Category Archives: Machine Learning
Strategic Empathy for North Korea: The Intersection of Machine … – James Martin Center for Nonproliferation Studies
November 3, 2023
Why has the approach of the United States and its allies towards the North Korean nuclear weapons issue remained unfruitful for decades? Is our understanding of North Koreas worldview comprehensive and accurate? If not, what elements have been overlooked in our dealings with North Korea? Can we objectively discern reality and find a glimmer of hope for progress?
To address these questions through the lens of strategic empathy, CNS Research Fellow, Hyuk Kim, provides a unique seminar for policymakers to reevaluate their policies towards North Korea. Utilizing an unsupervised learning technique, Mr. Kim presents a visual representation of the global nuclear political landscape, illustrating the political alignment among United Nations Member States on nuclear issues. The quantitative analysis reveals unexpected outcomes, including a potential area for diplomatic cooperation with North Korea and surprising findings a reality some policymakers may find challenging to their assumptions. To interpret such anomalies, Hyuk Kim provides a qualitative analysis to help policymakers understand North Koreas worldview, drawing from Pyongyangs narratives at multilateral diplomatic venues. The seminar concludes with policy implications that paint a somewhat ambivalent picture of the complete denuclearization of the Korean Peninsula.
Chapters
00:00:00 Moderator: Robert Shaw, Director, Export Control and Nonproliferation Program of the James Martin Center for Nonproliferation Studies, Middlebury Institute of International Studies
00:05:30 Speaker: Hyuk Kim, Research Fellow, Export Control and Nonproliferation Program of the James Martin Center for Nonproliferation Studies, Middlebury Institute of International Studies
01:03:15 Q&A
On November 2nd, the Research Fellow of CNS, Mr. Hyuk Kim, delivered an insightful and though-provoking discourse on Strategic Empathy. Mr. Kim commenced the seminar by critically scrutinizing the inherent bias in policymakers worldviews, which are inevitably shaped by their environments. This predisposition often leads them to conflate their personal perspectives on global peace with the universally accepted viewpoint.
Throughout the seminar, Mr. Kim endeavored to find uniqueness from generalization in his analysis of the global nuclear political landscape. Through the quantitative analysis, Mr. Kim discerned the alignment of United Nations Member States on nuclear issues at large. Concurrently, his qualitative analysis unveiled the nuanced variations in the positions of seemingly aligned states on specific issue areas.
Mr. Hyuk Kim concluded the seminar by elucidating how the insights gleaned from the analytical process could illuminate our understanding of the Korean Peninsula. He underscored the significance of understanding North Koreas security concerns, thereby casting a new light on the crucial aspect of reassessing the prevailing policy towards North Korea.
Snowflake Accelerates How Users Build Next Generation Apps and Machine Learning Models in the Data Cloud – Yahoo Finance
Snowflake Notebooks unlock data exploration and machine learning development for SQL and Python users with an interactive, cell-based programming environment
Snowflake advances Snowpark to streamline end-to-end machine learning workflows with the Snowpark ML Modeling API, Snowpark Model Registry, Snowflake Feature Store, and more
Hundreds of Snowflake customers including Cybersyn, LiveRamp, and SNP are increasing developer productivity with the Snowflake Native App Framework and unlocking new revenue streams through Snowflake Marketplace
No-Headquarters/BOZEMAN, Mont., November 01, 2023--(BUSINESS WIRE)--Snowflake (NYSE: SNOW), the Data Cloud company, today announced at its Snowday 2023 event new advancements that make it easier for developers to build machine learning (ML) models and full-stack apps in the Data Cloud. Snowflake is enhancing its Python capabilities through Snowpark to boost productivity, increase collaboration, and ultimately speed up end-to-end AI and ML workflows. In addition, with support for containerized workloads and expanded DevOps capabilities, developers can now accelerate development and run apps all within Snowflake's secure and fully managed infrastructure.
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Snowflake Accelerates How Users Build Next Generation Apps and Machine Learning Models in the Data Cloud (Graphic: Business Wire)
"The rise of generative AI has made organizations most valuable asset, their data, even more indispensable. Snowflake is making it easier for developers to put that data to work so they can build powerful end-to-end machine learning models and full-stack apps natively in the Data Cloud," said Prasanna Krishnan, Senior Director of Product Management, Snowflake. "With Snowflake Marketplace as the first cross-cloud marketplace for data and apps in the industry, customers can quickly and securely productionize what theyve built to global end users, unlocking increased monetization, discoverability, and usage."
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Developers Gain Robust and Familiar Functionality for End-to-End Machine Learning
Snowflake is continuing to invest in Snowpark as its secure deployment and processing of non-SQL code, with over 35% of Snowflake customers using Snowpark on a weekly basis (as of September 2023). Developers increasingly look to Snowpark for complex ML model development and deployment, and Snowflake is introducing expanded functionality that makes Snowpark even more accessible and powerful for all Python developers. New advancements include:
Snowflake Notebooks (private preview): Snowflake Notebooks are a new development interface that offers an interactive, cell-based programming environment for Python and SQL users to explore, process, and experiment with data in Snowpark. Snowflakes built-in notebooks allow developers to write and execute code, train and deploy models using Snowpark ML, visualize results with Streamlit chart elements, and much more all within Snowflakes unified, secure platform.
