Friday, July 21, 2017

DUOLINGO: Providing free, global, language education - 150 million learners

·         Duolingo is a freemium language-learning platform that includes a language learning website and app, as well as a digital language proficiency assessment exam. (A freemium is a pricing strategy by which a product or service is provided free of charge, but money (premium) is charged for advanced features, functionality, or related products and services2);
·         Duolingo offers all its language courses free of charge;
·         The language-learning website and app offers 68 different language courses across 23 languages – with 22 additional courses in development (as of Nov 2016);
·         The app is available on iOS, Android and Windows 8 and 10 platforms with about 150 million registered learners/users across the world.

·         The Duolingo project was started at the end of 2009 in Pittsburgh, U.S., by Carnegie Mellon University professor Luis von Ahn and his graduate student, Severin Hacker;
·         One important inspiration for Duolingo came from von Ahn himself.  He was born in Guatemala and saw how expensive it was for people in his community to learn English;
·         Both co-founders believe that “free education will really change the world” and wanted to supply the people an outlet to do so – hence the initiation of Duolingo.

·         Duolingo is a great way to learn a language. It provides personalized education as people learn in different ways;
·         It’s addictive – split into bite-sized units that feel like games – gamification poured into every lesson;
·         Learners can study during breaks, commute, while waiting in line;
·         Duolingo teaches learners to read, write, listen, and speak a language;
·         Extremely effective;
·         Completely free so it is universally accessible: no annoying ads, no misleading In-App purchases, no subscription fees;
·         They know it’s hard to stay motivated when learning online, so they made Duolingo so fun that people would prefer picking up new skills over playing a game.

·         According to Dave (studying French from the English platform):
o   Duolingo is “so much better, not to mention free” – compared to the ones he tried before;
o   Duolingo is “a lot more interactive and much smarter at becoming progressively yet appropriately more difficult as you learn things;”
·          According to Mary (studying German from the English platform):
o   “Duolingo makes learning German language fun and I look forward to my next 10 minutes a day.”
·         I opened and did the Basic French lessons from English platform, and saw that:
o   Daily goal options for the lessons are “only” 5, 10, 15 and 20 minutes/day.  These "short" lesson durations look very doable and encouraging.  The fact that learners do these "short" lessons daily will ensure that they will build up substantial expertise over time;
o   The lesson activities are “fun” and “interesting.”


High Valyrian*

*Created language 

·         Create a profile to save your progress;
·         To start on a Duolingo lesson, please click here.


Posted by: Dr. Nat Tuivavalagi

Wednesday, July 12, 2017

Deep Learning – Moving Machines Closer to Attaining Artificial Intelligence

·         In recent years, Deep Learning has become an area of active research, and has also become a buzzword that has been tossed around a lot;
·         Deep Learning is becoming increasingly important these days because it teaches computers the skills our brains do naturally e.g. recognizing handwritten digits;
·         This posting is focused primarily to those with little or no understanding of Deep Learning.  The main goal is to increase understanding of this topic through simple language, and to point out some free online courses and resources that are available for a better understanding of Deep Learning.

·         “Deep Learning” comes under the broader field of “Machine Learning” which was covered in the previous post; 
·         Deep Learning is a specific type of Machine Learning, focusing on high order statistics1;
·         Deep Learning is a new area of Machine Learning research. It was introduced with the objective of moving Machine Learning closer to one of its original goals, Artificial Intelligence2;
·         Please consider having another quick look at the previous post on Machine Learning (July 1, 2017 – see below).

WHAT IS DEEP LEARNING?  We hope to arrive at some understanding of Deep Learning by considering how this activity has been described in various publications:
·         Deep Learning has been described as follows3:
o   Deep Learning is a paradigm (example/ pattern/ model) for performing Machine Learning;
o  Deep Learning is a form of Machine Learning that uses a model that’s very much inspired by the structure of the brain's computing.  (Hence we call this model a neural network); and
o   Deep Learning is an extremely powerful tool for modern Machine Learning;
·         Deep Learning is a branch of Machine Learning that uses algorithms* to do things like recognizing objects and understanding human speech4. [*Algorithms = Processes or set of rules to be followed in solving problems];
·         Deep Learning refers to  learning tasks of artificial neural networks (ANNs) that contain more than one hidden layer. (Deep learning is part of a broader family of Machine Learning methods based on learning data representations, as opposed to task specific algorithms)5;
·        In Deep Learning, a software attempts to mimic the brain activity in layers of neurons in the neocortex, (the wrinkly 80 percent of the brain where thinking occurs).  The software learns in a very real sense, to recognize patterns in digital representations of sounds, images, and other data6. [In the human brain, the neocortex has six layers and contains between 10 and 14 billion neurons];
·         Deep Learning employs numerous, similar, yet distinct, deep neural network architectures to solve various problems in natural language processing, computer vision, bioinformatics, and many other fields7.

