Introduction to Machine Learning
Tags: aws, machinelearning, beginners, deeplearning
Published: 2023-06-28 05:55:50

Machine learning is revolutionizing society by improving autonomous vehicles, language translation, and AI assistants. It can make work safer and speed up the process of discovering new drugs. Machine learning uses models trained to find patterns and make predictions based on data. It is a type of artificial intelligence that helps computers learn and get better through experience. There are three different approaches within machine learning: supervised learning, unsupervised learning, and reinforcement learning.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/wchkggvlaaxq3sw1nfiz.png)


- **Supervised learning** involves assigning a label or output value to each training sample in the dataset. The algorithm learns to predict labels or output values. Supervised learning means using labelled data to train algorithms and make predictions. For example, predicting house prices or classifying objects in images. An example of supervised learning is when the number of snow cones sold is predicted based on the average temperature outside. 

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/a2t3kfpaqpe5oiwjaxk5.png)

- **Unsupervised learning** doesn't have labels for the training data. A machine learning algorithm attempts to understand the patterns or distributions that control the data. Unsupervised learning involves exploring patterns and distributions in unlabeled data to gain insights and understand underlying structures.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/0rda2i1q7naqp5u1xoqp.png)


- **Reinforcement learning** is a process where an algorithm determines the best actions to take in a given situation to achieve a specific goal and get a reward in the form of a number. This approach is different from supervised and unsupervised learning. Reinforcement learning is like teaching a pet, where good actions are rewarded and bad actions are punished to achieve the best results.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/r7l5utquvmgksr4ll7om.png)


## Components of machine learning
Machine learning has three main components: **a machine learning model**, **a model training algorithm**, and **a model inference algorithm**. The model is flexible and can be changed to fit different needs, like molding clay into different shapes. The training algorithm changes the model parameters to meet the goals, while model inference means the model that has been trained and is used to make predictions.

## Two Sided Examples
**_Example 1:_**
Suppose you are the owner of a snow cone cart and you possess some data regarding the average daily sales of snow cones, which is based on the high temperature. To ensure that you have sufficient inventory on hand during peak sales days, you aim to gain a deeper understanding of this relationship.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/hggwl7jxxyb2rb7uhljr.png)

The graph above displays an instance of a model, specifically a linear regression model (represented by the solid line). Based on the given data, it is evident that the model predicts a direct correlation between the high temperature for the day and the average number of snow cones sold. Sweet!

_**Example 2:**_
Here's another example that uses the same linear regression model, but with different data and a different question to answer.
You work in higher education and want to know how the cost of enrollment affects the number of students attending college. Our model predicts that if tuition costs increase, fewer people will attend college.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/sn29mk7dhfrf621qin4y.png)

When we use the same linear regression model (shown as the solid line), we can observe that as the cost increases, the number of people attending college decreases.
Both examples show that a model is a programme that can be customised by the data used to train it.

The machine learning process involves several steps, including defining the problem, creating a dataset, training the model, evaluating the model, and finally using the model. Clustering is a type of learning that doesn't require supervision and helps identify natural groups in the data.

Creating a dataset is an important part of the machine learning process, which includes gathering data, examining it, calculating basic statistics, and data visualization. Data preparation is crucial for creating a successful machine learning solution. Data preparation involves collecting important information, checking data integrity, and using summary statistics and data visualization to understand trends and patterns.To understand your data better in machine learning, you use various statistical tools. The sklearn library provides numerous examples and tutorials.This is a guide on how to detect outliers in a real data set using [scikit-learn version 1.2.2 documentation](https://scikit-learn.org/stable/auto_examples/applications/plot_outlier_detection_wine.html#sphx-glr-auto-examples-applications-plot-outlier-detection-wine-py).

Model selection is a crucial step in evaluating the performance of a model. Loss functions are used to calculate the difference between predicted values and actual values it is trying to predict. Model selection involves selecting the most appropriate model for a given problem, and hyperparameters refer to the specific settings that have an impact on the training process.

Evaluating a machine learning model involves measuring its performance using statistical metrics such as accuracy. This process involves making changes to parameters, selecting models, adjusting data, or looking at the problem from a different perspective. After training, a model that meets the requirements is found, and the completed model can be used for its intended purpose.

**Log loss** measures the uncertainty a model has when predicting outcomes, indicating how much the model trusts its predictions. Machine learning is a growing field that combines statistics, applied math, and computer science, with its main components being clustering, training, evaluating, and using the model. Log loss measures the uncertainty of a machine learning model in predicting outcomes, indicating its confidence in its predictions. It is crucial to continuously check the model's accuracy and adjust its predictions as needed.

Machine learning can be used to predict house prices, study book trends, and predict potential spills in industrial chemical plants. Data preprocessing involves making text easier to analyze, while bag-of-words is a tool for identifying important information from written words. Data vectorization converts non-numeric data into numerical format, and the k-means clustering model is used to group books into clusters. Silhouette coefficients, which range from -1 to 1, describe clusters found during modeling.

A company aims to improve response time to spills by using the plant's surveillance system to detect spills. To detect spills, supervised machine learning classification is used to predict if an image shows a spill or not. **Convolutional Neural Network (CNN)** is a deep learning model commonly used for image processing tasks.

Accuracy is important for measuring performance, but precision and recall are more important when dealing with spill predictions. To evaluate the model's performance in real-life spill situations, the model is compared to past spills recorded by the surveillance system. If there are problems, the janitorial team receives a message.

In summary, machine learning plays a crucial role in various applications, including predicting house prices, studying book trends, and detecting potential spills in industrial chemical plants. While accuracy is important for measuring performance, precision and recall are more important in real-life spill situations.


The [scikit-learn library in Python](https://scikit-learn.org/stable/) has tools that can help you implement the model training algorithm.