title: SMOTE for regression

authors: Torgo, Luís

subjects: computer science

abstract: Several real world prediction problems involve forecasting rare values of a target variable. When this variable is nominal we have a problem of class imbalance that was already studied thoroughly within machine learning. For regression tasks, where the target variable is continuous, few works exist addressing this type of problem. Still, important application areas involve forecasting rare extreme values of a continuous target variable. This paper describes a contribution to this type of tasks. Namely, we propose to address such tasks by sampling approaches. These approaches change the distribution of the given training data set to decrease the problem of imbalance between the rare target cases and the most frequent ones. We present a modification of the well-known Smote algorithm that allows its use on these regression tasks. In an extensive set of experiments we provide empirical evidence for the superiority of our proposals for these particular regression tasks. The proposed SmoteR method can be used with any existing regression algorithm turning it into a general tool for addressing problems of forecasting rare extreme values of a continuous target variable.

text: SMOTE for regression Several real world prediction problems involve forecasting rare values of a target variable. When this variable is nominal we have a problem of class imbalance that was already studied thoroughly within machine learning. For regression tasks, where the target variable is continuous, few works exist addressing this type of problem. Still, important application areas involve forecasting rare extreme values of a continuous target variable. This paper describes a contribution to this type of tasks. Namely, we propose to address such tasks by sampling approaches. These approaches change the distribution of the given training data set to decrease the problem of imbalance between the rare target cases and the most frequent ones. We present a modification of the well-known Smote algorithm that allows its use on these regression tasks. In an extensive set of experiments we provide empirical evidence for the superiority of our proposals for these particular regression tasks. The proposed SmoteR method can be used with any existing regression algorithm turning it into a general tool for addressing problems of forecasting rare extreme values of a continuous target variable.

year: 2013

title: Towards rapid assay of cryptotephra in peat cores: review and evaluation of selected methods

authors: Gehrels, Maria J.

subjects: tephra

abstract: Peat bogs are highly effective archives for the preservation and detection of cryptotephra but the conventional methods used to detect these hidden, diminutive layers are destructive and can be time consuming. We briefly review methods that have been used for cryptotephra detection and evaluate the potential of a range of alternative reconnaissance methods, both non-destructive and destructive, to provide for more rapid examination of continuous cryptotephra content in peat cores. The techniques evaluated—magnetic susceptibility (MS), spectrophotometry, and X-ray fluorescence—are used to pick out compositional contrasts between tephra deposits and peat. Measurements of organic content are also evaluated as a potential guide to tephra content based on an inverse relationship. Although we find limitations to each method, particularly where deployed at the distal-most end of tephra dispersal, there is potential for all methods to be used in the detection of cryptotephra where time or material is limited. These methods can also provide additional sedimentological and stratigraphic information for studies of peat cores. However, where a reliable cryptotephra profile is required, we conclude that there is no quick or easy substitute for the conventional extraction-microscopy method.

text: Towards rapid assay of cryptotephra in peat cores: review and evaluation of selected methods Peat bogs are highly effective archives for the preservation and detection of cryptotephra but the conventional methods used to detect these hidden, diminutive layers are destructive and can be time consuming. We briefly review methods that have been used for cryptotephra detection and evaluate the potential of a range of alternative reconnaissance methods, both non-destructive and destructive, to provide for more rapid examination of continuous cryptotephra content in peat cores. The techniques evaluated—magnetic susceptibility (MS), spectrophotometry, and X-ray fluorescence—are used to pick out compositional contrasts between tephra deposits and peat. Measurements of organic content are also evaluated as a potential guide to tephra content based on an inverse relationship. Although we find limitations to each method, particularly where deployed at the distal-most end of tephra dispersal, there is potential for all methods to be used in the detection of cryptotephra where time or material is limited. These methods can also provide additional sedimentological and stratigraphic information for studies of peat cores. However, where a reliable cryptotephra profile is required, we conclude that there is no quick or easy substitute for the conventional extraction-microscopy method.

year: 2008-02

title: Cultural Conversations in a Counselling Context

authors: Harkness, Jane

subjects: counselling

abstract: This research project focuses on counselling practice with Māori women who have engaged in counselling in relation to overcoming the effects of both historic and recent sexual abuse. The researcher / counsellor is pakeha. The counsellor / researcher, researches her practice and its possible effects through research interviews with three women. The project offers a reflection on her practice ethics and on what she learns from the women. In particular, she explores the intentions and effects of an orientation to counselling that includes offering and taking up conversations about aspects of cultural identity. She explores the effect of the counselling conversations where aspects of ethno-cultural identity have been included on the women‟s sense of identity. She explores what she draws on as a Pakeha counsellor when offering and taking up conversations about aspects of cultural identity. She also explores the effects of offering and taking up conversations about aspects of cultural identity for the work of counselling. The project shows the researcher‟s responses to the research meetings and the learning she takes to her ongoing counselling practice.

text: Cultural Conversations in a Counselling Context This research project focuses on counselling practice with Māori women who have engaged in counselling in relation to overcoming the effects of both historic and recent sexual abuse. The researcher / counsellor is pakeha. The counsellor / researcher, researches her practice and its possible effects through research interviews with three women. The project offers a reflection on her practice ethics and on what she learns from the women. In particular, she explores the intentions and effects of an orientation to counselling that includes offering and taking up conversations about aspects of cultural identity. She explores the effect of the counselling conversations where aspects of ethno-cultural identity have been included on the women‟s sense of identity. She explores what she draws on as a Pakeha counsellor when offering and taking up conversations about aspects of cultural identity. She also explores the effects of offering and taking up conversations about aspects of cultural identity for the work of counselling. The project shows the researcher‟s responses to the research meetings and the learning she takes to her ongoing counselling practice.

year: 2008