Oceania
'A long road': the Australian city aiming to give self-driving cars the green light
As the traffic lights turn from amber to red, Miranda Blogg accelerates towards them. "Here we go," she says. A dash-mounted screen in her Renault ZOE flashes a warning featuring a traffic light symbol. The screen erupts with a more aggressive visual display ("Stop!") accompanied by three loud, grating, beeps. "Whoops," she says, as she brakes, still well ahead of the lights.
Data Engineer/ETL Developer
Total Brain is a digital neurotechnology platform. We leverage digital technology, neuroscience, and biometrics to help individuals monitor and support their mental health and wellness. The company was founded by Dr Evian Gordon, Md, PhD in 2000. It is headquartered in San Francisco but staff are largely decentralized across the US and Sydney Australia where the company was publicly listed 20 years ago. We offer our platform and value proposition to enterprise employers, large consumer groups and mental health clinicians and clinics.
NCoRE: Neural Counterfactual Representation Learning for Combinations of Treatments
Parbhoo, Sonali, Bauer, Stefan, Schwab, Patrick
Estimating an individual's potential response to interventions from observational data is of high practical relevance for many domains, such as healthcare, public policy or economics. In this setting, it is often the case that combinations of interventions may be applied simultaneously, for example, multiple prescriptions in healthcare or different fiscal and monetary measures in economics. However, existing methods for counterfactual inference are limited to settings in which actions are not used simultaneously. Here, we present Neural Counterfactual Relation Estimation (NCoRE), a new method for learning counterfactual representations in the combination treatment setting that explicitly models cross-treatment interactions. NCoRE is based on a novel branched conditional neural representation that includes learnt treatment interaction modulators to infer the potential causal generative process underlying the combination of multiple treatments. Our experiments show that NCoRE significantly outperforms existing state-of-the-art methods for counterfactual treatment effect estimation that do not account for the effects of combining multiple treatments across several synthetic, semi-synthetic and real-world benchmarks.
On Subspace Approximation and Subset Selection in Fewer Passes by MCMC Sampling
Deshpande, Amit, Pratap, Rameshwar
We consider the problem of subset selection for $\ell_{p}$ subspace approximation, i.e., given $n$ points in $d$ dimensions, we need to pick a small, representative subset of the given points such that its span gives $(1+\epsilon)$ approximation to the best $k$-dimensional subspace that minimizes the sum of $p$-th powers of distances of all the points to this subspace. Sampling-based subset selection techniques require adaptive sampling iterations with multiple passes over the data. Matrix sketching techniques give a single-pass $(1+\epsilon)$ approximation for $\ell_{p}$ subspace approximation but require additional passes for subset selection. In this work, we propose an MCMC algorithm to reduce the number of passes required by previous subset selection algorithms based on adaptive sampling. For $p=2$, our algorithm gives subset selection of nearly optimal size in only $2$ passes, whereas the number of passes required in previous work depend on $k$. Our algorithm picks a subset of size $\mathrm{poly}(k/\epsilon)$ that gives $(1+\epsilon)$ approximation to the optimal subspace. The running time of the algorithm is $nd + d~\mathrm{poly}(k/\epsilon)$. We extend our results to the case when outliers are present in the datasets, and suggest a two pass algorithm for the same. Our ideas also extend to give a reduction in the number of passes required by adaptive sampling algorithms for $\ell_{p}$ subspace approximation and subset selection, for $p \geq 2$.
High precision control and deep learning-based corn stand counting algorithms for agricultural robot
Zhang, Zhongzhong, Kayacan, Erkan, Thompson, Benjamin, Chowdhary, Girish
This paper presents high precision control and deep learning-based corn stand counting algorithms for a low-cost, ultra-compact 3D printed and autonomous field robot for agricultural operations. Currently, plant traits, such as emergence rate, biomass, vigor, and stand counting, are measured manually. This is highly labor-intensive and prone to errors. The robot, termed TerraSentia, is designed to automate the measurement of plant traits for efficient phenotyping as an alternative to manual measurements. In this paper, we formulate a Nonlinear Moving Horizon Estimator (NMHE) that identifies key terrain parameters using onboard robot sensors and a learning-based Nonlinear Model Predictive Control (NMPC) that ensures high precision path tracking in the presence of unknown wheel-terrain interaction. Moreover, we develop a machine vision algorithm designed to enable an ultra-compact ground robot to count corn stands by driving through the fields autonomously. The algorithm leverages a deep network to detect corn plants in images, and a visual tracking model to re-identify detected objects at different time steps. We collected data from 53 corn plots in various fields for corn plants around 14 days after emergence (stage V3 - V4). The robot predictions have agreed well with the ground truth with $C_{robot}=1.02 \times C_{human}-0.86$ and a correlation coefficient $R=0.96$. The mean relative error given by the algorithm is $-3.78\%$, and the standard deviation is $6.76\%$. These results indicate a first and significant step towards autonomous robot-based real-time phenotyping using low-cost, ultra-compact ground robots for corn and potentially other crops.