Snowpark ML Modeling API (general availability soon): Snowflakes Snowpark ML Modeling API empowers developers and data scientists to scale out feature engineering and simplify model training for faster and more intuitive model development in Snowflake. Users can implement popular AI and ML frameworks natively on data in Snowflake, without having to create stored procedures.
Snowpark ML Operations Enhancements: The Snowpark Model Registry (public preview soon) now builds on a native Snowflake model entity and enables the scalable, secure deployment and management of models in Snowflake, including expanded support for deep learning models and open source large language models (LLMs) from Hugging Face. Snowflake is also providing developers with an integrated Snowflake Feature Store (private preview) that creates, stores, manages, and serves ML features for model training and inference.
Endeavor, the global sports and entertainment company that includes the WME Agency, IMG & On Location, UFC, and more, relies on Snowflakes Snowpark for Python capabilities to build and deploy ML models that create highly personalized experiences and apps for fan engagement.
"Snowpark serves as the driving force behind our end-to-end machine learning development, powering how we centralize and process data across our various entities, and then securely build and train models using that data to create hyper-personalized fan experiences at scale," said Saad Zaheer, VP of Data Science and Engineering, Endeavor. "With Snowflake as our central data foundation bringing all of this development directly to our enterprise data, we can unlock even more ways to predict and forecast customer behavior to fuel our targeted sales and marketing engines."
Snowflake Advances Developer Capabilities Across the App Lifecycle
The Snowflake Native App Framework (general availability soon on AWS, public preview soon on Azure) now provides every organization with the necessary building blocks for app development, including distribution, operation, and monetization within Snowflakes platform. Leading organizations are monetizing their Snowflake Native Apps through Snowflake Marketplace, with app listings more than doubling since Snowflake Summit 2023. This number is only growing as Snowflake continues to advance its developer capabilities across the app lifecycle so more organizations can unlock business impact.
For example, Cybersyn, a data-service provider, is developing Snowflake Native Apps exclusively for Snowflake Marketplace, with more than 40 customers running over 5,000 queries with its Financial & Economic Essentials Native App since June 2022. In addition, LiveRamp, a data collaboration platform, has seen the number of customers deploying its Identity Resolution and Transcoding Snowflake Native App through Snowflake Marketplace increase by more than 80% since June 2022. Lastly, SNP has been able to provide its customers with a 10x cost reduction in Snowflake data processing associated with SAP data ingestion, empowering them to drastically reduce data latency while improving SAP data availability in Snowflake through SNPs Data Streaming for SAP - Snowflake Native App.
With Snowpark Container Services (public preview soon in select AWS regions), developers can run any component of their app from ML training, to LLMs, to an API, and more without needing to move data or manage complex container-based infrastructure.
Snowflake Automates DevOps for Apps, Data Pipelines, and Other Development
Snowflake is giving developers new ways to automate key DevOps and observability capabilities across testing, deploying, monitoring, and operating their apps and data pipelines so they can take them from idea to production faster. With Snowflakes new Database Change Management (private preview soon) features, developers can code declaratively and easily templatize their work to manage Snowflake objects across multiple environments. The Database Change Management features serve as a single source of truth for object creation across various environments, using the common "configuration as code" pattern in DevOps to automatically provision and update Snowflake objects.
Snowflake also unveiled a new Powered by Snowflake Funding Program, innovations that enable all users to securely tap into the power of generative AI with their enterprise data, enhancements to further eliminate data silos and strengthen Snowflakes leading compliance and governance capabilities through Snowflake Horizon, and more at Snowday 2023.
Learn More:
Read more about how developers are building and deploying ML models with the latest Snowflake and Snowpark advancements in this blog post.
Learn more about how organizations can use Snowpark Container Services, Snowflake Native Apps, and Hybrid Tables to build, distribute, and operate full-stack apps on Snowflake in this blog post.
Read how Snowflake Cortex is providing customers with fast, easy, and secure LLM-powered app development in this blog post.
Explore whats new in Snowpark ML with this quickstart guide, and follow along the Snowpark ML docs page.
Ramp up on all things Snowflake Native Apps by signing up for the Snowflake Native App Bootcamp, and checking out this quickstart guide.
Stay on top of the latest news and announcements from Snowflake on LinkedIn and Twitter.
Forward Looking Statements
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Snowflake Accelerates How Users Build Next Generation Apps and Machine Learning Models in the Data Cloud - Yahoo Finance
A runoff prediction method based on hyperparameter optimisation of … – Nature.com
VMD-CEEMD decomposition algorithm
Variational Modal Decomposition (VMD) is an adaptive signal decomposition algorithm. It can decompose the signal into multiple components, and its essence and core idea is the construction and solution of the variational problem. VMD is commonly used to process non-linear signals and can decompose complex raw data to obtain a series of modal components16.
It can effectively extract the features of runoff data and reduce the influence of its nonlinearity and non-stationarity on the prediction results. The main steps of the VMD algorithm are: (1) The original signal is passed through the Hilbert transform to obtain a series of modal functions u, which are calculated to obtain the unilateral spectrum; (2) Transform the spectrum into the fundamental frequency band and construct the corresponding constrained variational problem by estimating the bandwidth; (3) Converting a constrained variational problem into an unconstrained variational problem17.
