This study assesses the effectiveness of stratification, based on photo-interpreted forest types, for strategic inventory. It uses results (from stratified sampling) for Total Merchantable Volume (TMV) in 18 Inventory Areas in Tasmanian State forest. The variance of the TMV as determined from stratified sampling is compared with the estimated variance of a simple random sample using the same nu...

We study parameter inference in large-scale latent variable models. We first propose an unified treatment of online inference for latent variable models from a non-canonical exponential family, and draw explicit links between several previously proposed frequentist or Bayesian methods. We then propose a novel inference method for the frequentist estimation of parameters, that adapts MCMC method...

The use of the least squares method to calculate the best-fitting line through a two-dimensional scatter plot typically requires the user to assume that one of the variables depends on the other. However, in many cases the relationship between the two variables is more complex, and it is not valid to say that one variable is independent and the other is dependent. When analysing such data resea...

NMR spectral data from control subject and mice with (A) S. aureus infection and (B) S. aureus and S. pneumoniae infection and showing the separation between samples along the type of infection. Two components encapsulate 97 % (A) and 83 % (B) of the interclass variation. Fig. 2: The variable importance plot (VIP) shows the relative contribution that each metabolite makes to the difference betw...

The reduction of 1,1-diaryl-2,2-dicyanoethylenes with SmI(2) in THF was studied in the presence of four proton donors: H(2)O, MeOH, i-PrOH and trifluoroethanol (TFE). The kinetic order for the first two is nearly unity at low proton donor concentrations and approaches four at high concentrations, whereas, for i-PrOH and TFE, the log-log plot is linear with a slope smaller than one. Detailed ana...

Aggregation of hyperphosphorylated tau is a major hallmark of many neurodegenerative diseases, including Alzheimer disease (AD). In vivo imaging with PET may offer important insights into pathophysiologic mechanisms, diagnosis, and disease progression. We describe different strategies for quantification of 18F-AV-1451 (T807) tau binding, including models with blood sampling and noninvasive alte...

This Master’s thesis is mostly focused on Bayesian methods for the selection and testing of discrete mixture models. The main problem that is studied in the project is the analysis of data sets of several categorical variables (e.g. test items, symptoms, genes) collected on a set of subjects. We fit a discrete mixture model to the data which means that the dependencies among the different varia...

1. There is currently much interest in replacing the design-based component of conventional distance sampling methods by a modelling approach where animal densities are related to environmental covariates. These models allow identification of relationships between density and covariates. One of the uses of such models is to assess the effects of some intervention on numbers for species of conse...

The relationship between variables is vital in data analysis. The scatter plot, for instance, gives an easy preliminary exploratory analysis for finding relationship between two variables, if any. Statistical method such as correlation and linear relationship are standard tools in most statistical packages. For circular variables that take value on the circumference of a circle, the analysis ho...