top of page
作家相片Edgar Mueller

從入門到入迷:機器學習的基礎概念

已更新:2023年6月10日



機器學習是一種讓機器學習和做事情的技術,就像你們在學習新東西一樣,機器也可以通過學習和經驗來提高它們的表現和效率,機器學習是如何學習的呢?


就像你們在學習寫字一樣,機器也需要先有一些教材或者數據來學習,如果我們想讓機器學習識別狗和貓,我們可以給它們很多照片,讓它們從中學習區分狗和貓,當機器學習了足夠的數據後,它們就可以開始識別狗和貓了。


機器學習的核心原理是訓練模型,模型是一種數學表示,它將輸入數據轉換為輸出數據,模型可以通過訓練來自動學習模式和規律,並將這些模式和規律應用於新數據。


訓練模型的過程涉及到大量的數據,這些數據被稱為訓練數據集,在訓練過程中,模型接收一個輸入,經過處理後產生一個輸出,這個輸出與期望輸出進行比較,並通過反饋機制進行調整,以使模型能夠更好地進行預測,機器學習可以分為監督式學習和非監督式學習,在監督式學習中,模型接收一個輸入和對應的標籤,標籤是對輸入數據的描述,通常是一個類別或數字。在非監督式學習中,模型沒有標籤,它通過尋找數據中的模式來學習。


機器學習還包括深度學習,它是一種基於人工神經網絡的機器學習技術,神經網絡是一種類似於人類大腦的系統,它可以通過層次化的方式自動提取特徵和模式,深度學習已經在圖像識別、自然語言處理和語音識別等領域取得了重大突破。

機器學習是一個涉及多個方向的領域:

  1. 監督學習:監督學習是機器學習的一種常見方法,它是利用有標記的數據集進行訓練的方法,從而讓演算法能夠根據已知的標籤來預測新的標籤,這種方法常見的應用包括圖像識別、語音識別和自然語言處理等。

  2. 非監督學習:非監督學習是一種不需要人工標記數據集的機器學習方法,它是通過對無標記數據的分析和統計建模來找到數據的結構和模式,從而實現聚類、降維、關聯規則挖掘等應用。

  3. 強化學習:強化學習是通過與環境的交互來學習如何做出決策的一種機器學習方法,在強化學習中,智慧體通過試錯的方法來學習與環境的交互,以便最大化回報,強化學習的應用包括遊戲、機器人控制、自動駕駛等領域。

  4. 半監督學習:半監督學習是指同時使用有標記和無標記數據進行訓練的一種機器學習方法,通常使用少量的有標記數據和大量的無標記數據,從而提高模型的準確性和泛化能力。

  5. 深度學習:深度學習是一種利用多層神經網絡進行特徵提取和模式識別的機器學習方法,通常需要大量的標記數據來進行訓練,並且需要使用高性能計算硬體來加速計算,深度學習的應用包括圖像識別、語音識別、自然語言處理等。

  6. 計算機:機器學習也與計算機科學緊密相關,計算機科學為機器學習提供了計算機基礎、演算法設計和最佳化方法,機器學習演算法的設計與實現需要高效的計算機資源。此外,機器學習也被廣泛應用於計算機科學中,例如圖像處理、自然語言處理、計算機安全等領域。

  7. 強化學習 (Reinforcement Learning):是一種機器學習方法,它使用智慧體在環境中進行反覆的試驗和錯誤來學習如何採取行動以最大化某種形式的累積獎勵,強化學習通常用於機器人、遊戲和自然語言處理等領域。

  8. 時序數據分析 (Time Series Analysis):是一種專門處理時序數據的統計方法,可以用於預測、趨勢分析、季節性分析等,時序數據分析在金融、交通、環境監測等領域有著廣泛的應用。

  9. 資料挖掘 (Data Mining):是從大量數據中提取出有用資訊的過程,資料挖掘涵蓋了多種技術和方法,包括聚類、關聯規則、分類等,資料挖掘可以應用於市場營銷、醫學診斷、社交網絡分析等領域。

  10. 圖像處理 (Image Processing):是對圖像進行數學處理和分析的過程,包括圖像增強、分割、標記、識別等,圖像處理在人臉識別、安防監控、自駕車等領域有著廣泛的應用。

