shih
Conformal calibration and look-elsewhere effect in anomaly detection for new-physics searches
Araz, Jack Y., Spannowsky, Michael
Machine-learned anomaly detection is reshaping searches for new physics, but it has outrun the statistics used to interpret it. A raw anomaly score has no calibrated meaning, a model that scans many regions inflates the look-elsewhere effect, and the asymptotic significances the field relies on are blind to the background mismodelling that anomaly detectors are especially prone to. We propose a calibration layer, built on conformal prediction, that turns any anomaly score into a defensible significance with distribution-free, finite-sample guarantees. Conformal prediction converts scores into valid local p-values, weighted and Mondrian variants repair the sideband-to-signal-region exchangeability failures that resonant searches suffer, and a Gross-Vitells step carries the result through to a look-elsewhere-aware global significance. The layer does two things at once. It exposes miscalibration that the standard pipeline cannot see, and it corrects it without retraining the detector. On public LHC Olympics data, a classifier develops a substructure-mass correlation that makes sideband-calibrated background p-values anti-conservative. Taken at face value, this manufactures a $\sim 46ฯ$ excess from background sculpting alone, which the label-free weighted correction removes, restoring an honest null. When run as a blind wide-mass bump hunt, the standard asymptotic and unweighted procedures fabricate $\gtrsim10ฯ$ excesses and $\approx5ฯ$ excesses even in signal-free windows, while the conformal layer raises no false alarms and its global false-positive rate is verified on background-only pseudoexperiments. The result is an auditable, detector-agnostic path from an uncalibrated score to a trials-factor-aware significance, ready to be folded into experimental anomaly searches.
Women Business Leaders on How To Solve AI's Inclusivity Problem
Follow this author to personalize your feed and get instant alerts. Follow Go to your personalized feed WHY FOLLOW? Smart Alerts: Get notified about major news as it happens. When Julie Kim takes over as CEO of pharmaceutical giant Takeda in June, she says she will be proud to be known as the first woman and Korean American to ever lead the company. "If you would have asked me 20-30 years ago, I would have said, 'I want to be known as a good leader, or a good business woman, or a good strategist without those labels," she said.
SIGMA: Single Interpolated Generative Model for Anomalies
A key step in any resonant anomaly detection search is accurate modeling of the background distribution in each signal region. Data-driven methods like CATHODE accomplish this by training separate generative models on the complement of each signal region, and interpolating them into their corresponding signal regions. Having to re-train the generative model on essentially the entire dataset for each signal region is a major computational cost in a typical sliding window search with many signal regions. Here, we present SIGMA, a new, fully data-driven, computationally-efficient method for estimating background distributions. The idea is to train a single generative model on all of the data and interpolate its parameters in sideband regions in order to obtain a model for the background in the signal region. The SIGMA method significantly reduces the computational cost compared to previous approaches, while retaining a similar high quality of background modeling and sensitivity to anomalous signals.
High-dimensional and Permutation Invariant Anomaly Detection
Mikuni, Vinicius, Nachman, Benjamin
Methods for anomaly detection of new physics processes are often limited to low-dimensional spaces due to the difficulty of learning high-dimensional probability densities. Particularly at the constituent level, incorporating desirable properties such as permutation invariance and variable-length inputs becomes difficult within popular density estimation methods. In this work, we introduce a permutation-invariant density estimator for particle physics data based on diffusion models, specifically designed to handle variable-length inputs. We demonstrate the efficacy of our methodology by utilizing the learned density as a permutation-invariant anomaly detection score, effectively identifying jets with low likelihood under the background-only hypothesis. To validate our density estimation method, we investigate the ratio of learned densities and compare to those obtained by a supervised classification algorithm.
Residual ANODE
Das, Ranit, Kasieczka, Gregor, Shih, David
We present R-ANODE, a new method for data-driven, model-agnostic resonant anomaly detection that raises the bar for both performance and interpretability. The key to R-ANODE is to enhance the inductive bias of the anomaly detection task by fitting a normalizing flow directly to the small and unknown signal component, while holding fixed a background model (also a normalizing flow) learned from sidebands. In doing so, R-ANODE is able to outperform all classifier-based, weakly-supervised approaches, as well as the previous ANODE method which fit a density estimator to all of the data in the signal region instead of just the signal. We show that the method works equally well whether the unknown signal fraction is learned or fixed, and is even robust to signal fraction misspecification. Finally, with the learned signal model we can sample and gain qualitative insights into the underlying anomaly, which greatly enhances the interpretability of resonant anomaly detection and offers the possibility of simultaneously discovering and characterizing the new physics that could be hiding in the data.