The calculated equations are as follows:
$$ L = left( {left{ {u_{k} } right},left{ {omega _{k} } right},lambda } right) = alpha mathop sum limits_{{k - 1}}^{K} left| {partial _{t} left[ {left( {delta left( t right) + frac{j}{{pi t}}} right)*u_{k} left( t right)} right]e^{{ - jomega _{t} t}} } right|_{2}^{2} + left| {fleft( t right) - mathop sum limits_{{k = 1}}^{K} u_{k} left( t right)} right|_{2}^{2} + left[ {lambda left( t right),fleft( t right) - mathop sum limits_{{k = 1}}^{k} u_{k} left( t right)} right], $$
(1)
where ({u}_{k}left(tright)) and ({omega }_{k}) are the modal components and the corresponding center frequencies, respectively, is the penalty function and is the Lagrange multiplier. The results of several experiments show that the decomposition results are better when is taken as 2000, so in this paper, is set to 2000. The k modal components of the VMD are solved by using the alternating direction method of multiplicative operators to find the saddle points of the unconstrained variational problem.
There are some potential features of the VMD decomposed runoff residual sequence. The CEEMD decomposition method is a new adaptive signal processing method. Compared with the commonly used EEMD method, its decomposition efficiency and reconstruction accuracy are higher, and it better exploits the potential features of residual sequences.
The EMD method is a method proposed by Huang et al. for signal time-domain decomposition processing, which is particularly suitable for the analysis of nonlinear and non-stationary time series18. In order to cope with the modal confusion problem of the EMD method, Wu et al.19 proposed an overall average empirical modal decomposition. The EEMD method effectively suppresses the modal aliasing caused by the EMD method by adding white noise to the original signal several times, followed by EMD decomposition, and averaging the EMD decomposed IMFs as the final IMFs20.
CEEMD by adding two Gaussian white noise signals with opposite values to the original signal, which are then subjected to separate EMD decompositions. In ensuring that the decomposition effect is comparable to that of EEMD, CEEMD reduces the reconstruction error induced by the EEMD method. After the original signal x(t) is decomposed by CEEMD, the reconstructed signal can be represented as
$$xleft(tright)=sum_{i=1}^{n}IM{F}_{i}left(tright)+{r}_{n}left(tright)$$
(2)
In Eq.(2), (IM{F}_{i}left(tright)) is the intrinsic modal function component; ({r}_{n}(t)) is the residual term; and n is the number of intrinsic modal components when ({r}_{n}(t)) becomes a monotonic function. The original sequence is finally decomposed into a finite number of IMFs.
In order to accurately predict the runoff sequence, this paper establishes a kernel limit learning machine prediction model based on the kernel function optimised by the nature-inspired BOA algorithm.
In Fig.1, the ELM input weights (omega in {R}^{XY}) (X and Y are the input and hidden layer neural networks, respectively) and biases are randomly generated21. Extreme learning machines require less manual tuning of parameters than BP neural networks, and can be trained on sample data in a shorter period of time, with fast learning rate and strong generalisation ability.
Structure of the KELM model.
Its regression function with output layer weights is:
$$left{begin{array}{c}fleft(xright)=h(x)beta =Hbeta \ {{varvec{H}}}^{T}{left(frac{1}{C}+{varvec{H}}{{varvec{H}}}^{T}right)}^{-1}Tend{array}right.$$
(3)
where: (fleft(xright))-model output; (x) -sample input ({varvec{h}}({varvec{x}})) and ({varvec{H}})-hidden layer mapping matrix; (beta ) -regularisation parameter; T-sample output vector.
Conventional ELM prediction models (solved by least squares) tend to destabilise the output when there is potential covariance in the sample parameters. Therefore, Huang et al.22 used the Kernel Extreme Learning Machine (KELM) with kernel function optimisation. Based on the kernel function principle, KELM can project covariant input samples into a high-dimensional space, which significantly improves the fitting and generalisation ability of the model. In addition, this model does not need to set the number of hidden layer nodes manually, reducing the number of spatial training bits and training time. The model output equation is:
$$fleft(xright)={left[begin{array}{c}K(x,{x}_{1})\ vdots \ K(x,{x}_{N})end{array}right]}^{T}{left(frac{1}{C}+{{varvec{Omega}}}_{ELM}right)}^{-1}$$
(4)
where: K(({x}_{i},{x}_{j}))-kernel function; ({{varvec{Omega}}}_{ELM})-kernel matrix, which is calculated as:
$$left{begin{array}{c}{{varvec{Omega}}}_{ELM}=H{{varvec{H}}}^{T}\ {{{varvec{Omega}}}_{ELM}}_{i,j}=hleft({x}_{i}right)hleft({x}_{j}right)=Kleft({x}_{i},{x}_{j}right)end{array}right.$$
(5)
where: ({x}_{i}) and ({x}_{j})-sample input vectors, i and j are taken as positive integers within [1,N]; K(({x}_{i},{x}_{j}))-kernel function.
KELM determines the implicit layer mapping kernel function in the form of an inner product by introducing a kernel function, and the number of implicit layer nodes does not need to be set; The result is faster model learning and effective improvement of the generalisation ability and stability of the KELM-based runoff prediction model.