機器學習涉及到的方向非常廣泛,從傳統的統計學方法到深度學習,從自然語言處理到圖像處理,都有相應的應用和發展,隨著數據的不斷增長和技術的不斷進步,機器學習將會在更多領域中發揮作用,為人們的生活和工作帶來更多便利和改變。


要理解和應用機器學習,需要具備以下背景知識:

  1. 程式設計:機器學習是基於程式設計實現的,因此需要具備基本的程式設計技能和知識。

  2. 數學基礎:機器學習涉及到很多數學知識,例如線性代數、微積分、機率統計等等,對這些基礎知識的掌握對於理解和應用機器學習非常重要。

  3. 演算法:機器學習是基於演算法實現的,需要瞭解常見的機器學習演算法和其運作原理。

  4. 資料庫與資料處理:機器學習需要大量的資料來進行模型訓練和預測,因此需要瞭解資料庫的基本知識和資料處理的技術。

  5. 電腦硬體:機器學習需要使用高效的運算資源,例如 GPU 和 TPU 等硬體設備,需要瞭解這些硬體設備的基本原理和使用方法。

  6. 領域知識:不同的應用領域需要不同的機器學習模型和演算法,因此需要瞭解相應的領域知識,例如自然語言處理、圖像處理、語音識別等等。


機器學習的應用也非常廣泛,例如你可能在玩遊戲時遇到過電腦玩家,這些電腦玩家就是通過機器學習來學習如何玩遊戲的。機器學習還可以幫助醫生分析病人的病歷,幫助科學家預測氣候變化,甚至可以讓自動駕駛汽車變得更加安全。

當然機器學習並不是完美的技術,也面臨著一些挑戰和問題,如當機器學習的數據不夠全面或者有偏差時,它們可能會出現錯誤的結果,也需要很大的計算資源和能源,這也是需要解決的問題。這些問題並不會影響到機器學習的重要性和價值,隨著科技的發展和機器學習技術的不斷進步,我們相信它們將會繼續對我們的生活和社會產生重大影響。

如果你們對機器學習感興趣,你們可以嘗試一些有趣的玩具和遊戲,例如機器人、智慧手機、智慧家居等等,這些產品背後都是用了機器學習技術,你們也可以學習一些基本的編程知識,來更好地理解機器學習的原理和應用。

以下是一些現實世界中常見的機器學習工具和它們的應用介紹:

  1. TensorFlow:由Google開發的機器學習框架,廣泛應用於影像識別、語音識別、自然語言處理等領域,例如TensorFlow可以用於訓練圖像識別模型,幫助識別圖像中的物體和場景。

  2. Scikit-learn:一個Python庫,用於機器學習和統計分析,包含多種常見的機器學習演算法和工具,如回歸分析、分類、聚類等,例如Scikit-learn可以用於預測房價,分析財務數據,以及分類股票市場。

  3. Keras:一個Python庫,用於深度學習,提供了一個簡單的API,可以用於訓練神經網絡模型,如Keras可以用於訓練圖像識別模型,自然語言處理模型,以及推薦系統模型。

  4. Amazon SageMaker:由亞馬遜開發的機器學習平臺,可用於建立、訓練和部署機器學習模型,例如Amazon SageMaker可以用於訓練預測客戶流失的模型,幫助企業預測客戶流失的可能性和提供相應的策略。

這些工具和應用範例僅是機器學習的冰山一角,機器學習在現實世界中有許多其他的應用和工具,並且在各行各業中都得到了廣泛應用。


現今社會中也有更多產業與面向使用到機器學習:

  1. 醫療保健:機器學習可以幫助醫生和醫療專業人員更快速、準確地診斷疾病,也可以提高治療的效果和預後,例如,機器學習可以分析大量的醫學數據,幫助診斷癌症、心臟病、糖尿病等疾病,還可以幫助醫生預測病人的風險和治療方案。

  2. 金融服務:機器學習可以幫助銀行和金融機構更好地管理風險、預測市場走勢和檢測詐騙行為,例如機器學習可以分析大量的金融市場數據,幫助投資者做出更好的投資決策,同時也可以幫助銀行檢測信用卡詐騙等不良行為。

  3. 社交媒體:機器學習可以幫助社交媒體平臺提高用戶體驗和安全性,例如機器學習可以根據用戶的行為和偏好,推薦更適合的內容和廣告,同時也可以檢測和防止網絡欺淩和惡意行為。

