions (PDFs). Specifically, the data generating procedures will produce distributions with valid PDFs if and only if the transformations are strictly increasing - otherwise the distributions are considered to be associated with invalid PDFs. As such, the primary objective of this study was to isolate and investigate the behaviors of the four data transformation procedures themselves while holding all other conditions constant (i.e., sample sizes, effect sizes, correlation levels, skew, kurtosis, random seed numbers, etc. all remain the same). The overall results of the Monte Carlo study generally suggest that when the distributions have valid probability density functions (PDFs) that the Type I error and power rates for the parametric (or nonparametric) tests were similar across all four data transformations. It is noted that there were some dissimilar results when the distributions were very skewed and near their associated boundary conditions for a valid PDF. These dissimilarities were most pronounced in the context of the KW and FR tests. In contrast, when the four transformations produced distributions with invalid PDFs, the Type I error and power rates were more frequently dissimilar for both the parametric F and nonparametric (KW, FR) tests. The dissimilarities were most pronounced when the distributions were skewed and heavy-tailed. For example, in the context of a parametric between subjects design, four groups of data were generated with (a) sample sizes of 10, (b) standardized effect size of 0.50 between groups, (c) skew of 2.5 and kurtosis of 60, (d) power method transformations generating distributions with invalid PDFs, and (e) g-and-h and GLD transformations both generating distributions with valid PDFs. The power results associated with the power method transformation showed that the F-test (KW test) was rejecting at a rate of .32 (.86). On the other hand, the power results associated with both the g-and-h and GLD transformations showed that the F-test (KW test) was rejecting at a rate of approximately .19 (.26). The primary recommendation of this study is that researchers conducting Monte Carlo studies in the context described herein should use data transformation procedures that produce valid PDFs. This recommendation is important to the extent that researchers using transformations that produce invalid PDFs increase the likelihood of limiting their study to the data generating procedure being used i.e. Type I error and power results may be substantially disparate between different procedures. Further, it also recommended that g-and-h, GLD, Burr, and fifth-order power method transformations be used if it is desired to generate distributions with extreme skew and/or heavy-tails whereas third-order polynomials should be avoided in this context.

Research has shown that goal orientation has a direct relationship with academic achievement for students. This relationship varies for South African students from different backgrounds. This mini dissertation investigated the relationship between academic achievement and goal orientation but moreover explored the mediating variables at play in this relationship. A quantitative correlational research study was employed with a sample size of 545 South African students ranging in age from 18 to 48 with a mean of 20.77 (SD = 2.94). Students completed an online survey, through Qualtrics. T tests yielded results suggesting that there was a significant difference (p = <.05) in the performance avoidance scores for historically advantaged students (M = 7.24, SD = 2.03) and historically disadvantaged students (M= 7.83, SD = 2.15), suggesting that historically disadvantaged students are more performance avoidant compared to historical advantaged students. Two way between groups ANOVA showed that the historical advantaged students (M = 65.39, SD= 14.30) scored higher academically compared to the historical disadvantaged students (M=54.42, SD=15.17). Structural equation modelling (SEM) produced results showing that Goal achievement (GAQ) related positively, with a large direct, significance effect with Culture (R^2=0.0, ᵝ = 0.71, C.R.= 4.91, p<.001), proposing that students who are individualistic (or traditional) perform better academically. / Mini Dissertation (MA)--University of Pretoria, 2016. / Psychology / MA / Unrestricted

This report investigates how prediction of stock markets with Artificial Neural Networks (ANN) is affected by altering aspects of data quantities. A short-term and a long-term perspective considering time delays are examined. Inspired by neurosciences, ANNs have shown great potential in terms of recognising patterns in nonlinear systems. Existing research suggests that ANN is an eminent model to predicting stock markets due to its dynamical characteristics. Closing prices of large-caps within the sectors of IT and Telecommunication represented by the Swedish of OMX30 Stockholm (OMXS30), have been leveraged as data. The ANNs are implemented as multilayer feedforward networks, trained using supervised learning. To identify specific configurations, the models have undergone extensive testing by mean squared errors and statistical analysis. The results obtained suggest that the short-term perspective is optimally predicted for significantly small numbers of time delays, and that optimal configurations do not alter for increasing quantities of data. No significant conclusions could be drawn from the results for the long-term perspective.Key words: ANOVA, Backpropagation, Configurations, Stock Prediction, Artficial Neural Networks