·         The prerequisites for understanding and applying Deep Learning are8:
o   Linear algebra;
o   Calculus;
o   Statistics;
o   Programming; and
o   Some Machine Learning.

·         Deep Learning is responsible for recent advances in4:
o   Speech recognition;
o   Computer vision;
o   Natural language processing; and
o   Audio recognition.
·         Apart from speech recognition, Deep Learning methods have dramatically improved the state-of-the-art in9:
o   Visual object recognition;
o   Object detection;
o   Drug discovery;
o   Genomics; and
o   Many other domains.
·         Some inspirational examples of Deep Learning include10:
o   Colorization of Black and White Images;
o   Adding Sounds to Silent Movies;
o   Automatic Machine Translation;
o   Object Classification in Photographs;
o   Automatic Handwriting Generation;
o   Image Caption Generation; and
o   Automatic Game Playing.

·         For free online courses and resources relating to Deep Learning, please click here.


Posted by Dr. Nat Tuivavalagi

Saturday, July 1, 2017

Machine Learning – One of the most popular MOOCs of all time with over one million enrollments

“Machine Learning,”  has been reported1 as one of the most popular MOOCs of all time. A program from Stanford University on Coursera, with a total enrollment of 1,122,031.  With such a high interest in “Machine Learning,” one wonders: 1) What is Machine Learning? 2) How does Machine Learning help us in our daily life? 3) Why should we study Machine Learning? 4) How do we get started studying Machine Learning? 5) What's out there for  Machine Learning MOOCs and Other MOOCs?

First we need to describe an “algorithm” –  defined2 as a procedure for solving a problem based on conducting a sequence of specified actions. 

In Machine Learning (ML)3, an ML algorithm is given a “teaching set” of data, then asked to use that data to answer a question.  For example, you might provide a computer a “teaching set” of photographs some of which say “this is a cat” and some of which say, “this is not a cat.”  Then you could show the computer a series of new photos and the computer would identify which photos were of cats.

Every photo identified by the computer gets added to the “teaching set,” and the program effectively gets “smarter” and more efficient at completing its task over time.

Machine Learning has helped us in many ways including the 10 examples below:

1.       Helps us improve data security, e.g., by identifying and reporting anomalies that could predict security breaches;
2.       Helps us improve personal security, e.g., by speeding up security screenings at airports, stadiums, concerts, and other venues;
3.       Assists us in financial trading, e.g., with better predictions of what the stock markets will do on any given day;
4.       Helps us with healthcare, e.g., with early detection of breast cancer;
5.       Helps businesses make more sales by marketing personalization, i.e., by helping businesses understand more about their customers;
6.       Assist us in improving fraud detection, e.g., PayPal is using Machine Learning to fight money laundering;
7.       Assists services like Amazon in making accurate/appropriate recommendations regarding what we might want to purchase;
8.       Assist Google in making smart/appropriate responses to our online searches – perhaps the most famous use of Machine Learning;
9.       Assist in translating obscure legalese in contracts into plain language and help attorneys sort through large volumes of information to prepare for a case;
10.   Assist in the functioning of smart cars which are expected to be on the road by 2025.

1.       It’s a big deal: Machine Learning is the rave of the moment;
2.       It’s closely linked to data science: Just as humans learn from experience, Machine Learning systems learn from data;
3.       To become unwary of the dangers of Artificial Intelligence: There is likely to be a positive demand of engineers, come what may.

·         Learn a programming language, e.g., Python
·         Get a high-end PC
·         Learn the prerequisites: Basic Statistics; Basic Linear Algebra; Basic Calculus
·         Read academic papers on Machine Learning
·         Learn from YouTube Videos
·         Read Blogs and Follow Online Communities
·         Practice: Try your hands at Machine Learning projects and participate in contests hosted on Kaggle and similar sites

·         To explore the Machine Learning MOOC on Coursera by Stanford University, please click here
·         To learn how you can get a world-class machine learning education for free, please click here
·         For free, online machine learning courses and MOOCs, please click here
·         To explore Dr. Jason Brownlee’s website on Machine Learning, please click here
·         To explore other MOOCs, please click here


Posted by: Dr. Nat Tuivavalagi

Wednesday, June 21, 2017

Overcoming Challenges of Online Learning


There are various problems with online education that have been brought up.  In particular, “onlinecollege-dot-org” (2012) has described five common challenges of online learning, and how to overcome them:


·         Students may be discouraged by feeling of being on their own.
·         Know that you are not alone!  Take the initiative to reach out to your instructor, classmates, and the many professional services available to support you. Such as:  advisors, counselors, librarians, writing centers, help desks, etc.