Butterfly optimisation algorithm is an intelligent optimisation algorithm derived by simulating butterfly searching for food and mating behaviour23. In the BOA algorithm, each butterfly emits its own unique scent. Butterflies are able to sense the source of food in the air and likewise sense the scent emitted by other butterflies and move with the butterfly that emits a stronger scent, the scent concentration equation is:
where (f)Concentration of scent emitted by the butterfly, (c)Perceived morphology, (l)Stimulus intensity, (a)Power index, taken between [0,1]. When a=1, it means that the butterfly does not absorb the scent, meaning that the scent emitted by a specific butterfly is perceived by the same butterfly; This case is equivalent to a scent spreading in an ideal environment, where the butterfly emitting the scent can be sensed everywhere in the domain, and thus a single global optimum can be easily reached.
In order to prove the above with the search algorithm, the following hypothetical regulations were set up to idealise the characteristics of butterflies: (i) All butterflies can give off some scent, and butterflies attract and exchange information with each other by virtue of the scent. (ii) Butterflies undergo random movements or directional movements towards butterflies with strong scent concentrations.
By defining different fitness functions for different problems, the BOA algorithm can be divided into the following 3 steps:
Step 1: Initialisation phase. Randomly generate butterfly locations in the search space, calculate and store each butterfly location and fitness value.
Step 2: Iteration phase. Multiple iterations are performed by the algorithm, in each iteration the butterflies are moved to a new position in the search space and then their fitness values are recalculated. The adaptation values of the randomly generated butterfly population are sorted to find the best position of the butterfly in the search space.
Step 3: End Phase, In the previous phase, the butterflies move and then use the scent formula to produce a scent in a new location.
The penalty parameter C and the kernel function parameter K in the kernel-limit learning machine are chosen as the searching individuals of the butterfly population, and the BOA-KELM model is constructed to achieve the iterative optimisation of C and K. The specific steps are as follows:
Step 1: Collect runoff data and produce training and prediction sample sets.
Step 2: Initialise the butterfly population searching individuals i.e. penalty parameter C and kernel function parameter K.
Step 3: Initialise the algorithm parameters, including the number of butterfly populations M, the maximum number of iterations .
Step 4: Calculate the fitness value of the individual butterfly population and calculate the scent concentration f. Based on the fitness value, the optimal butterfly location is derived.
Step 5: Check the fitness value of the butterfly population searching individuals after updating their positions, determine whether it is better than before updating, and update the global optimal butterfly position and fitness value.
Step 6:Judge whether the termination condition is satisfied. If it is satisfied, exit the loop and output the prediction result; otherwise, bring in the calculation again.
Step 7:Input the test set into the optimised KELM and output the predictions.
According to the above steps, the corresponding flowchart is shown in Fig.2.
BOA Optimisation KELM Model Flowchart.
In order to improve the accuracy of runoff prediction, this paper designs a runoff prediction framework based on the idea of "decompositionmodeling predictionreconstruction", as shown in Fig.3, and the specific prediction steps are as follows:
VMD-CEEMD-BOA-KELM prediction model framework.
Step 1: Data pre-processing. Anomalies in the original runoff series were processed using the Lajda criterion.
Step 2: VMD-CEEMD decomposition. The raw runoff series was decomposed using the VMD algorithm, and then the data was decomposed quadratically using the CEEMD algorithm to obtain k components.
Step 3: Data preparation. Each component is normalised and divided into a training data set and a test data set.
Step 4: Modelling prediction. A BOA-optimised KELM model is built based on the training dataset for each component and predicted for the test dataset.
Step 5: Reconstruction. The predictions of all components are accumulated to obtain the prediction of the original runoff sequence.
In order to reflect the error and prediction accuracy of the model prediction results more clearly, four indicators, RMSE, MAE, R2, and NSE are used for the analysis, and the equations are calculated as follows:
$${varvec{R}}{varvec{M}}{varvec{S}}{varvec{E}}=sqrt{frac{1}{{varvec{N}}}cdot {sum }_{{varvec{i}}=1}^{{varvec{N}}}{left({{varvec{y}}}_{{varvec{i}}}-{{varvec{y}}}_{{varvec{c}}}right)}^{2}}$$
$${varvec{M}}{varvec{A}}{varvec{E}}=frac{1}{{varvec{N}}}cdot {sum }_{{varvec{i}}=1}^{{varvec{N}}}left|{{varvec{y}}}_{{varvec{i}}}-{{varvec{y}}}_{{varvec{c}}}right|$$
$${{varvec{R}}}^{2}={left[frac{sum left({{varvec{y}}}_{{varvec{i}}}-overline{{{varvec{y}} }_{{varvec{i}}}}right)left({{varvec{y}}}_{{varvec{c}}}-overline{{{varvec{y}} }_{{varvec{c}}}}right)}{sqrt{sum {left({{varvec{y}}}_{{varvec{i}}}-overline{{{varvec{y}} }_{{varvec{i}}}}right)}^{2}}sum {left({{varvec{y}}}_{{varvec{c}}}-overline{{{varvec{y}} }_{{varvec{c}}}}right)}^{2}}right]}^{2}$$
$${varvec{N}}{varvec{S}}{varvec{E}}=1-frac{{sum }_{{varvec{t}}=1}^{{varvec{T}}}{left({{varvec{y}}}_{{varvec{i}}}-{{varvec{y}}}_{{varvec{c}}}right)}^{2}}{{sum }_{{varvec{t}}=1}^{{varvec{T}}}{left({{varvec{y}}}_{{varvec{i}}}-overline{{{varvec{y}} }_{{varvec{i}}}}right)}^{2}}$$
This paper does not contain any studies with human participants or animals performed by any of the authors.