The Effectiveness of Morphology-aware Segmentation in Low-Resource Neural Machine Translation
Sรคlevรค, Jonne, Lignos, Constantine
This paper evaluates the performance of several modern subword segmentation methods in a low-resource neural machine translation setting. We compare segmentations produced by applying BPE at the token or sentence level with morphologically-based segmentations from LMVR and MORSEL. We evaluate translation tasks between English and each of Nepali, Sinhala, and Kazakh, and predict that using morphologically-based segmentation methods would lead to better performance in this setting. However, comparing to BPE, we find that no consistent and reliable differences emerge between the segmentation methods. While morphologically-based methods outperform BPE in a few cases, what performs best tends to vary across tasks, and the performance of segmentation methods is often statistically indistinguishable.
Dependency Graph-to-String Statistical Machine Translation
Li, Liangyou, Way, Andy, Liu, Qun
We present graph-based translation models which translate source graphs into target strings. Source graphs are constructed from dependency trees with extra links so that non-syntactic phrases are connected. Inspired by phrase-based models, we first introduce a translation model which segments a graph into a sequence of disjoint subgraphs and generates a translation by combining subgraph translations left-to-right using beam search. However, similar to phrase-based models, this model is weak at phrase reordering. Therefore, we further introduce a model based on a synchronous node replacement grammar which learns recursive translation rules. We provide two implementations of the model with different restrictions so that source graphs can be parsed efficiently. Experiments on Chinese--English and German--English show that our graph-based models are significantly better than corresponding sequence- and tree-based baselines.
Deep science: AI is in the air, water, soil and steel โ TechCrunch
Research papers come out far too rapidly for anyone to read them all, especially in the field of machine learning, which now affects (and produces papers in) practically every industry and company. This column aims to collect some of the most relevant recent discoveries and papers -- particularly in but not limited to artificial intelligence -- and explain why they matter. This week brings a few unusual applications of or developments in machine learning, as well as a particularly unusual rejection of the method for pandemic-related analysis. One hardly expects to find machine learning in the domain of government regulation, if only because one assumes federal regulators are hopelessly behind the times when it comes to this sort of thing. So it may surprise you that the U.S. Environmental Protection Agency has partnered with researchers at Stanford to algorithmically root out violators of environmental rules.
How can we keep algorithmic racism out of Canadian health care's AI toolkit?
In health care, the promise of artificial intelligence is alluring: With the help of big data sets and algorithms, AI can aid difficult decisions, like triaging patients and determining diagnoses. And since AI leans on statistics rather than human interpretation, the idea is that it's neutral โ it treats everyone in a given data set equally. In October 2019, a study published in the prestigious journal Science showed that a widely used algorithm that predicts which patients will benefit from extra medical care dramatically underestimated the health needs of the sickest Black patients. The algorithm, sold by a health services company called Optum, embodied "significant racial bias," the authors concluded, suggesting that tools used by health systems to manage the care of about 200 million Americans could incorporate similar biases. The problem was fundamental: The commercial algorithm focused on costs, not illness. In looking at which patients would benefit from additional health care services, it underestimated the needs of Black patients because they had cost the system less. But Black patients' costs weren't lower because the patients were healthier; they were lower because they had unequal access to care.
Can artificial intelligence combat wildfires? Sonoma County tests new technology
Sonoma County is adding artificial intelligence to its wildfire-fighting arsenal. The county has entered into an agreement with the South Korean firm Alchera to outfit its network of fire-spotting cameras with software that detects wildfire activity and then alerts authorities. But emergency workers will first have to "teach" the system to differentiate between images that show fire smoke, and others that might show clouds, fog, or vapor from geothermal geysers. The software will use feedback from humans to refine its algorithm and will eventually be able to detect fires on its own -- or at least that's what county officials hope. "It's kind of like learning how to read," Godley said.