python – Data Science Portfolio

February 8, 2022 Recommender Systems

Using Scikit-Surprise to Create a Simple Recipe Collaborative Filtering Recommender System.

Companies all over the world are increasingly utilizing recommender systems. These algorithms can be used by online stores, streaming services, or social networks to recommend items to users based on their previous behavior (either consumed items or searched items). There are several approaches to developing recommendation systems. We can build a recommender system based on the content of the item so that the system recommends similar items to the ones the user usually likes (Content-Based recommender

October 7, 2021 Time Series

Forecasting Time Series with Auto-Arima

In this article, I attempt to compare the results of the auto arima function with the ARIMA model we developed in the article Forecasting Time Series with ARIMA (https://www.alldatascience.com/time-series/forecasting-time-series-with-arima/). I made this attempt to see how it works and what the differences are.The parameters selected by auto-arima are slightly different than the ones selected by me in the other article.Auto arima has the advantage of attempting to find the best ARIMA parameters by comparing the

September 14, 2021 Time Series

Forecasting time series with ARIMA

In this post, I’ll attempt to show how to forecast time series data using ARIMA (autoregressive integrated moving average). As usual, I try to practice with “real-world”, which can be obtained easily by downloading open data from government websites. I chose the unemployment rate in the European Union’s 27 member countries. The data were obtained from the OECD data portal (http://dataportal.oecd.org/). First of all, I’m going to try to clean up the data, in this

August 9, 2021 Classification

Comparing Data Augmentation Techniques to Deal with an Unbalanced Dataset (Pollution Levels Predictions)

Predicting NO2 levels in Madrid While looking for data to develop my data science skills, I came up with the idea of searching open data portals. I wanted to look at actual datasets and find out what they were like. For this purpose, I chose open data from the Madrid Open Data Portal (https://datos.madrid.es/portal/site/egob). I will try to predict NO2 concentration using weather and traffic data. This is not meant to be a definitive prediction

February 14, 2021 NLP

NLP: Opinion classification

Let’s perform some classification methods on the same tripadvisor data as in the post https://www.alldatascience.com/nlp/nlp-target-and-aspect-detection-with-python. In this case we are going to read and preprocess the data again, then we are going to vectorize it in different ways, 1. With TF-IDF vectorizer that creates vectors having into account the frequency of words in a document and the frequency of words in all documents, decreasing weight of the words that appear too often (they can bee

February 5, 2021 NLP

NLP: Target and aspect detection with Python.

In this post we perform target and aspect detection on a dataset about tripadvisor opinions. Target or topic are the words or topics the opinions are about. Aspects are parts or features of the target. Here we explore the target detection using word embeddings (Word2Vec) which extracts similar words by context and try to extract aspects of the target by searching close words wusing the WordNet synsets. First, we perform data preprocessing by removing stopwords

January 22, 2021 Classification

Wine dataset analysis with Python

In this post we explore the wine dataset. First, we perform descriptive and exploratory data analysis. Next, we run dimensionality reduction with PCA and TSNE algorithms in order to check their functionality. Finally a random forest classifier is implemented, comparing different parameter values in order to check how the impact on the classifier results.