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A runoff prediction method based on hyperparameter optimisation of ... - Nature.com
Probabilistic source classification of large tephra producing … – United States Geological Survey (.gov)
Alaska contains over 130 volcanoes and volcanic fields that have been active within the last 2 million years. Of these, roughly 90 have erupted during the Holocene, with many characterized by at least one large explosive eruption. These large tephra-producing eruptions (LTPEs) generate orders of magnitude more erupted material than a typical arc explosive eruption and distribute ash thousands of kilometers from their source. Because LTPEs occur infrequently, and the proximal explosive deposit record in Alaska is generally limited to the Holocene, we require a method that links distal deposits to a source volcano where the correlative proximal deposits from that eruption are no longer preserved. We present a model that accurately and confidently identifies LTPE volcanic sources in the Alaska-Aleutian arc using only in situ geochemistry. The model is a voting ensemble classifier comprised of six conceptually different machine learning algorithms trained on proximal tephra deposits that have had their source positively identified. We show that incompatible trace element ratios (e.g., Nb/U, Th/La, Rb/Sm) help produce a feature space that contains significantly more variance than one produced by major element concentrations, ultimately creating a model that can achieve high accuracy, precision, and recall on predicted volcanic sources, regardless of the perceived 2D data distribution (i.e., bimodal, uniform, normal) or composition (i.e., andesite, trachyte, rhyolite) of that source. Finally, we apply our model to unidentified distal marine tephra deposits in the region to better understand explosive volcanism in the Alaska-Aleutian arc, specifically its pre-Holocene spatiotemporal distribution.
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Probabilistic source classification of large tephra producing ... - United States Geological Survey (.gov)
Predicting Conversion to Psychosis Using Machine Learning: Are … – Am J Psychiatry
In the present issue of the American Journal of Psychiatry, Smucny et al. suggest that predictive algorithms for psychosis using machine learning (ML) methods may already achieve a clinically useful level of accuracy (1). In support of this perspective, these authors report on the results of an analysis using the North American Prodrome Longitudinal Study, Phase 3 (NAPLS3) data set (2), which they accessed through the National Institute of Mental Health Data Archive (NDAR). This is a large multisite study of youth at clinical high risk for psychosis followed up on multiple occasions with clinical, cognitive, and biomarker assessments. Several ML approaches were compared with each other and with Cox (time-to-event) and logistic regression using the clinical, neurocognitive, and demographic features from the NAPLS2 individualized risk calculator (3), with salivary cortisol also tested as an add-on biomarker. When these variables were analyzed using Cox and logistic regression, the model applied to the NAPLS3 cohort attained a level of predictive accuracy comparable to that observed in the original NAPLS2 cohort (overall accuracy in the 66%68% range). However, several ML algorithms produced nominally better results, with a random forest model performing best (overall accuracy in the 90% range). Acknowledging that a predictive algorithm with 90% or higher predictive accuracy will have greater clinical utility than one with substantially lower accuracy, several issues remain to be resolved before it can be determined whether ML methods have attained this utility threshold.
First and foremost, an ML models expected real-world performance can only be ascertained when tested in an independent sample/data set that the model has never before encountered. ML methods are very adept at finding apparent structure in data that predict an outcome, but if that structure is idiosyncratic to the training data set, the model will fail to generalize to other contexts and thus not be useful, a problem known as overfitting (4). Internal cross-validation methods are not sufficient to overcome this problem, since the model sees all the training data at certain points in the process, even if some is left out on a particular iteration (5). Overfitting is indicated by a big drop-off in model accuracy moving from the original internally cross-validated training data set to an external, independent cross-validation test. Smucny et al. (1) acknowledge the need for an external replication test before the utility of the ML models they evaluated using only internal cross-validation methods can be fully appreciated.
Is there likely to be a big drop-off in accuracy of the ML models reported by Smucny et al. (1) when such an external validation test is performed? On one hand, they limited consideration to a small number of features that have previously been shown to predict psychosis in numerous independent samples (i.e., the variables in the NAPLS2 risk calculator [3]). This aspect mitigates the overfitting issue to some extent because the features used in model building are already filtered (based on prior work) to be highly likely to predict conversion to psychosis, both individually and when combined in a regression model. On the other hand, the ML models employed in the study use various approaches to find higher-order interactive and nonlinear amalgamations among this set of feature variables that maximally discriminate outcome groups. This aspect increases the risk of overfitting given that a very large number of such higher-order interactive effects are assessed in model building, with relatively few subjects available to represent each unique permutation, a problem known as the curse of dimensionality (6). Tree-based methods such as the random forest model that performed best in the NAPLS3 data set are not immune from this problem and, in fact, are particularly vulnerable to it when applied on data sets with relatively small numbers of individuals with the outcome of interest (7).
