A Predictive Model for Assessment of Successful Outcome in Posterior Spinal Fusion Surgery

Background: Low back pain is a common problem in many people. Neurosurgeons recommend posterior spinal fusion (PSF) surgery as one of the therapeutic strategies to the patients with low back pain. Due to the high risk of this type of surgery and the critical importance of making the right decision, accurate prediction of the surgical outcome is one of the main concerns for the neurosurgeons.Methods: In this study, 12 types of multi-layer perceptron (MLP) networks and 66 radial basis function (RBF) networks as the types of artificial neural network methods and a logistic regression (LR) model created and compared to predict the satisfaction with PSF surgery as one of the most well-known spinal surgeries.Results: The most important clinical and radiologic features as twenty-seven factors for 480 patients (150 males, 330 females; mean age 52.32 ± 8.39 years) were considered as the model inputs that included: age, sex, type of disorder, duration of symptoms, job, walking distance without pain (WDP), walking distance without sensory (WDS) disorders, visual analog scale (VAS) scores, Japanese Orthopaedic Association (JOA) score, diabetes, smoking, knee pain (KP), pelvic pain (PP), osteoporosis, spinal deformity and etc. The indexes such as receiver operating characteristic–area under curve (ROC-AUC), positive predictive value, negative predictive value and accuracy calculated to determine the best model. Postsurgical satisfaction was 77.5% at 6 months follow-up. The patients divided into the training, testing, and validation data sets.Conclusion: The findings showed that the MLP model performed better in comparison with RBF and LR models for prediction of PSF surgery.Keywords: Posterior spinal fusion surgery (PSF); Prediction, Surgical satisfaction; Multi-layer perceptron (MLP); Logistic regression (LR) (PDF) A Predictive Model for Assessment of Successful Outcome in Posterior Spinal Fusion Surgery. Available from: https://www.researchgate.net/publication/325679954_A_Predictive_Model_for_Assessment_of_Successful_Outcome_in_Posterior_Spinal_Fusion_Surgery [accessed Jul 11 2019].Peer reviewe

Cervical cancer risk prediction with robust ensemble and explainable black boxes method

Clinical decision support systems (CDSS) that make use of algorithms based on intelligent systems, such as machine learning or deep learning, they sufer from the fact that often the methods used are hard to interpret and difcult to understand on how some decisions are made; the opacity ofsome methods, sometimes voluntary due to problems such as data privacy or the techniques used to protect intellectual property, makes these systems very complicated. Besides this series of problems, the results obtained also sufer from the poor possibility of being interpreted; in the clinical context therefore it is required that the methods used are as accurate as possible, transparent techniques and explainable results. In this work the problem of the development of cervical cancer is treated, a disease that mainly afects the female population. In order to introduce advanced machine learning techniques in a clinical decision support system that can be transparent and explainable, a robust, accurate ensemble method is presented, in terms of error and sensitivity linked to the classifcation of possible development of the aforementioned pathology and advanced techniques are also presented of explainability and interpretability (Explanaible Machine Learning) applied to the context of CDSS such as Lime and Shapley. The results obtained, as well as being interesting, are understandable and can be implemented in the treatment of this type of problem

Comparative analysis of machine learning algorithms used in the diagnosis of Cervical cancers

Serviks (Rahim Ağzı Kanseri) ölüme yol açan ve ölüm oranı en yüksek kanser türlerinden biri olarak görülmektedir. Serviks kanseri kadın kanseri arasında meme kanserinden sonra 2. Sırada yer almaktadır. Günümüzde makine öğrenmesi yöntemlerinin kullanımıyla biyomedikal veri kümelerinin analizi yaygınlaşmıştır. Özellikle kanser gibi habis hastalıkların erken teşhisinde tahminleme sistemleri önemli rol oynamaktadır. Serviks kanseri üzerinde belirlenmiş risk faktörlerine yönelik yapılan tahminler tutarlı olabilmektedir. Bu çalışmada serviks kanserinin teşhisinde kullanılan makine öğrenmesi metotlarının başarıları karşılaştırılmıştır. Çalışmada kullanılan 23 ayrı makine öğrenmesi algoritması, 838 örnek, 32 öznitelik ve 4 hedef değişkenli veri seti üzerinde test edilmiştir. Veri önişleme, özellik seçimi ve sınıflandırma olmak üzere üç aşamadan oluşan analizde sınıflandırma performansları; sınıflandırma doğruluğu, kesinlik, duyarlılık ve F-ölçütü metrikleri kullanılarak analiz edilmiştir. Analiz sonucunda RepTree algoritmasının en başarılı sonuç veren model olduğu belirlenmiştir.Cervix (Cervical Cancer) is seen as one of the cancer types that causes death and has the highest mortality rate. Cervical cancer is the second most common female cancer after breast cancer. Today, the analysis of biomedical datasets has become widespread with the use of machine learning methods. Prediction systems play an important role in the early diagnosis of malignant diseases such as cancer. Estimates of risk factors for cervical cancer can be consistent. In this study, the success of machine learning methods used in the diagnosis of cervical cancers was compared. 23 different machine learning algorithms used in the study were tested on a data set with 838 samples, 32 features and 4 target variables. Classification performances in the analysis consisting of three stages: data preprocessing, feature selection and classification; Comparisons were made using classification accuracy, precision, sensitivity, and F-criterion metrics. As a result of the analysis, it was determined that the RepTree algorithm was the model that gave the most successful results