Boosting-based Construction of BDDs for Linear Threshold Functions and Its Application to Verification of Neural Networks
Tang, Yiping, Hatano, Kohei, Takimoto, Eiji
Understanding the characteristics of neural networks is important but difficult due to their complex structures and behaviors. Some previous work proposes to transform neural networks into equivalent Boolean expressions and apply verification techniques for characteristics of interest. This approach is promising since rich results of verification techniques for circuits and other Boolean expressions can be readily applied. The bottleneck is the time complexity of the transformation. More precisely, (i) each neuron of the network, i.e., a linear threshold function, is converted to a Binary Decision Diagram (BDD), and (ii) they are further combined into some final form, such as Boolean circuits. For a linear threshold function with $n$ variables, an existing method takes $O(n2^{\frac{n}{2}})$ time to construct an ordered BDD of size $O(2^{\frac{n}{2}})$ consistent with some variable ordering. However, it is non-trivial to choose a variable ordering producing a small BDD among $n!$ candidates. We propose a method to convert a linear threshold function to a specific form of a BDD based on the boosting approach in the machine learning literature. Our method takes $O(2^n \text{poly}(1/\rho))$ time and outputs BDD of size $O(\frac{n^2}{\rho^4}\ln{\frac{1}{\rho}})$, where $\rho$ is the margin of some consistent linear threshold function. Our method does not need to search for good variable orderings and produces a smaller expression when the margin of the linear threshold function is large. More precisely, our method is based on our new boosting algorithm, which is of independent interest. We also propose a method to combine them into the final Boolean expression representing the neural network.
Why ChatGPT and AI are taking over the cold call, according to Salesforce leader
Generative artificial intelligence tools like ChatGPT are changing the way that companies and salespeople are communicating with customers for the better, said Clara Shih, CEO of Salesforce's Service Cloud business. "You look at how salespeople work today, and most of them, they dread writing sales emails; they'd much rather be out there with customers," Shih said on CNBC's "Squawk Box" on Thursday. "So they can offload those tasks that are more mundane โฆ they want to focus on engaging with the customer and problem solving." Shih drew a clear line between how generative AI can be utilized by the general person compared to business clients and enterprise users: "We're not talking about writing funny poems, we're talking about writing sales emails and customer service responses that agents can send to get back to customers faster." Earlier this week, Salesforce launched what it called the first generative AI CRM technology, Einstein GPT.
Part Four: Intended & Unintended Uses -- Artificial Intelligence -- Voice Assistants
The need for improvement has been changing the world for thousands of years. Numerous inventions have filled gaps with intended and unintended uses in response to this desire for advancement. Take the wheel, for example. It was developed to assist potters with their clay back in Mesopotamia around 3500 B.C. (Gambino, 2009). Now, we get thousands of different uses out of the wheel.
On Tractable Representations of Binary Neural Networks
Shi, Weijia, Shih, Andy, Darwiche, Adnan, Choi, Arthur
We consider the compilation of a binary neural network's decision function into tractable representations such as Ordered Binary Decision Diagrams (OBDDs) and Sentential Decision Diagrams (SDDs). Obtaining this function as an OBDD/SDD facilitates the explanation and formal verification of a neural network's behavior. First, we consider the task of verifying the robustness of a neural network, and show how we can compute the expected robustness of a neural network, given an OBDD/SDD representation of it. Next, we consider a more efficient approach for compiling neural networks, based on a pseudo-polynomial time algorithm for compiling a neuron. We then provide a case study in a handwritten digits dataset, highlighting how two neural networks trained from the same dataset can have very high accuracies, yet have very different levels of robustness. Finally, in experiments, we show that it is feasible to obtain compact representations of neural networks as SDDs.
Why We Should Stop Worrying About A.I. (And Start Worrying About Data)
The one-two punch of data and artificial intelligence are in the midst of transforming the world as we know it. But how do we make sure that the new world that emerges in their wake is one we'll want to live in? A big part of the equation is ensuring that consumers' data is handled properly. Speaking on a panel at Fortune's Most Powerful Women Summit in Laguna Niguel, Calif. on Monday, Clara Shih, CEO and co-founder of Hearsay Systems, offered a straight-forward, four-point system for doing just that: Let people know what information will be used and how. Be clear about when people can opt in or out of having their personal data collected.