The relatively low base rate of conversion to psychosis (i.e., 10%15%), even in a sample selected to be at elevated risk as in NAPLS3, creates another problem for ML methods; namely, such models can achieve high levels of predictive accuracy in the training data set simply by guessing that each case is a nonconverter. Smucny et al. (1) attempt to overcome this issue using a synthetic approach that effectively up samples the minority class (in this case, converters to psychosis) to the point that it has 50% representation in the synthetic sample (8). Although this approach is very helpful in preventing ML models from defaulting to prediction of a majority class, its use in computing cross-validation performance metrics is likely to be highly misleading, given that real-world application of the model is not likely to occur in a context in which there is a 50:50 rate of future converters and nonconverters. Rather, the model will be applied in circumstances in which new clinical high risk (CHR) individuals likelihoods of conversion are computed, and those CHR individuals will derive from a population in which the base rate of conversion is 15%. It is now well established that the same predictive model will result in different risk distributions (and, thereby, different thresholds in model-predicted risk for making binary predictions) in samples that vary in base rates of conversion to psychosis (9). Given this, a 90% predictive accuracy of an ML algorithm in a synthetically derived sample in which the base rate of psychosis conversion is artificially created to be 50% is highly unlikely to generalize to an independent, real-world CHR sample, at least as ascertained using current approaches.
When developing the NAPLS2 risk calculator, the investigators made purposeful decisions to allow the resulting algorithm to be applied validly in scaling the risk of newly ascertained CHR individuals (3). Key among these decisions was to avoid using the NAPLS2 data set to test different possible models, which would then necessitate an external validation test. Rather, a small number of predictor variables was chosen based on their empirical associations with conversion to psychosis in prior studies, and Cox regression was employed to generate an additive multivariate model of predicted risk (i.e., no interactive or non-linear combinations of the variables were included). As a result, the ratio of converters to predictor variables was 10:1 (helping to create adequate representation of the scale values of each predictor in the minority class), and there was no need to use a synthetic sampling approach given that Cox regression is well suited for prediction of low base rate outcomes. The predictor variables chosen for inclusion are ones that are easily ascertained in standard clinical settings and have a high level of acceptability (face validity) for use in clinical decision making. It is important to note that the NAPLS2 model has been shown to replicate (in terms of area under the curve or concordance index) when applied to multiple external independent data sets (10).
Nevertheless, two issues continue to limit the utility of the NAPLS2 risk calculator. One is that it will generate differently shaped risk distributions on samples that vary in conversion risk and in distributions of the individual predictor variables, making it problematic to apply the same threshold of predicted risk for binary predictions across samples that differ in these ways (9, 11). However, it appears possible to derive comparable prediction metrics across samples with differing conversion risks when considering the relative recency of onset or worsening of attenuated positive symptoms at the baseline assessment (11). A more recent onset or worsening of attenuated positive symptoms defines a subgroup of CHR individuals with a higher average predicted risk and higher overall transition rate and in whom particular putative illness mechanisms, in this case an accelerated rate of cortical thinning (12), appear to be differentially relevant (11).
The second rate-limiting issue for the utility of the NAPLS2 risk calculator is that its performance in terms of sensitivity, specificity, and balanced accuracy, even when accounting for recency of onset of symptoms, is still in the 65%75% range. Although ML methods represent one approach that, if externally validated, could conceivably result in predictive models at the 90% or higher level of accuracy, such models would continue to have the disadvantage of being relatively opaque (black box) in terms of how the underlying predictor variables aggregate in defining risk and for that reason may not be used as readily in clinical practice. Alternatively, it may be possible to rely on more transparent analytic approaches to achieve the needed level of accuracy. It has recently been demonstrated that integrating information on short-term (baseline to 2-month follow-up) change on a single clinical variable (e.g., deterioration in odd behavior/appearance) improves the performance of the NAPLS2 risk calculator to >90% levels of sensitivity, specificity, and balanced accuracy; i.e., a range that would support its use in clinical trial design and clinical decision-making (13). Importantly, although the Cox regression model aspect of this algorithm has been externally validated, the incorporation of short-term clinical change (via mixed effects growth modeling) requires replication in an external data set.
Smucny et al. (1) are to be congratulated on a well-motivated and well-executed analysis of the NAPLS3 data set. It is heartening to see such creative uses of this unique shared resource for our field bear fruit, reinforcing the value of open science. As we move forward toward the time and place in which prediction models of psychosis and related outcomes have utility for clinical decision making, whether those models rely on machine learning methods or more traditional approaches, it will be crucial to insist on external validation of results before deciding that we are, in fact, there.
Clark L. Hull Professor of Psychology and Professor of Psychiatry, Yale University, New Haven, Conn.
Dr. Cannon reports no financial relationships with commercial interests.
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Predicting Conversion to Psychosis Using Machine Learning: Are ... - Am J Psychiatry
Watch: Peter Jackson discusses the machine learning technology … – TVBEurope
A 12-minute documentary provides insight into Now and Then's creation, and includes both archive and current-day footage
By Jenny Priestley
To mark the release of whats being called the last song from The Beatles, the band has also unveiled a documentary about how the song was put together using 21st-century technology.
The documentary, directed by Oliver Murray with sound design by Alastair Sirkett, provides insight into Now and Thens creation, and includes both archive and current-day footage.