·         The need to work with new technology can be very frustrating at first.
·         Gather the contact info for your school’s tech help resources, as well as a few skilled friends for quick access when you need it.

·         Many online students are adding more to their already busy lives by taking courses.  Time management skills are critical to getting everything done.
·         Check each class syllabus for details about “due dates” and add these to your calendar.  Also, practice Time Blocking to get the work completed in advance.  Time Blocking is a productivity “hack” that helps the student make the most of the work day by assigning very specific tasks to very specific blocks of time. This is loosely based on Parkinson’s Law, the idea is that work will simply expand to fill the time available for its completion (Rob Nightingale, philosopher, 12/4/14).

·         Many online students are adults who  work and raise families, and pursuing academic goals after a long absence from school environment may now seems unfamiliar.
·         Look to your instructor to set the tone for the course and consider yourself part of a learning team that includes your teacher, classmates, and the available professional services mentioned in 1) above.

·         There are still some people out there who hold a stereotypical view of online education. They believe it to be cheap, second class option for higher education, reserved for those who are academically or financially weak.  Such people with distorted views on online education may, one day, ask the student discouraging questions about your online education.
·         Be ready to describe how you, (the student) chose your online program. The decision not only  based on flexibility and convenience factors, but also on criteria such as accreditation and faculty qualifications.  Be prepared to list specific ways in which the courses  play a positive role in your overall professional development.


There are  other challenges apart from the five listed above; however, learners who are passionate about what they are studying should be able to find ways to address them.  As they say “where there is a will, there is a way.”

To find an online program suitable for you, please click here.

To find an appropriate free online course or MOOC for you, please click here.


“onlinecollege-dot-org” (2012): How to Overcome the Common Challenges of Online Learning

Rob Nightingale (2014): Time Blocking

Posted by: Dr. Nat Tuivavalagi

Sunday, June 11, 2017



Ruchira Kitsiri a graduate in the medical field , had a clinical practice, then worked across diverse sectors including marketing, sociology, education, mental health, psychology, and cardiology.  His current interest is in genetics and neuroscience, where MOOCs (Massive Open Online Courses) have been very helpful.  In his commentary published in “MOOC News & Reviews” (Kitsiri, 2013), he describes the various groups of people (listed below) who should take a MOOC.  If you, a friend, or family member belong to one of these groups, please kindly advise them to consider enrolling in a MOOC.  In this posting, a “traditional” school refers to the pre-MOOC type that has been dominant over the last hundreds of years, where the main components have been the teacher, the classroom, the school facilities and resources (mostly physical), and the students.


1)      Current Students
All students 13 years old and older taking classes in a traditional setting (including those being home-schooled) up to undergraduate, graduate, and post-graduate levels could benefit from a MOOC:
·         Students can use MOOCs to support their work for the courses they take in their traditional school. MOOCs have Discussion Forums where students can interact with and exchange information, knowledge and experiences with other students.  These interactions could provide inspiration and support for all involved;
·         Some teachers in traditional schools now direct their students to specific MOOCs either to fill in the gaps in the student's’ preparation or to enhance concepts from classes that the teachers are currently teaching.  Even brilliant students sometimes have a weak spot – perhaps Mathematics or Language – that could be  very easily fixed by appropriate MOOCs;
·         Via MOOCs, students can easily gain access to courses not taught in their traditional school.  For example, a law student interested in  a debate regarding whether genes should be patented or not. The student will find a host of biology and genetics MOOCs that could provide essential basic biology and genetics principles that wouldn't be taught in law schools.

2)      Prospective Students
  MOOC is a great place to take a sneak peek into a subject that a prospective student may want to  study.  MOOCs can play a vital role in helping prospective students decide which course or program to take.  This applies to:
·         Current students in high school who have to decide what to study in college or the university;
·         Current students who have to pick one or more electives with little or no understanding of the contents of the elective courses;
·         Current students who are finishing their undergraduate program and have to start thinking of which academic area to focus on for their graduate/postgraduate program;
·         Mothers who want to go back to school after their children have left home.

3)      Research Students
Students pursuing advanced studies sometimes need to refine their focus, identify a specific research topic to work on, select a potential supervisor, and develop a proposal to get funding for a graduate/postgraduate scholarship.  This applies to:
·         High school and undergraduate students working on a student research project;
·         Graduate/postgraduate students working on a research project/paper;
·         Thesis research by undergraduate and graduate/postgraduate students.

4)      Teachers
Teachers can benefit from a MOOC by brushing up and updating their knowledge on the subject and to learn new ways of delivering material to their students.  This applies to:
·         High school or college teachers who have been forced by circumstances to teach a subject at which they are not particularly familiar with  or for which they don’t have a great passion for;
·         High school teachers, college, or university professors who need to strenghten a critical weakness – e.g., a university professor who was hired for his excellence in research but with weakness in his ability to communicate and teach effectively.

