Most psychological studies rely on student samples. Students are usually considered as more homogenous than representative samples both within and across countries. However, little is known about the nature of the differences between student and representative samples. This is an important gap, also because knowledge about the degree of difference between student and representative samples may ...

This contribution determines suitable fingerprinting properties for sediment source discrimination within theAmrovan and Atary catchments in Semnan Province, Iran. These catchments are representative of a range of geology formations and should therefore provide a meaningful basis for a general assessment of the degree of sediment source discrimination afforded by a range of fingerprint properti...

The lateral sealing ability of a normal fault is a major factor in creating hydrocarbon traps. Therefore, a methodology for assessing the sealing ability of faults in the siliciclastic sequences of subsidence basins has been established; moreover, by using this methodology, the uncertainty inherent in hydrocarbon exploration can be decreased. Moreover, the petrophysical properties of fault roc...

A new approach, termed whole-community RNA amplification (WCRA), was developed to provide sufficient amounts of mRNAs from environmental samples for microarray analysis. This method employs fusion primers (six to nine random nucleotides with an attached T7 promoter) for the first-strand synthesis. The shortest primer (T7N6S) gave the best results in terms of the yield and representativeness of ...

In his famous book " Democracy and its Critics " (1989), Robert A. Dahl argues that, historically speaking, there have been two transformations of democracy. These transformations have brought about different models of democratic governance and different interpretations of the concept of democracy. By the fi rst transformation Dahl refers to the the emergence of the classical model of democracy...

Although a large number of new image classification algorithms have been developed, they are rarely tested with the same classification task. In this research, with the same Landsat Thematic Mapper (TM) data set and the same classification scheme over Guangzhou City, China, we tested two unsupervised and 13 supervised classification algorithms, including a number of machine learning algorithms ...

Surveys of people's opinions are fraught with difficulties. It is easier to obtain information from those who respond to text messages or to emails than to attempt to obtain a representative sample. Samples of the population that are selected non-randomly in this way are termed convenience samples as they are easy to recruit. This introduces a sampling bias. Such non-probability samples have me...

This paper reviews the four types of validity that make up Cook and Campbell's traditional approach for social science research in general and psychological research in particular: internal validity, statistical conclusion validity, external validity, and construct validity. The most important generalizability threat to the validity of jury research is not likely a selection main effect (i.e., ...

In order to reduce human efforts, there has been increasing interest in applying active learning for training text classifiers. This paper describes a straightforward active learning heuristic, representative sampling, which explores the clustering structure of ‘uncertain’ documents and identifies the representative samples to query the user opinions, for the purpose of speeding up the converge...