title: Gradient boosted trees for evolving data streams

authors: Gunasekara, Nuwan Amila

subjects: computer science

abstract: Gradient Boosting is a widely-used machine learning technique that has proven highly effective in batch learning. However, its effectiveness in stream learning contexts lags behind bagging-based ensemble methods, which currently dominate the field. One reason for this discrepancy is the challenge of adapting the booster to new concept following a concept drift. Resetting the entire booster can lead to significant performance degradation as it struggles to learn the new concept. Resetting only some parts of the booster can be more effective, but identifying which parts to reset is difficult, given that each boosting step builds on the previous prediction. To overcome these difficulties, we propose Streaming Gradient Boosted Trees (Sgbt), which is trained using weighted squared loss elicited in XGBoost. Sgbt exploits trees with a replacement strategy to detect and recover from drifts, thus enabling the ensemble to adapt without sacrificing the predictive performance. Our empirical evaluation of Sgbt on a range of streaming datasets with challenging drift scenarios demonstrates that it outperforms current state-of-the-art methods for evolving data streams.

text: Gradient boosted trees for evolving data streams Gradient Boosting is a widely-used machine learning technique that has proven highly effective in batch learning. However, its effectiveness in stream learning contexts lags behind bagging-based ensemble methods, which currently dominate the field. One reason for this discrepancy is the challenge of adapting the booster to new concept following a concept drift. Resetting the entire booster can lead to significant performance degradation as it struggles to learn the new concept. Resetting only some parts of the booster can be more effective, but identifying which parts to reset is difficult, given that each boosting step builds on the previous prediction. To overcome these difficulties, we propose Streaming Gradient Boosted Trees (Sgbt), which is trained using weighted squared loss elicited in XGBoost. Sgbt exploits trees with a replacement strategy to detect and recover from drifts, thus enabling the ensemble to adapt without sacrificing the predictive performance. Our empirical evaluation of Sgbt on a range of streaming datasets with challenging drift scenarios demonstrates that it outperforms current state-of-the-art methods for evolving data streams.

year: 2024

title: Grappling with the complexity of the New Zealand Curriculum: Next steps in exploring the NZC in initial teacher education.

authors: Bailey, Judy

subjects: teacher education

abstract: Teacher educators in New Zealand are charged with supporting student teachers' understandings of the New Zealand Curriculum document (Ministry of Education, 2007). Integral to this challenge is the need to provide relevant knowledge and understandings that are contextually and pedagogically appropriate (Fullan, 2007; Jasman, 2003). Aspects of the "front end" of the New Zealand Curriculum document such as the vision, principles, values and key competencies along with the learning area statements need to be understood by newly graduated teachers who will be applying this curriculum in their own classrooms. This paper reports on ongoing research investigating and reflecting on student-teacher understandings of these components of the New Zealand curriculum, on completion of three different compulsory papers within the Bachelor of Teaching degree and Graduate Diploma of Teaching (Primary). Implications for pre-service teacher education and for supporters of provisionally registered teachers are considered.

text: Grappling with the complexity of the New Zealand Curriculum: Next steps in exploring the NZC in initial teacher education. Teacher educators in New Zealand are charged with supporting student teachers' understandings of the New Zealand Curriculum document (Ministry of Education, 2007). Integral to this challenge is the need to provide relevant knowledge and understandings that are contextually and pedagogically appropriate (Fullan, 2007; Jasman, 2003). Aspects of the "front end" of the New Zealand Curriculum document such as the vision, principles, values and key competencies along with the learning area statements need to be understood by newly graduated teachers who will be applying this curriculum in their own classrooms. This paper reports on ongoing research investigating and reflecting on student-teacher understandings of these components of the New Zealand curriculum, on completion of three different compulsory papers within the Bachelor of Teaching degree and Graduate Diploma of Teaching (Primary). Implications for pre-service teacher education and for supporters of provisionally registered teachers are considered.

year: 2011

title: He tirohanga ki ngā iwi o Hauraki

authors: Ngāpō, Korohere

subjects: Kōrero nehe

abstract: Ahakoa kua kīia nei tekau mā rua ngā iwi o Hauraki i ēnei rangi, kua mōhiotia whānuitia e ngā tūnohunohu me ngā tohunga whakapapa o te kāinga e toru ngā tino nohonga tūturu ake o ngā iwi o Hauraki i mua i te tae putuputu mai o te iwi Pākehā. Ka mutu, he whakarāpopoto noa iho tēnei tuhinga ki ngā tūrangawaewae me ngā tapuwae o ngā iwi ki roto i ngā whaitua o Te Tara o Te Ika-a-Māui-tikitiki-a-Taranga. Ehara i te mea kua ruku hōhonu ake ahau ki ngā āhuatanga katoa o ngā whakapapa o Hauraki engari he paku makamaka tirotiro noa iho nā te rarahi, nā te whānui rawa o tēnei kaupapa. Mehemea ka tōminamina te tangata kia mōhio ai ki ngā hītori o Hauraki mokori anō tana whana atu ki ngā wāhi tapu, ki ngā kōrero tuku iho a ngā mātanga whakapapa.

Mehemea e tōminamina ana te tangata kia mōhio ai ko wai mā ngā tūpuna o Hauraki i ngā wā o mua, me hoki whakamuri ki ngā iwi tuatahi tae noa mai ki ngā iwi 12 e noho atu ana ki ngā ripa tauārai o Hauraki ā mohoa nei.

text: He tirohanga ki ngā iwi o Hauraki Ahakoa kua kīia nei tekau mā rua ngā iwi o Hauraki i ēnei rangi, kua mōhiotia whānuitia e ngā tūnohunohu me ngā tohunga whakapapa o te kāinga e toru ngā tino nohonga tūturu ake o ngā iwi o Hauraki i mua i te tae putuputu mai o te iwi Pākehā. Ka mutu, he whakarāpopoto noa iho tēnei tuhinga ki ngā tūrangawaewae me ngā tapuwae o ngā iwi ki roto i ngā whaitua o Te Tara o Te Ika-a-Māui-tikitiki-a-Taranga. Ehara i te mea kua ruku hōhonu ake ahau ki ngā āhuatanga katoa o ngā whakapapa o Hauraki engari he paku makamaka tirotiro noa iho nā te rarahi, nā te whānui rawa o tēnei kaupapa. Mehemea ka tōminamina te tangata kia mōhio ai ki ngā hītori o Hauraki mokori anō tana whana atu ki ngā wāhi tapu, ki ngā kōrero tuku iho a ngā mātanga whakapapa.

Mehemea e tōminamina ana te tangata kia mōhio ai ko wai mā ngā tūpuna o Hauraki i ngā wā o mua, me hoki whakamuri ki ngā iwi tuatahi tae noa mai ki ngā iwi 12 e noho atu ana ki ngā ripa tauārai o Hauraki ā mohoa nei.

year: 2016