  4. 交通運輸:機器學習可以幫助交通管理部門更好地管理城市交通,提高交通流量和安全性,例如機器學習可以分析交通數據,幫助城市設計更好的交通路線和交通信號系統,同時也可以幫助自動駕駛汽車更好地預測交通情況和避免事故。

這些應用範例展示了機器學習對社會的重要性和貢獻。




最後是以下幾本適合入門機器學習的書籍推薦與線上課程

1.《Python機器學習基礎教程》(Python Machine Learning),作者:Sebastian Raschka,中文版由人民郵電出版社出版,是一本介紹Python機器學習基礎的入門書籍。

2.《深度學習入門:基於Python的理論與實踐》(Deep Learning),作者:Ian Goodfellow、Yoshua Bengio和Aaron Courville,中文版由人民郵電出版社出版,是一本深度學習的入門書籍。

3.《機器學習實戰》(Machine Learning in Action),作者:Peter Harrington,中文版由人民郵電出版社出版,是一本基於Python的機器學習實戰教程。



以下是一些線上的機器學習課程

  1. Coursera:由Stanford大學教授Andrew Ng主講的機器學習課程,是最受歡迎的機器學習入門課程之一。

  2. edX:提供由MIT教授主講的機器學習課程,該課程採用Python和TensorFlow進行實踐。

  3. Udacity:提供免費的機器學習課程,課程覆蓋了機器學習的基礎知識和實踐技能,學習者可以學習並實踐真實世界的問題。



From Beginner to Enthusiast: The Fundamentals of Machine Learning


Machine learning is a fascinating technology that enables machines to learn and perform tasks. Just like you learn new things, machines can also improve their performance and efficiency through learning and experience. So, how does machine learning work?


Just as you learn to write, machines need some learning materials or data to learn. For example, if we want machines to learn to recognize dogs and cats, we can provide them with lots of photos and teach them to differentiate between dogs and cats. Once the machines have learned enough data, they can start recognizing dogs and cats.


The core principle of machine learning is training models. Models are mathematical representations that transform input data into output data. Models can automatically learn patterns and rules through training and apply them to new data.


Training a model involves a large amount of data. This data is called a training dataset. During the training process, the model receives an input, processes it, and produces an output. This output is compared to the expected output, and adjustments are made through feedback mechanisms to improve the model's predictions. Machine learning can be divided into supervised learning and unsupervised learning. In supervised learning, the model receives an input along with corresponding labels. Labels describe the input data and are usually categories or numbers. In unsupervised learning, the model doesn't have labels and learns by finding patterns in the data.


Machine learning also includes deep learning, which is a machine learning technique based on artificial neural networks. Neural networks are systems similar to the human brain that can automatically extract features and patterns through hierarchical processing. Deep learning has made significant breakthroughs in fields such as image recognition, natural language processing, and speech recognition.


Machine learning encompasses various directions:
  • Supervised Learning: Supervised learning is a common method in machine learning. It involves training algorithms using labeled datasets to predict new labels based on known ones. Common applications include image recognition, speech recognition, and natural language processing.

  • Unsupervised Learning: Unsupervised learning is a machine learning method that doesn't require labeled datasets. It finds the structure and patterns in unlabeled data through analysis and statistical modeling. Applications include clustering, dimensionality reduction, and association rule mining.

  • Reinforcement Learning: Reinforcement learning is a machine learning method where an agent learns how to make decisions through interactions with the environment. The agent learns by trial and error to maximize rewards. Applications of reinforcement learning include games, robotics, and autonomous driving.

  • Semi-Supervised Learning: Semi-supervised learning is a machine learning method that uses both labeled and unlabeled data for training. It often utilizes a small amount of labeled data along with a large amount of unlabeled data to improve model accuracy and generalization.

  • Deep Learning: Deep learning is a machine learning method that uses multi-layer neural networks for feature extraction and pattern recognition. It usually requires a large amount of labeled data for training and relies on high-performance computing hardware for accelerated computations. Applications of deep learning include image recognition, speech recognition, and natural language processing.

  • Computer Science: Machine learning is closely related to computer science. Computer science provides the foundations, algorithm design, and optimization methods for machine learning. Efficient computing resources are required for designing and implementing machine learning algorithms. Additionally, machine learning finds extensive applications in computer science, such as image processing, natural language processing, and computer security.


