deep data-driven astronomyrvanderb/kes/sedaghat/dl_eso.pdfneural network... nima sedaghat, sep....

Nima Sedaghat, Sep. 2019, ESO, Garching

Deep Data-driven Astronomy

Nima Sedaghat


Outline

● Basic Ideas behind Machine Learning● Classical Machine Learning vs. Deep Learning● Rapid Evolution of Deep Learning

→ Encoder-Decoder Architectures

● TransiNet

● Letting Spectra Speak for Themselves


Machine Learning


30 second intro to machine learning



DOG? DOG?

DOG?

CAT?

CAT?CAT?

Guess



DOG? DOG?

DOG?

CAT?

CAT?CAT?

Update



DOG? DOG?

CAT?

CAT?

DOG?DOG?

EducatedGuess



Update

DOG? DOG?

CAT?

CAT?

DOG?DOG?



CAT? DOG?

CAT?

CAT?

DOG?CAT?

EducatedGuess


Real-world Example

Human or not?

www.istockphoto.com


“Feature”


if (there is a circle somewhere close to the top)

if (there are two parallel vertical lines below it)

if ...Probably a human!

else

if ...Probably a human without a neck!

else

not a human

Featrues → Final Answers(inference)


From If-else to Learning by Examples


From If-else to Learning by Examples

“Model”


Model

Human?Not Human?


Different Methods – Same Idea

Support Vector Machine

DecisionTree

NeuralNetwork

...


Classical Machine Learning vs.

Deep Learning


From Hand-Crafted Features to Representation Learning

Alex, D., 2017


Why didn’t we do it before?

We needed to go deeper: more parameters, more sophisticated features

It would take forever to tell a cat from a dog!


What made it possible?

Convolutional Layers


GPU: Graphical Processing Unit

https://www.wikihow.com/Connect-an-External-TV-Tuner-Card-to-a-Desktop


GPU: Graphical Processing Unit


Convolutional Layers

https://www.analyticsindiamag.com/convolutional-neural-network-image-classification-overview


Why Convolutional Layers help?

“Shared Weights”

Seongwon Hwang, “Convolutional Neural Network (CNN) presentation from theory to code in Theano”


Deep ConvNets


Hierarchical Representation Learning


On the Importance of Data


On the Importance of Data

over-fittingSmall Dataset

It’s a cat


The Rapid Evolution of Deep Learning


Classification

CAT? DOG?

CAT?

CAT?

DOG?CAT?

EducatedGuess


Classification

https://github.com/EdwardJKim/dl4astro/


Regression

Sedaghat, Brox, “Unsupervised Generation of a Viewpoint Annotated Car Dataset from Videos”


● Question: What examples can you think of in Astronomy?

Regression


Encoder-Decoder Networks


E.g. Auto-Encoder


Why an Auto-Encoder?

Code


E.g. De-noising

Question: How would you train this?


E.g. Segmentation


E.g. Optical Flow (Motion) Estimation


Application Example: TransiNet

Reference Image Science Image Ideal output

Nima Sedaghat, Ashish Mahabalhttps://doi.org/10.1093/mnras/sty613

Watch presentation @ Astroinformatics '18

https://youtu.be/mve5N5fPpsY?list=PLPXTfPKnWAgPuv7m0rMr7yttHg-JrEHaH

https://academic.oup.com/mnras/article/476/4/5365/4968015


Application Example

Letting Spectra Speak for themselves!


The Idea


First Results


Retrieval

Query Spectrum


Retrieval

Search Results:


Serendipitous Finding

● Does the network know something we don’t?

deep data-driven astronomyrvanderb/kes/sedaghat/dl_eso.pdfneural network... nima sedaghat, sep....

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