It features an interview with director Peter Jackson, whose WingNut Films used MAL software to extract John Lennons voice from the original cassette recording.
During the course of Get Back we were paying a lot of attention to the technical restoration, explains Jackson.
That ultimately led us to develop a technology which allows us to take any soundtrack and split all the different components into separate tracks based on machine learning.
Jenny has worked in the media throughout her career, joining TVBEurope as editor in 2017. She has also been an entertainment reporter, interviewing everyone from Kylie Minogue to Tom Hanks; as well as spending a number of years working in radio. She continues to appear on radio every week and occasionally pops up on TV.
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Watch: Peter Jackson discusses the machine learning technology ... - TVBEurope
Explore AI Careers in the United States: Apply Today – Analytics Insight
Learn about and apply for artificial intelligence careers in the United States
Artificial intelligence (AI) is one of the most rapidly growing and in-demand fields in the United States, with job openings expected to grow 33% by 2030, much faster than the average for all occupations. AI careers offer competitive salaries, exciting opportunities to work on cutting-edge technologies, and the chance to make a real impact on the world. In this article lets explore the available AI careers in the United States.
Role: AI/ML Developer
Qualifications: Expertise in Python libraries for machine learning, natural language processing, image preprocessing, and databases, as well as experience with machine learning toolkits and frameworks, deep learning concepts, and applying ML algorithms effectively.
Responsibilities: Design, develop, and train machine learning systems to optimize performance and build self-learning applications. Stay up-to-date with the latest developments in the field and use GPU, pyspark, and parallel compute libraries in Python. Understand how components and processes work together using library calls, REST APIs, queueing/messaging systems, and database queries. Design systems to avoid bottlenecks and scale well with increasing volumes of data.
Link to apply
Role: AI/ML EngineerQualifications: Data science, statistics, or machine learning education, with strong programming skills in Python, R, or Java. Experience with machine learning frameworks and setting up machine learning problem spaces and solutions. Ability to evaluate the performance and efficacy of machine learning solutions and interest in advanced machine learning concepts.
Responsibilities: Collaborate with data scientists, machine learning engineers, software engineers, and QA engineers to explore and prototype data and machine learning opportunities. Design, develop, test, and support services to deploy resulting models and cognitive solutions in production.
Link to apply
Role: Machine Learning Researcher
Qualifications: 3+ years of experience in machine learning for computer vision applications, with a strong understanding of machine learning algorithms and a proven track record of developing and deploying high-quality computer vision algorithms. Excellent software design, problem-solving, and debugging skills. Fluency in Python and another language (C/C++, Go, Rust), as well as experience with relevant deep learning software packages. Great technical skills, a drive for high-quality software, and the ability to innovate creative solutions. Excellent communication and the flexibility to learn new technologies.
Responsibilities: Youll be involved in all stages of model development, from data analysis and prototyping to testing and deployment.
Link to apply
Role: AI Research Scientist
Qualifications: Masters degree in Electrical Engineering, Computer Engineering, Computer Science, or related field, with 3+ years of experience in neural architecture search (NAS) and machine learning for training deep neural networks.
Responsibilities: This role is available as a fully home-based and generally would require you to attend Intel sites only occasionally based on their business need. This role may also be available as our hybrid work model which allows employees to split their time between working on-site at their assigned Intel site and off-site. In certain circumstances, the work model may change to accommodate business needs.
Link to apply
Role: Senior Artificial Intelligence Scientist
Qualifications: Experience in machine learning research, evidenced by at least one first-author publication in a scientific journal, or equivalent, and experience with search and/or optimization-based sequence design algorithms.
Responsibilities: You will join a growing team of AI/ML experts and work closely with scientists across gRED to develop and deploy machine learning methods for the analysis of single-cell genomics datasets and biological sequences. You will help build and scale machine learning techniques to handle massive datasets and deploy novel machine learning algorithms.
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Explore AI Careers in the United States: Apply Today - Analytics Insight
WiMi Announced a Multi-View Hybrid Recommendation Model … – AiThority
WiMi Hologram Cloud Inc.a leading global Hologram Augmented Reality (AR) Technology provider, announced that a deep learning-based multi-view hybrid recommendation model was developed. This model can consider multiple views and information sources simultaneously to capture the relationship between users and items more comprehensively. By fusing features from different views, the multi-view hybrid recommendation model can provide more accurate and personalized recommendation results.
The significance of the multi-view hybrid recommendation model lies in the ability to synthesize information from different views to gain a more comprehensive understanding of the users interests and preferences. For example, user behavior data can reflect the users historical behavior and preferences, social network data can reflect the users social relationships and social influence, and content data can reflect the attributes and characteristics of items. By combining information from these different views, we can more accurately predict users interests, improve the accuracy and personalization of the recommendation system, and at the same time solve the data sparsity and cold-start problems so as to provide better recommendation results.
Recommended AI News:Riding on the Generative AI Hype, CDP Needs a New Definition in 2024Deep learning is utilized in WiMis deep learning-based multi-view hybrid recommendation system for feature learning and recommendation model construction. Feature learning refers to the automatic learning of user and item representations through deep neural networks, so that user interests and item characteristics can be better captured. Recommendation model construction, on the other hand, refers to applying the learned features to specific recommendation tasks, such as user behavior-based recommendation, content-based recommendation, and so on. Commonly used models for the application of deep learning in recommendation systems include matrix decomposition-based models, convolutional neural network-based models, recurrent neural network-based models, and so on. These models make recommendations by learning user and item representations and combining user behavior and item features.
