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Preoperative Prognosis Assessment of Lumbar Spinal Surgery for Low Back Pain and Sciatica Patients based on Multimodalities and Multimodal Learning

arXiv.org Artificial Intelligence

Low back pain (LBP) and sciatica may require surgical therapy when they are symptomatic of severe pain. However, there is no effective measures to evaluate the surgical outcomes in advance. This work combined elements of Eastern medicine and machine learning, and developed a preoperative assessment tool to predict the prognosis of lumbar spinal surgery in LBP and sciatica patients. Standard operative assessments, traditional Chinese medicine body constitution assessments, planned surgical approach, and vowel pronunciation recordings were collected and stored in different modalities. Our work provides insights into leveraging modality combinations, multimodals, and fusion strategies. The interpretability of models and correlations between modalities were also inspected. Based on the recruited 105 patients, we found that combining standard operative assessments, body constitution assessments, and planned surgical approach achieved the best performance in 0.81 accuracy. Our approach is effective and can be widely applied in general practice due to simplicity and effective.


All About Decision Tree from Scratch with Python Implementation

#artificialintelligence

Formally a decision tree is a graphical representation of all possible solutions to a decision. These days, tree-based algorithms are the most commonly used algorithms in case of supervised learning scenarios. They are easier to interpret and visualize with great adaptability. We can use tree-based algorithms for both regression and classification problems, However, most of the time they are used for classification problem. Let's understand a decision tree from an example: Yesterday evening, I skipped dinner at my usual time because I was busy taking care of some stuff. Later in the night, I felt butterflies in my stomach.


How To Implement ML Models With Small Datasets

#artificialintelligence

Machine learning is now being implemented in several different applications today. People these days are figuring out how they can use the power of machine learning in their domain. But they often come across the problem of lack of data. The data is not sufficient to build a predictive model over it. Also, when we build predictive models over this amount of data, often the model is overfitted and does not perform well.


Four Key Announcements from H2O World San Francisco

#artificialintelligence

Last week at H2O World San Francisco, H2O.ai announced a number of improvements to Driverless AI, H2O, Sparkling Water, and AutoML, as well as several new partnerships for Driverless AI. The improvements provide incremental improvements across the platform, while the partnerships reflect H2O.ai expanding their audience and capabilities. This piece is intended to provide guidance to data analysts, data scientists, and analytic professionals working on including machine learning in their workflows. H2O.ai has integrated H2O Driverless AI with Alteryx Designer; the connector is available for download in the Alteryx Analytics Gallery. This will permit Alteryx users to implement more advanced and automatic machine learning algorithms into analytic workflows in Designer, as well as doing automatic feature engineering for their machine learning models.


Differentially Private Contextual Linear Bandits

Neural Information Processing Systems

We study the contextual linear bandit problem, a version of the standard stochastic multi-armed bandit (MAB) problem where a learner sequentially selects actions to maximize a reward which depends also on a user provided per-round context. Though the context is chosen arbitrarily or adversarially, the reward is assumed to be a stochastic function of a feature vector that encodes the context and selected action. Our goal is to devise private learners for the contextual linear bandit problem. We first show that using the standard definition of differential privacy results in linear regret. So instead, we adopt the notion of joint differential privacy, where we assume that the action chosen on day t is only revealed to user t and thus needn't be kept private that day, only on following days. We give a general scheme converting the classic linear-UCB algorithm into a joint differentially private algorithm using the tree-based algorithm. We then apply either Gaussian noise or Wishart noise to achieve joint-differentially private algorithms and bound the resulting algorithms' regrets. In addition, we give the first lower bound on the additional regret any private algorithms for the MAB problem must incur.


Differentially Private Contextual Linear Bandits

Neural Information Processing Systems

We study the contextual linear bandit problem, a version of the standard stochastic multi-armed bandit (MAB) problem where a learner sequentially selects actions to maximize a reward which depends also on a user provided per-round context. Though the context is chosen arbitrarily or adversarially, the reward is assumed to be a stochastic function of a feature vector that encodes the context and selected action. Our goal is to devise private learners for the contextual linear bandit problem. We first show that using the standard definition of differential privacy results in linear regret. So instead, we adopt the notion of joint differential privacy, where we assume that the action chosen on day t is only revealed to user t and thus needn't be kept private that day, only on following days. We give a general scheme converting the classic linear-UCB algorithm into a joint differentially private algorithm using the tree-based algorithm. We then apply either Gaussian noise or Wishart noise to achieve joint-differentially private algorithms and bound the resulting algorithms' regrets. In addition, we give the first lower bound on the additional regret any private algorithms for the MAB problem must incur.


Differentially Private Contextual Linear Bandits

arXiv.org Machine Learning

We study the contextual linear bandit problem, a version of the standard stochastic multi-armed bandit (MAB) problem where a learner sequentially selects actions to maximize a reward which depends also on a user provided per-round context. Though the context is chosen arbitrarily or adversarially, the reward is assumed to be a stochastic function of a feature vector that encodes the context and selected action. Our goal is to devise private learners for the contextual linear bandit problem. We first show that using the standard definition of differential privacy results in linear regret. So instead, we adopt the notion of joint differential privacy, where we assume that the action chosen on day $t$ is only revealed to user $t$ and thus needn't be kept private that day, only on following days. We give a general scheme converting the classic linear-UCB algorithm into a joint differentially private algorithm using the tree-based algorithm. We then apply either Gaussian noise or Wishart noise to achieve joint-differentially private algorithms and bound the resulting algorithms' regrets. In addition, we give the first lower bound on the additional regret any private algorithms for the MAB problem must incur.


A Tree-Based Algorithm for Construction Robots

AAAI Conferences

In this paper, we present a tree-based algorithm for construction robots. Inspired by the TERMES project of Harvard University, robots in this domain are required to gather construction blocks from a reservoir and build user-specified structures much larger than themselves. While the robots are of roughly the same size as the blocks, they can scale greater heights by using temporarily constructed ramps in the substructures. In this paper, we consider the problem of minimizing the number of pickup and drop-off operations performed on blocks in order to build user-specified structures. Our polynomial-time algorithm heuristically solves this problem and is based on the idea of performing dynamic programming on a spanning tree in the inner loop and searching for a good tree to do so in the outer loop. Our algorithm performs very well in simulation and scales easily to large problem instances. For planning problems of this nature that are akin to construction domains, we believe that valuable lessons can be learned from comparing the success of our algorithm with the failure of off-the-shelf planning technologies.


A Tree-Based Algorithm for Construction Robots

AAAI Conferences

In this paper, we present a tree-based algorithm for construction robots. Inspired by the TERMES project of Harvard University, robots in this domain are required to gather construction blocks from a reservoir and build user-specified structures much larger than themselves. While the robots are of roughly the same size as the blocks, they can scale greater heights by using temporarily constructed ramps in the substructures. In this paper, we consider the problem of minimizing the number of pickup and drop-off operations performed on blocks in order to build user-specified structures. Our polynomial-time algorithm heuristically solves this problem and is based on the idea of performing dynamic programming on a spanning tree in the inner loop and searching for a good tree to do so in the outer loop. Our algorithm performs very well in simulation and scales easily to large problem instances. For planning problems of this nature that are akin to construction domains, we believe that valuable lessons can be learned from comparing the success of our algorithm with the failure of off-the-shelf planning technologies.