A while ago, I wrote two blogposts about image classification with Keras and about how to use your own models or pretrained models for predictions and using LIME to explain to predictions. Recently, I came across this blogpost on using Keras to extract learned features from models and use those to cluster images. It is written in Python, though - so I adapted the code to R. You find the results below.

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After posting my short blog post about Text-to-speech with R, I got two very useful tips. One was to use the googleLanguageR package, which uses the Google Cloud Text-to-Speech API. And indeed, it was very easy to use and the resulting audio sounded much better than what I tried before! Here’s a short example of how to use the package for TTS: Set up Google Cloud and authentification You first need to set up a Google Cloud Account and provide credit card information (the first year is free to use, though).

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These are the slides from my workshop: Introduction to Machine Learning with R which I gave at the University of Heidelberg, Germany on June 28th 2018. The entire code accompanying the workshop can be found below the video. The workshop covered the basics of machine learning. With an example dataset I went through a standard machine learning workflow in R with the packages caret and h2o: reading in data exploratory data analysis missingness feature engineering training and test split model training with Random Forests, Gradient Boosting, Neural Nets, etc.

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Computers started talking to us! They do this with so called Text-to-Speech (TTS) systems. With neural nets, deep learning and lots of training data, these systems have gotten a whole lot better in recent years. In some cases, they are so good that you can’t distinguish between human and machine voice. In one of our recent codecentric.AI videos, we compared different Text-to-Speech systems (the video is in German, though - but the text snippets and their voice recordings we show in the video are a mix of German and English).

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Last week I published a blog post about how easy it is to train image classification models with Keras. What I did not show in that post was how to use the model for making predictions. This, I will do here. But predictions alone are boring, so I’m adding explanations for the predictions using the lime package. I have already written a few blog posts (here, here and here) about LIME and have given talks (here and here) about it, too.

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I’ve been using keras and TensorFlow for a while now - and love its simplicity and straight-forward way to modeling. As part of the latest update to my Workshop about deep learning with R and keras I’ve added a new example analysis: Building an image classifier to differentiate different types of fruits And I was (again) suprised how fast and easy it was to build the model; it took not even half an hour and only around 100 lines of code (counting only the main code; for this post I added comments and line breaks to make it easier to read)!

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On May 21st and 22nd, I had the honor of having been chosen to attend the rOpenSci unconference 2018 in Seattle. It was a great event and I got to meet many amazing people! rOpenSci rOpenSci is a non-profit organisation that maintains a number of widely used R packages and is very active in promoting a community spirit around the R-world. Their core values are to have open and reproducible research, shared data and easy-to-use tools and to make all this accessible to a large number of people.

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