title: Experiences with a weighted decision tree learner

authors: Cleary, John G.

subjects: computer science

abstract: Machine learning algorithms for inferring decision trees typically choose a single “best” tree to describe the training data. Recent research has shown that classification performance can be significantly improved by voting predictions of multiple, independently produced decision trees. This paper describes an algorithm, OB1, that makes a weighted sum over many possible models. We describe one instance of OB1, that includes all possible decision trees as well as naïve Bayesian models. OB1 is compared with a number of other decision tree and instance based learning algorithms on some of the data sets from the UCI repository. Both an information gain and an accuracy measure are used for the comparison. On the information gain measure OB1 performs significantly better than all the other algorithms. On the accuracy measure it is significantly better than all the algorithms except naïve Bayes which performs comparably to OB1.

text: Experiences with a weighted decision tree learner Machine learning algorithms for inferring decision trees typically choose a single “best” tree to describe the training data. Recent research has shown that classification performance can be significantly improved by voting predictions of multiple, independently produced decision trees. This paper describes an algorithm, OB1, that makes a weighted sum over many possible models. We describe one instance of OB1, that includes all possible decision trees as well as naïve Bayesian models. OB1 is compared with a number of other decision tree and instance based learning algorithms on some of the data sets from the UCI repository. Both an information gain and an accuracy measure are used for the comparison. On the information gain measure OB1 performs significantly better than all the other algorithms. On the accuracy measure it is significantly better than all the algorithms except naïve Bayes which performs comparably to OB1.

year: 1998-05

title: Incorporating discontinuous preferences into the analysis of discrete choice experiments

authors: Campbell, Danny

subjects: discontinuous preferences

abstract: Data from a discrete choice experiment on improvements of rural landscape attributes are used to investigate the implications of discontinuous preferences on willingness to pay estimates. Using a multinomial error component logit model, we explore differences in scale and unexplained variance between respondents with discontinuous and continuous preferences and condition taste intensities on whether or not each attribute was considered by the respondent during the evaluation of alternatives. Results suggest that significant improvements in model performance can be achieved when discontinuous preferences are accommodated in the econometric specification, and that the magnitude and robustness of the willingness to pay estimates are sensitive to discontinuous preferences.

text: Incorporating discontinuous preferences into the analysis of discrete choice experiments Data from a discrete choice experiment on improvements of rural landscape attributes are used to investigate the implications of discontinuous preferences on willingness to pay estimates. Using a multinomial error component logit model, we explore differences in scale and unexplained variance between respondents with discontinuous and continuous preferences and condition taste intensities on whether or not each attribute was considered by the respondent during the evaluation of alternatives. Results suggest that significant improvements in model performance can be achieved when discontinuous preferences are accommodated in the econometric specification, and that the magnitude and robustness of the willingness to pay estimates are sensitive to discontinuous preferences.

year: 2007-09

title: Is there a lack of science resources and specialists for kaiako at Kura reo o Waikato?

authors: Hopkins, Aareka

subjects: Kura kaupapa

abstract: The New Zealand debates on culture and science education for Maaori are grounded in the concern for the under-achievement of tauira in science. In 1995, a lack of subject experts, specialists and resources to implement the Ministry of Education’s science curriculum was identified. I investigated the concept of a mobile science laboratory to provide subject experts, specialists and resources to Kura Reo o Tainui as a way of improving and enhancing tauira literacy and engagement in puutaiao. This study used a semi-structured survey to elicit the whakaaro and perceptions of kaiako puutaiao from four Wharekura, three Kura Kaupapa Maaori, and three Rumaki Total Immersion classes in Waikato-Tainui, using registered participants in the inaugural Kura Reo o Tainui Waananga in 2008 to select survey participants.

text: Is there a lack of science resources and specialists for kaiako at Kura reo o Waikato? The New Zealand debates on culture and science education for Maaori are grounded in the concern for the under-achievement of tauira in science. In 1995, a lack of subject experts, specialists and resources to implement the Ministry of Education’s science curriculum was identified. I investigated the concept of a mobile science laboratory to provide subject experts, specialists and resources to Kura Reo o Tainui as a way of improving and enhancing tauira literacy and engagement in puutaiao. This study used a semi-structured survey to elicit the whakaaro and perceptions of kaiako puutaiao from four Wharekura, three Kura Kaupapa Maaori, and three Rumaki Total Immersion classes in Waikato-Tainui, using registered participants in the inaugural Kura Reo o Tainui Waananga in 2008 to select survey participants.

year: 2010-08