Course 4 of 7 · 30 lessons · Free
Data Science with Python
Python basics, statistics, machine learning, NLP and deep learning, with code you run in the browser.
Comes after: SQL for Data Analysis
Python Basics
- Python Variables and Data TypesStore values in variables and meet the four basic types: int, float, str and bool.
- Python Lists and LoopsKeep many values in a list, then process them with for loops and list comprehensions.
- Python DictionariesStore data as key-value pairs: the structure behind JSON, records and model settings.
- Python FunctionsPackage code into reusable functions with parameters, default values and return values.
- NumPy ArraysDo fast maths on whole arrays at once with NumPy, the foundation of the Python data stack.
- pandas DataFramesLoad, filter, group and summarise tabular data with pandas.
- Data Visualization with MatplotlibTurn a DataFrame into line, bar, scatter and histogram charts, and learn what each is for.
Statistics
- Descriptive StatisticsSummarise a dataset with measures of centre and spread, find outliers and read a five-number summary.
- Probability and DistributionsLearn the rules of probability and the two distributions you will meet most: the normal and the binomial.
- Sampling and Confidence IntervalsSee why averages of samples behave predictably and how to state an estimate together with its uncertainty.
- Hypothesis TestingDecide whether a difference in your data is real or could be chance, using p-values, t-tests and chi-square tests.
- Correlation and Simple Linear RegressionMeasure how strongly two variables move together and fit a straight line to predict one from the other.
Machine Learning
- The Machine Learning WorkflowTrain your first model with scikit-learn and learn the steps every project follows, from features to test score.
- Linear RegressionPredict a number from several features, read the coefficients and measure the error with MAE, RMSE and R squared.
- Classification with Logistic RegressionPredict a category and its probability, scale the features and choose a decision threshold.
- Evaluating Models: Precision, Recall and Cross-ValidationGo beyond accuracy with the confusion matrix, precision, recall, F1 and ROC AUC, and get a reliable score with cross-validation.
- Decision Trees and Random ForestsLearn the models that power most tabular machine learning, see a tree overfit and fix it with a forest.
- Feature Engineering and PipelinesHandle missing values, encode categories and scale numbers inside a pipeline that prevents data leakage.
- Overfitting, Underfitting and Hyperparameter TuningDiagnose a model that is too simple or too complex and find better settings with grid search.
- Unsupervised Learning: Clustering and PCAFind groups in unlabelled data with k-means and reduce many features to a few with principal component analysis.
Natural Language Processing
- Text PreprocessingTurn raw text into clean tokens a program can count: lowercase, tokenise, remove stop words and normalise.
- Bag of Words and TF-IDFConvert documents into numeric vectors a model can use, and measure how similar two texts are.
- Text ClassificationTrain a model that labels text, such as positive or negative reviews, and see which words drive its decisions.
- Word EmbeddingsRepresent words as vectors that capture meaning, so that similar words are close together.
- Transformers for NLPUnderstand attention, the mechanism behind modern language models, and use a pretrained model in a few lines.
Deep Learning
- Neural Network BasicsBuild a neuron, an activation function and a layer in NumPy, and see how data flows through a network.
- Training Neural NetworksLearn how a network improves: loss functions, gradient descent and backpropagation, with a network trained from scratch.
- PyTorch BasicsWrite a real training loop with tensors, automatic gradients and a model class, the way deep learning is done in practice.
- Convolutional Neural NetworksSee how networks recognise images: filters that detect edges, pooling that shrinks the picture, and layers that build up to objects.
- Sequence Models and the Road to TransformersFollow the path from recurrent networks to attention, and see how deep learning leads into generative AI.