Reinforcement Learning: Reinforcement learning is a machine learning method that learns how to make decisions by repeatedly experimenting and learning from the environment to maximize some form of cumulative reward. Reinforcement learning is commonly used in fields such as robotics, gaming, and natural language processing.


Time Series Analysis: Time series analysis is a statistical method specialized in handling time series data. It can be used for prediction, trend analysis, seasonal analysis, and more. Time series analysis finds extensive applications in finance, transportation, environmental monitoring, and other fields.


Data Mining: Data mining is the process of extracting useful information from large datasets. It involves various techniques and methods, including clustering, association rules, classification, and more. Data mining can be applied in fields such as marketing, medical diagnosis, social network analysis, and more.


Image Processing: Image processing is the mathematical processing and analysis of images, including image enhancement, segmentation, labeling, recognition, and more. Image processing has wide-ranging applications in fields such as facial recognition, security surveillance, self-driving cars, and more.


Machine learning encompasses a wide range of directions, from traditional statistical methods to deep learning, from natural language processing to image processing, each with its own applications and developments. With the continuous growth of data and technological advancements, machine learning will play a significant role in more fields, bringing convenience and transformative changes to people's lives and work.


To understand and apply machine learning, it's essential to have the following background knowledge:
  • Programming: Machine learning is implemented based on programming, so basic programming skills and knowledge are necessary.

  • Mathematical Foundations: Machine learning involves various mathematical concepts, such as linear algebra, calculus, probability, and statistics. Mastering these foundational knowledge is crucial for understanding and applying machine learning.

  • Algorithms: Machine learning is based on algorithms, so it's important to understand common machine learning algorithms and their principles of operation.

  • Databases and Data Processing: Machine learning requires a significant amount of data for model training and prediction, so understanding basic database concepts and data processing techniques is essential.

  • Computer Hardware: Machine learning relies on efficient computing resources, such as GPUs and TPUs. Understanding the basic principles and usage of these hardware devices is necessary.

  • Domain Knowledge: Different application domains require specific machine learning models and algorithms, so understanding the corresponding domain knowledge, such as natural language processing, image processing, speech recognition, etc., is beneficial.

Machine learning finds widespread applications across various industries:
  • Healthcare: Machine learning can assist doctors and healthcare professionals in faster and more accurate diagnoses, improving treatment outcomes and prognosis. For example, machine learning can analyze large medical datasets to help diagnose diseases such as cancer, heart diseases, diabetes, and predict patient risks and treatment strategies.

  • Financial Services: Machine learning can help banks and financial institutions better manage risks, predict market trends, and detect fraudulent activities. For instance, machine learning can analyze vast financial market data to aid investors in making better investment decisions and help banks detect credit card fraud and other malpractices.

  • Social Media: Machine learning can enhance user experience and security on social media platforms. For example, machine learning can recommend more suitable content and advertisements based on user behavior and preferences, as well as detect and prevent online bullying and malicious activities.

  • Transportation: Machine learning can assist transportation authorities in managing city traffic, improving traffic flow, and safety. For instance, machine learning can analyze traffic data to help design better transportation routes and signal systems for cities and aid autonomous vehicles in predicting traffic conditions and avoiding accidents.

These applications demonstrate the importance and contributions of machine learning to society.


Lastly, here are a few recommended books and online courses for getting started with machine learning:


Books:

  1. "Python Machine Learning" by Sebastian Raschka: This book provides an introduction to the basics of machine learning using Python.

  2. "Deep Learning" by Ian Goodfellow, Yoshua Bengio, and Aaron Courville: This book is an introduction to deep learning theory and practice, using Python.

  3. "Machine Learning in Action" by Peter Harrington: This book is a practical guide to machine learning with Python.

Online Courses:

  • Coursera: This platform offers a machine learning course taught by Professor Andrew Ng from Stanford University. It is one of the most popular introductory machine learning courses.

  • edX: This platform provides a machine learning course taught by professors from MIT. The course utilizes Python and TensorFlow for practical implementations.

  • Udacity: Udacity offers free machine learning courses covering foundational knowledge and practical skills. Learners can study and practice real-world problem-solving.

Remember, if you're interested in machine learning, you can try out some fun toys and games, such as robots, smartphones, and smart homes. These products incorporate machine learning technology. Additionally, learning some basic programming knowledge will help you better understand the principles and applications of machine learning.




bottom of page