In a multi-view hybrid recommendation model, we need to consider information from multiple views (e.g., user behavior, item attributes, social networks, etc.) to make recommendations. The details of the deep learning-based multi-view hybrid recommendation model developed by WiMi are as follows:
Input layer: Firstly, the feature representation of each view is used as the input to the model, for each view, we use different feature extraction methods, for example, for the user behavior view, we can use the users click record as the feature; for the item attribute view, we can use the items attribute vector as the feature.
View feature integration layer: In this layer, we integrate the features of different views, and can use some integration methods to fuse the information of different views together to get a more comprehensive feature representation.
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Feature encoding layer: The integrated features are encoded using deep learning models (e.g., neural networks). This maps the high-dimensional features to a low-dimensional representation space and extracts more useful features.
Feature interaction layer: The encoded features interact with each other, and some interaction methods can be used, such as dot product and weighted summation, so that the interactions between different features can be captured and the expressive power of the model can be improved.
Output layer: Using some output layer methods such as a fully connected layer, softmax, etc., the features are mapped to a probability distribution of the recommendation results, so that a recommendation result can be obtained for each user.
With the above model layers, the information from multiple views can be fully utilized to improve the accuracy and personalization of recommendations. At the same time, the model is also highly scalable and it is easy to add new views or adjust the model structure.
With the popularization of the Internet and mobile Internet, the application scenarios of recommendation systems are becoming more and more extensive, such as e-commerce, news reading, music recommendation and so on. At the same time, with the continuous development of data collection and storage technology, the available data types and quantities are also increasing, which provides a broader space for the development of recommendation systems.
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The WiMis deep learning-based multi-view hybrid recommendation model utilizes deep learning techniques to combine information from multiple views or perspectives to construct a comprehensive recommendation model approach, which can comprehensively utilize multiple types of data to provide more accurate and personalized recommendation services, and can also adaptively adjust the recommendation strategy so as to improve the recommendation effect and user satisfaction.
[To share your insights with us, please write tosghosh@martechseries.com]
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WiMi Announced a Multi-View Hybrid Recommendation Model ... - AiThority
SandBox Semiconductor to present at the AVS International … – EE Journal
AUSTIN, TX November 7, 2023 SandBox Semiconductor, a pioneer in applying physics-based, AI-enabled modeling to accelerate the development of semiconductor manufacturing processes, will participate in the2023 AVS International Symposium and Exhibitiontaking place November 5-10, 2023 at the Oregon Convention Center in Portland, OR. Dr. Sebastian Naranjo, Computational Engineer at SandBox Semiconductor will give a presentation on Thursday discussing how advances in machine learning, analysis, and visualization technology are helping to accelerate recipe and process modeling optimization in semiconductor manufacturing.
The fact that AVS is dedicating a full session to AI and machine learning is a testament to the growing importance of technology in the semiconductor manufacturing process, said Dr. Meghali Chopra, SandBox Semiconductor CEO & Co-founder. Were looking forward to discussing how it can be applied to recipe optimization for deposition to accelerate process development, get new products to market faster, and reduce costs.
WHO: Dr. Sebastian Naranjo, Computational Engineer,SandBox Semiconductor
WHAT:Rapid Optimization of Gap-Fill Recipes Using Machine Learning
WHEN: Thursday, November 9, 2023 at 3:40 pm PT
WHERE: Oregon Convention Center, 777 NE Martin Luther King Jr Blvd, Portland, OR 97232
WHY: Semiconductor manufacturing is a complicated process that involves up to 1,200 steps. Currently, process development for each unit process is performed sequentially, one step after another. SandBox Studio AI combines physics-based modeling with AI to allow engineers to streamline process development to shrink timelines and decrease dependency on extensive physical experiments. The AVS presentation will discuss how machine learning can enable process engineers to co-optimize multiple unit processes at a time and dramatically alleviate the cost, time and complexity issues associated with recipe development. The presentation focuses on a gap-fill process flow.
About SandBox Semiconductor
Founded in 2016, SandBox Semiconductor is a pioneer in developing AI based software to accelerate process development for semiconductor manufacturing. Its fully integrated no-code AI tool suite gives process engineers the ability to build their own physics-based, AI-enabled models to solve challenges during process definition, ramp-up, and high-volume manufacturing.
Using SandBoxs physics-based models and machine learning tools, engineers can virtually simulate, predict, and measure process outcomes. Even with small sets of experimental data, SandBoxs tools can extract valuable insights and patterns, helping engineers to gain a deeper understanding of manufacturing processes and to make informed decisions about recipe adjustments. SandBox leverages expertise in numerical modeling, machine learning, and manufacturing optimization to develop its proprietary toolsets, which are used by the worlds leading chip manufacturers and semiconductor equipment suppliers. SandBox is based in Austin, Texas. More information can be found here:www.sandboxsemiconductor.com.
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SandBox Semiconductor to present at the AVS International ... - EE Journal