5)      Parents
Parents can greatly benefit from MOOCs if they are homeschooling their children or if they are interested in helping out their children – even if the children are attending traditional schools:
·         There are MOOCs that can easily teach parents the subject matters that is needed to help their children;
·         MOOCs can help parents to effectively assist their children's decision on subjects to study.

6)      People Personally Affected By The Issue Covered In A MOOC
People who are  interested in or personally affected by an issue should find out if there is a MOOC on the subject and study the subject if it is available.  Examples include:
·         The MOOC on “Genetics and Evolution” could be useful for those planning to or have obtained genetic services such as: diagnostic tests, risk assessment tests, or legal services that involve genetics; or for those with a concern about a diagnosed genetic disorder;
·         Parents considering vaccination for their children could benefit from one or more of Coursera’s courses dealing with various aspects of vaccination. For Example, “Vaccines” offered by the University of Pennsylvania, and “Vaccine Trials: Methods and Best Practices” by John Hopkins University;
·         Those with aging parents could benefit from “Understanding Dementia” from the University of Tasmania, and “Growing Old Around the Globe” from the University of Pennsylvania;
·         People interested in or personally affected by diabetes could benefit from “Diabetes – A Global Challenge” from the University of Copenhagen.

7)      People Seeking Personal Enrichment At Different Life Stages
People benefitting from MOOCs include those wanting to learn subjects about the world around us, as they were not able to study these things before, due to difficulties with time, money, or access to information.  In some cases, this interest developed recently when people wanted to learn simply for personal satisfaction and fulfilment.  Examples include:
·         A retired psychologist developed an interest in evolution and was inspired to take MOOCs in genetics and biology;
·         A career nutritionist who has always been fascinated by robotics could benefit from “Artificial Intelligence for Robotics,” the MOOC offered on Udacity; and
·         Imagine you want to befriend someone who is heavily into science fiction , an area in which you have very limited if any knowledge about. A possible solution is to take “Fantasy and Science Fiction: The Human Mind, Our Modern World,” the MOOC from the University of Michigan.

8)      Professionals
MOOCs could be the answer for those busy professionals who either want to refresh their subject knowledge or who find themselves requiring knowledge in a subject area different from their own original background qualifications.  Examples include:
·         You may be a member of an interdisciplinary team in evolutionary biology research but you come from a statistic background with no primary qualification in biology.  The MOOC “Introduction to Genetics and Evolution” would help you get a basic introduction to the core principles so you can better relate to your colleagues and to the team’s work;
·         A marketing professional taking up a management role needs to inform herself about finance and could benefit from one or more of available MOOCs.  These include “Introduction to Finance” offered on Coursera by University of Michigan, and “Corporate Finance” also on Coursera by University of Pennsylvania;
·         Consider a practicing lawyer who would like to specialize in the specific area of Environmental Law.  The Coursera MOOC “Introduction to Environmental Law and Policy” from the University of North Carolina at Chapel Hill  may help give a basic idea of the content that may have to be learnt;
·         You may be primarily qualified in the humanities and now work in public health and may want to learn about wider issues that you come across in your day-to-day work.  You would find many MOOCs helpful, including: “Principles of Public Health” from University of California, Irvine, and “Introduction to Global Health” from University of Copenhagen.

9)      Institutional Users
Apart from individuals, institutions can benefit from MOOCs.  Examples include:
·         A small study group from one company that signed up for a public speaking MOOC and meets weekly to work/study  together;
·         Employers can structure the MOOC experience in a way that the certification is recognized within their organization as a valid measure of continuous professional development; and
·         A university department can use some MOOCs in its teaching and training if they do not have the exact expertise on their own faculty.

10)   Other Miscellaneous Categories Of Lifelong Learners
MOOCs could be the best way to move forward for other learners as well, particularly those facing challenges.  Examples include those facing financial, physical, psychological, or social challenges:
·         The poor now have less excuses to receive a good education, as MOOCs offer , high quality courses from top universities at no cost;
·         People with physical disabilities can access quality education from the comfort of their own homes; and
·          Slow learners just have to press the “Replay” button.


In summary, this posting seems to suggest that practically anyone 13 years old or older can benefit from a MOOC. As Kitsiri (2013) pointed out, those who can benefit from a MOOC are limited only by our interest, enthusiasm, and imagination.


To find a MOOC that could benefit you, please click here.


Kitsiri, Ruchira. 2013. Who should take a MOOC?:  9 Types of Lifelong Learners Who Can Benefit. Available online at:

Posted by: Dr. Nat Tuivavalagi