Conceptual model of the factors impacting the adoption of Neuromarketing Technologies

The traditional methods are fading away with scientific methods of taking a plunge into the field of market research. Neuromarketing is the recent technique in market research that is attracting a lot of interest. Despite this boom, large enterprises seem to resist implementing them in their marketing activities, thus limiting the development of the discipline. This research reflects on the main factors that impact the adoption of neuromarketing within large-scale enterprises from a bibliographical perspective. The importance of acceptance of neuromarketing lies upon the fact that business professional, academicians and consumers’ attitudes are mixed and in a state of uncertainty. Neuromarketing is waiting for a strong academic and experimental platform on which, it can stand firmly. Therefore, it becomes extremely important to understand the barriers and specifically the enablers of adopting Neuromarketing techniques. This paper synthesizes the literature review related to theoretical models and factors of adoption and organizational success of technological innovations and exposes a conceptual model of factors impacting the adoption of Neuromarketing. The model is based on four types of factors: Individuals factors, technological factors, organizational factors and environmental factors, the interrelationships of these factors have been established using the TOE model and a literature review. This research is motivated by the willingness to fill the knowledge gap on the factors impacting the adoption of Neuromarketing, and contributes to the enrichment of the literature on the subject by proposing a conceptual model that will be the guideline and pilot of a future empirical study.     JEL Classification: M31 Paper type: Theoretical Research The traditional methods are fading away with scientific methods of taking a plunge into the field of market research. Neuromarketing is the recent technique in market research that is attracting a lot of interest. Despite this boom, large enterprises seem to resist implementing them in their marketing activities, thus limiting the development of the discipline. This research reflects on the main factors that impact the adoption of neuromarketing within large-scale enterprises from a bibliographical perspective. The importance of acceptance of neuromarketing lies upon the fact that business professional, academicians and consumers’ attitudes are mixed and in a state of uncertainty. Neuromarketing is waiting for a strong academic and experimental platform on which, it can stand firmly. Therefore, it becomes extremely important to understand the barriers and specifically the enablers of adopting Neuromarketing techniques. This paper synthesizes the literature review related to theoretical models and factors of adoption and organizational success of technological innovations and exposes a conceptual model of factors impacting the adoption of Neuromarketing. The model is based on four types of factors: Individuals factors, technological factors, organizational factors and environmental factors, the interrelationships of these factors have been established using the TOE model and a literature review. This research is motivated by the willingness to fill the knowledge gap on the factors impacting the adoption of Neuromarketing, and contributes to the enrichment of the literature on the subject by proposing a conceptual model that will be the guideline and pilot of a future empirical study.     JEL Classification: M31 Paper type: Theoretical Research&nbsp

Machine Learning na previsão de Cancro Colorretal em função de alterações metabólicas

