In this Kaggle competition set of 5,863 chest X-ray images (anterior-posterior) were selected from retrospective cohorts of paediatric patients, between the age of one to five years old, in Guangzhou. All chest X-ray imaging was performed as part of the patient’s routine clinical care.
All chest radiographs were screened by two expert physicians for quality control and removing all low quality or unreadable scans.
In the picture below are show the three type of chest X-ray present in the database:
On the left-hand side it is present an image of a healthy individual with clear lungs and no areas of abnormal opacification. In the middle and right-hand side images are present a patient affected by bacterial and viral pneumonia respectively. The latter, presents a more diffuse ‘‘interstitial’’ pattern in both lungs. while the first typically exhibits a focal lobar consolidation, in this case in the right upper lobe (white arrows).
For this particular challenge we are requested to discern only healthy vs pneumonia affected chest X-ray.
Probability calibration is the process of calibrating an ML model to return the true likelihood of an event. This is necessary when we need the probability of the event in question rather than its classification.
Image that you have two models to predict rainy days, Model A and Model B. Both models have an accuracy of 0.8. And indeed, for every 10 rainy days, both mislabelled two days. But if we look at the probability connected to each prediction, we can see that Model A reports a probability of 80%, while Model B of 100%.
This means that model B is 100% sure that it will rain, even when it will not, while model A is only 80% sure. It appears that model B is overconfident with its prediction, while model A is more cautious.
And it’s this level of confidence in predictions that makes Model A a more reliable model with respect to Model B; Model A is better despite the two models having the same accuracy.
Model B offers a more yes-or-no prediction, while Model A tells us the true likelihood of the event. And in real life, when we look at the weather forecast, we get the prediction and its probability, leaving us to decide if, for example, a 30% risk of rain is acceptable or not.
You know when you have coded your biggest project and every time it runs you can barely figure out what is doing, only by reading a series of print statements and the creation of strategically saved files?
Well if that is the case, you ought to learn logging and step up your game.
With a proper system of logging. you will have a consistent, ordered and a more reliable way to understand your own code, to time and track its progression and capture bugs easily.
Let’s break down the advantages of logging:
Formatting: Logging allows you to standardize every message using a format of your choosing.
Time tracking: Alongside the message you can add the time when it is generated.
Compact: All messages are gathered in files, you don’t need to scroll up continuously.
Versatility: Print does not work everywhere (i.e., objects without __str__ methods).
Flexibility: Logging allows different levels of importance to your messages so you regulate what to show.
With all of this, you won’t be the only one who can understand your code.
If you have been more than five seconds on r/dataisbeautiful/, you will have probably encountered a Sankey plot. Everyone uses to track their expenses, job searching and every multi step processes. Indeed, it is very suitable to visualize the progression of events and their outcome. And in my opinion, they look great!
Therefore, let’s see how to do in Python: Jupyter Notebook here
How to create a simple weather forecast model using ML and how to find public available weather data with ERA5!
As a data scientist at Intellegens, I work on a plethora of different projects for different industries including materials, drug design, and chemicals. For one particular project looking I was in desperate need of weather data. I needed things like, temperature, humidity, rainfall, etc. Given the spacetime coordinates (date, time and GPS location). And this made me fall into a rabbit hole so deep, that I decided to share it with you!
I thought that finding an API that could give this type of information was going to be easy. I didn’t foresee weather data to be one of the most jealously kept types of data.
If you search for “free weather API”, you will see plenty of similar websites with different services but not actually free and even if there is a free package, it will never have historical weather records.You really need to search hard before finding the Climate Data Store (CDS) web site.
Let’s see a simple way to produce compute a linear regression using Python.
import matplotlib.pyplot as plt # To plot the graph
# Import a database to use in this case I choose the famous Iris database
import matplotlib.pyplot as plt
import pandas as pd
iris = pd.DataFrame(db.load_iris()['data'],
Let’s take two columns from the database and plot it: