Data Science Theory Crash Course

Master the core theory behind neural networks, machine learning algorithms, classifiers and more of the crucial topics you need before building projects.

The Best Data Science Theory Guide

Do you need to learn data science and algorithms?

Do you need an introduction to data science with only the core concepts, formula and topics you need to know before jumping into projects?

This is the course for you.

Enroll now to learn the core theory you need to understand before applying that theory directly into your code in beginner data science projects.

Don't wait! Enroll while spots are open.


Java Data Science

Part 1: K-Nearest Neighbors Theory
  • What is the K-NN algorithm?
  • What can the K-NN algorithm used for?
  • How does the K-NN algorithm work? (What does the K stand for?)
  • Why does K-NN matter?
  • What are the pros and cons?
  • What equations do we need to know to build the K-NN algorithm?
  • What is Euclidean distance?
  • What is normalizing?
  • What is a ‘vote’ in K-NN?

Part 2: Decision Trees Theory

  • What are decision trees?
  • What is ‘best feature to split on’?
  • What is Information Gain?
  • How is Information Gain used in decision trees?
  • What is entropy?

Part 3: Neural Networks Theory

  • What are neural networks?
  • What are the parts to a neural network?
  • What are neural networks used for?
  • What projects can we build?
  • What is a ‘weight’?
  • What do ‘target result’ and ‘error’ mean in neural networks?
  • What is an activation function?
  • What is a step function?
  • What is an epoch?
  • What is learning rate?
  • What is a linear classifier?
  • What is a binary classifier?
  • What is supervised learning vs unsupervised learning?
  • What is the perceptron algorithm?

Part 4: Data Classification and Naive Bayes Theory

  • What is Sentiment Classification?
  • What is Bayes Theorem?
  • What is Naive Bayes?
  • What are the types of Naive Bayes classifiers?
  • What does the ‘Naive’ mean?
  • What is the Bag of Words model?
  • What is data smoothing?
  • What is prior probability distribution?
  • How do you avoid underflow errors?
  • And more!

Your Instructor

Alexandra Kropf
Alexandra Kropf

Alexandra Kropf is Mammoth Interactive's CLO and a software developer with extensive experience in full-stack web development, app development and game development. She has helped produce courses for Mammoth Interactive since 2016, including the Coding Interview series in Java, JavaScript, C++, C#, Python and Swift.

Mammoth Interactive is a leading online course provider in everything from learning to code to becoming a YouTube star. Mammoth Interactive courses have been featured on Harvard’s edX, Business Insider and more.

Over 12 years, Mammoth Interactive has built a global student community with 4 million courses sold. Mammoth Interactive has released over 350 courses and 3,500 hours of video content.

Founder and CEO John Bura has been programming since 1997 and teaching since 2002. John has created top-selling applications for iOS, Xbox and more. John also runs SaaS company Devonian Apps, building efficiency-minded software for technology workers like you.



  • Lifetime access that never expires
  • Project-based curriculum to superboost your portfolio
  • Graduation certificate for every course
  • Absolute beginner-friendly
  • New courses every month
  • Efficient lectures with step by step explanations
  • Relevant industry topics 8 years of award-winning course delivery
  • 700,000 students in 186 countries
  • Learn with free tools and affordable courses


  • No experience necessary.
  • Experience in statistics and math is helpful but not required.

Frequently Asked Questions

When does the course start and finish?
The course starts now and never ends! It is a completely self-paced online course - you decide when you start and when you finish.
How long do I have access to the course?
How does lifetime access sound? After enrolling, you have unlimited access to this course for as long as you like - across any and all devices you own.
What if I am unhappy with the course?
We would never want you to be unhappy! If you are unsatisfied with your purchase, contact us in the first 30 days and we will give you a full refund.
What is the format of the courses?
Average courses are 5-50 hours long, with our biggest (to date) being Hello Coding 2.0, at 250 hours of content! Most lessons are between 15 and 30 minutes long, and they’re all available online that you can watch at any time that’s convenient for you. The videos feature a live recording of your instructor's screen as they develop in realtime. With all source code and reference files included. So there will be absolutely no guesswork for you. And in case you ever get stuck, you can ask any questions and leave comments under each lecture.
Do I get course certificates?
Yes, a course certificate will be generated at the end of each course you complete! Along with projects, certificates are a way you can prove your work on LinkedIn.
How much time do I need in order to take each course?
You can spend as much or as little time as you want. If you enroll in Lifetime Access, you get lifetime access to all course materials. With Lifetime Access, there is no expiry. You aren't required to complete the course within a certain time period. You can follow the course at your own pace and always come back to the videos later when you want to revisit the material or work on improving certain skills.
Do I have to show up at a particular place or a particular time?
No, each course happens online, and you can take it from any place where you have an internet connection. You can view all lectures offline via the Teachable iOS app. All lectures are prerecorded so you can watch them at any time that works for you. Of course, you can also enjoy all the lectures on your phone and tablet.
What if I’m not good with technology?
The majority of Mammoth Interactive students are complete beginners. Even if you feel like you know nothing about technology, you won’t feel left out. All technical concepts are described in simple terms while avoiding unnecessary jargon. Each course starts from scratch and builds up your knowledge substantially in steps. Students from age 5 to 70 have successfully completed our courses. And just in case you get stuck, you can always ask any questions under each lecture, which will be promptly answered by one of my team members.
What if I'm an experienced developer?
Stack Overflow's yearly developer survey found that developers over age 50 start to make less than their younger counterparts. Don't become one of the people affected by skill stagnation. Enroll in our school to future-proof your career for life. If you're an experienced developer, you will still benefit from Mammoth Interactive courses. By starting from scratch with each course, you will revisit the fundamentals and undo bad coding habits. You'll also find it easier to pick up new languages, making you able to take more courses and broaden your skillset.

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