No mundo atual, a quantidade de informação disponível nos mais variados setores é cada vez maior. É o caso da área da saúde, onde a recolha e tratamento de dados biomédicos procuram melhorar a tomada de decisão no tratamento a aplicar a um doente, recorrendo a ferramentas baseadas em Machine Learning. Machine Learning é uma área da Inteligência Artificial em que através da aplicação de algoritmos a um conjunto de dados é possível prever resultados ou até descobrir relações entre estes que seriam impercetíveis à primeira vista. Com este projeto pretende-se realizar um estudo em que o objetivo é investigar diversos algoritmos e técnicas de Machine Learning, de modo a identificar se o perfil de acilcarnitinas pode constituir um novo marcador bioquímico para a predição e prognóstico do Cancro Colorretal. No decurso do trabalho, foram testados diferentes algoritmos e técnicas de pré-processamento de dados. Foram realizadas três experiências distintas com o objetivo de validar as previsões dos modelos construídos para diferentes cenários, nomeadamente: prever se o paciente tem Cancro Colorretal, prever qual a doença que o paciente tem (Cancro Colorretal e outras doenças metabólicas) e prever se este tem ou não alguma doença. Numa primeira análise, os modelos desenvolvidos apresentam bons resultados na triagem de Cancro Colorretal. Os melhores resultados foram obtidos pelos algoritmos Random Forest e Gradient Boosting, em conjunto com técnicas de balanceamento dos dados e Feature Selection, nomeadamente Random Oversampling, Synthetic Oversampling e Recursive Feature SelectionIn today´s world, the amount of information available in various sectors is increasing. That is the case in the healthcare area, where the collection and treatment of biochemical data seek to improve the decision-making in the treatment to be applied to a patient, using Machine Learning-based tools. Machine learning is an area of Artificial Intelligence in which applying algorithms to a dataset makes it possible to predict results or even discover relationships that would be unnoticeable at first glance. This project’s main objective is to study several algorithms and techniques of Machine Learning to identify if the acylcarnitine profile may constitute a new biochemical marker for the prediction and prognosis of rectal cancer. In the course of the work, different algorithms and data preprocessing techniques were tested. Three different experiments were carried out to validate the predictions of the models built for different scenarios, namely: predicting whether the patient has Colorectal Cancer, predicting which disease the patient has (Colorectal Cancer and other metabolic diseases) and predicting whether he has any disease. As a first analysis, the developed models showed good results in Colorectal Cancer screening. The best results were obtained by the Random Forest and Gradient Boosting algorithms, together with data balancing and feature selection techniques, namely Random Oversampling, Synthetic Oversampling and Recursive Feature Selectio

From the Occam's Razor to a simple, efficient and robust text categorization approach

Orientadores: Akebo Yamakami, Tiago Agostinho de AlmeidaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de ComputaçãoResumo: Categorização de textos é um problema que tem recebido muita atenção nos últimos anos devido ao aumento expressivo no volume de informações textuais. O processo manual de categorizar documentos de texto é cansativo, tedioso, demorado e muitas vezes impraticável quando o volume de dados é muito grande. Portanto, existe uma grande demanda para que esse processo seja realizado de maneira automática através de métodos computacionais. Embora vários métodos já tenham sido propostos, muitos sofrem com o problema da maldição da dimensionalidade ou apresentam alto custo computacional, inviabilizando seu uso em cenários reais. Diante disso, esta tese apresenta um método de categorização de texto baseado no princípio da descrição mais simples, nomeado MDLText, que é eficiente, rápido, escalável e multiclasse. Ele possui aprendizado rápido, incremental e é suficientemente robusto para evitar o problema de superajustamento aos dados, o que é altamente desejável em problemas reais, dinâmicos, online e de grande porte. Experimentos realizados com bases de dados reais, grandes e públicas, seguidos por uma análise estatística dos resultados, indicam que o MDLText oferece um excelente balanceamento entre poder preditivo e custo computacional. Diante desses bons resultados, foi proposta uma generalização inicial do método para lidar também com problemas não-textuais, o que resultou em um método de classificação, nomeado MDLClass, que é simples, rápido e pode ser aplicado em problemas binários e multiclasses. A análise estatística dos resultados indicou que ele é equivalente à maioria dos métodos considerados o estado-da-arte em classificaçãoAbstract: ext categorization has received attention in recent years because of the ever-increasing volume of text information. For large number of documents, a manual classification is tiresome, tedious, time-consuming, and impractical, making computational methods attractive to deal with this task. The available methods that address this problem suffer from their computational burden and the curse of dimensionality, undermining their applicability in real scenarios. To overcome this limitation, we propose a simpler, faster, scalable and more efficient classification method based on the minimum description length principle, named MDLText. Its incremental and faster learning process makes it suitable to cope with data overfitting, which is desirable for real and large-scale problems. Experiments performed on real, public, and large-scale datasets followed by statistical analyses indicate that the MDLText provides an excellent trade-off between predictive capability and computational cost. Motivated by these results, we propose a generalized method, named MDLClass, to encompass non-textual problems. Similar to MDLText, this extension is simple and fast, and can also be applied to binary and multiclass classification problems. Statistical analyses show that MDLClass is equivalent to most of the state-of-the-art classification methodsDoutoradoAutomaçãoDoutor em Engenharia Elétrica141089/2013-0CNP