In a past blog post,
I defined and described what machine learning is. I briefly highlighted four
instances where machine learning algorithms are useful. This is what I wrote:
- Autonomy:
To teach computers to do a task without the direct aid/intervention of humans
(e.g. autonomous vehicles)
- Fluctuation:
Help machines adjust when the requirements and data change over time
- Intuitive
Processing: Conduct or assist in tasks humans do but
are unable to explain how computationally/algorithmically (e.g. image
recognition)
- Big
Data: Breaking down data that is too large to handle
otherwise
The goal of this blog
post is to explain each in more detail.
Case
#1: Autonomy
The first major use of
machine learning centers around teaching computers to do a task or tasks
without the direct aid or intervention of humans. Self-driving vehicles are a
high-profile example of this: teaching a vehicle to drive (scanning the road and
determining how to respond to what is around it) without the aid of or with
minimal direct oversight from a human driver.
There are two types basic
types of tasks that machine learning systems might perform autonomously:
- Tasks humans frequently perform
- Tasks humans are unable to perform.
Self-driving cars
exemplify the former: humans drive cars, but self-driving cars would perform
all or part of the driving process. Another example would be chatbots and
virtual assistants like Alexa, Cortana, and Ok Google, which seek to converse
with users independently. Such tasks might completely or partially complete the
human activity: for example, some customer service chatbots are designed to
determine the customer’s issue but then to transfer to a human when the issue
has a certain complexity.
Humans have also sought
to build autonomous machine learning algorithms to perform tasks that humans
are unable to perform. Unlike self-driving cars, which conduct an activity many
people do, people might also design a self-driving rover or submarine to drive
and operate in a world that humans have so far been unable to inhabit, like other
planets in our Solar System or the deep ocean. Search engines are another
example: Google uses machine learning to help refine search results, which
involves analyzing a massive amount of web data beyond what a human could
normally do.
Case
#2: Fluctuating Data
Machine learning is also
powerful tool for making sense of and incorporating fluctuating data. Unlike
other types of models with fixed processes for how it predicts its values,
machine learning models can learn from current patterns and adjust both if the
patterns fluctuate overtime or if new use cases arise. This can be especially
helpful when trying to forecast the future, allowing the model to decipher new trends
if and when they emerge. For example, when predicting stock prices, machine
learning algorithms can learn from new data and pick up changing trends to make
the model better at predicting the future.
Of course, humans are
notorious for changing overtime, so fluctuation is often helpful in models that
seek to understand human preferences and behavior. For example, user
recommendations – like Netflix’s, Hulu’s, or YouTube’s video recommendation
systems – adjust based on the usage overtime, enabling them to respond to individual
and/or collective changes in interests.
Case
#3: Intuitive Processing
Data scientist frequently
develop machine learning algorithms to teach computers how to do processes that
humans do naturally but for which we are unable to fully explain how
computationally. For example, popular applications of machine learning center
around replicating some aspect of sensory perception: image recognition, sound
or speech recognition, etc. These replicate the process of inputting sensory
information (e.g. sight and sound) and processing, classifying, and otherwise
making sense of that information. Language processing, like chatbots, form
another example of this. In these contexts, machine learning algorithms learn a
process that humans can do intuitively (see or hear stimuli and understand
language) but are unable to fully explain how or why.
Many early forms of
machine learning arose out of neurological models of how human brains work. The
initial intention of neural nets, for instance, were to model our neurological
decision-making process or processes. Now, much contemporary neurological
scholarship since has disproven the accuracy of neural nets in representing how
our brains and minds work.[i] But, whether they
represent how human minds work at all, neural networks have provided a powerful
technique for computers to use to process and classify information and make
decisions. Likewise, many machine learning algorithms replicate some activity
humans do naturally, even if the way they conduct that human task has little to
do with how humans would.
Case
#4: Big Data
Machine learning is a
powerful tool when analyzing data that is too large to break down through
conventional computational techniques. Recent computer technologies have
increased the possibility of data collection, storage, and processing, a major
driver in big data. Machine learning has arisen as a major, if not the major,
means of analyzing this big data.
Machine learning
algorithms can manage a dizzying array of variables and use them to find insightful
patterns (like lasso regression for linear modeling). Many big data cases
involve hundreds, thousands, and maybe even tens or hundreds of thousands of
input variables, and many machine learning techniques (like best subsets
selection, stepwise selection, and lasso regression) process the myriads of
variables in big data and determine the best ones to use.
Recent developments
computing provides the incredible processing power necessary to do such work
(and debatably, machine learning is currently helping to push computational power
and provide a demand for greater computational abilities). Hand-calculations
and computers several decades ago were often unable to handle the calculations
necessary to analyze large information: demonstrated, for example, by the fact
that computer scientists invented the now popular neural networks many decades
ago, but they did not gain popularity as a method until recent computer
processing made them easy and worthwhile to run.
Tractors and other
large-scale agricultural techniques coincided historically with the enlargement
of farm property sizes, where the such machinery not only allowed farmers to manage
large tracks of land but also incentivized larger farms economically. Likewise,
machine learning algorithms provide the main technological means to analyze big
data, both enabling and in turn incentivized by rise of big data in the
professional world.
Conclusion
Here I have described
four major uses of machine learning algorithms. Machine learning has become
popular in many industries because of at least one of these functionalities, but
of course, they are not the only potential current uses. In addition, as we
develop machine learning tools, we are constantly inventing more. Given machine
learning’s newness compared to many other century-old technologies, time will
tell all the ways humans utilize it.
Photo credit #1: Mike MacKenzie at https://www.flickr.com/photos/mikemacmarketing/30212411048/
Photo credit #2: julientromeur at https://pixabay.com/illustrations/car-automobile-3d-self-driving-4343635/
Photo credit #3: geralt at https://pixabay.com/illustrations/business-success-curve-hand-draw-1989130/
Photo credit #4: geralt at https://pixabay.com/illustrations/flat-recognition-facial-face-woman-3252983/
Photo credit #5: mohamed_hassan at https://pixabay.com/illustrations/technology-5g-aerial-4816658/
[i] See Richard, Nagyfi. The differences between Artificial and Biological Neural Networks. 4 September 2018. https://towardsdatascience.com/the-differences-between-artificial-and-biological-neural-networks-a8b46db828b7; and Tcheang, Lili. Are Artificial Neural Networks like the Human Brain? And does it matter? 7 November 2018. https://medium.com/digital-catapult/are-artificial-neural-networks-like-the-human-brain-and-does-it-matter-3add0f029273.