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0 6480 Machine learning. Teach a computer how to perform a task, without explicitly programming it to perform said task.
6620 13420 Instead, feed data into an algorithm to gradually improve outcomes with experience, similar to how organic life learns.
13580 20400 The term was coined in 1959 by Arthur Samuel at IBM, who was developing artificial intelligence that could play checkers.
20540 26880 Half a century later, and predictive models are embedded in many of the products we use every day, which perform two fundamental jobs.
26880 32040 One is to classify data, like "Is there another car on the road?" or "Does this patient have cancer?"
32040 38600 The other is to make predictions about future outcomes, like "Will this stock go up?" or "Which YouTube video do you want to watch next?"
38600 43280 The first step in the process is to acquire and clean up data. Lots and lots of data.
43480 47780 The better the data represents the problem, the better the results. Garbage in, garbage out.
47900 52160 The data needs to have some kind of signal to be valuable to the algorithm for making predictions.
52160 59920 And data scientists perform a job called feature engineering to transform raw data into features that better represent the underlying problem.
60240 64240 The next step is to separate the data into a training set and testing set.
64460 71800 The training data is fed into an algorithm to build a model, then the testing data is used to validate the accuracy or error of the model.
71980 77700 The next step is to choose an algorithm, which might be a simple statistical model like linear or logistic regression,
77940 81260 or a decision tree that assigns different weights to features in the data.
81260 86640 Or you might get fancy with a convolutional neural network, which is an algorithm that also assigns
86640 91300 weights to features, but also takes the input data and creates additional features automatically.
91640 96300 And that's extremely useful for datasets that contain things like images or natural language,
96420 99020 where manual feature engineering is virtually impossible.
99260 103960 Every one of these algorithms learns to get better by comparing its predictions to an error function.
104160 109840 If it's a classification problem, like "Is this animal a cat or a dog?" the error function might be accuracy.
109840 115900 If it's a regression problem, like "How much will a loaf of bread cost next year?" then it might be mean absolute error.
116220 121780 Python is the language of choice among data scientists, but R and Julia are also popular options,
121920 125320 and there are many supporting frameworks out there to make the process approachable.
125500 132680 The end result of the machine learning process is a model, which is just a file that takes some input data in the same shape that it was trained on,
132860 136900 then spits out a prediction that tries to minimize the error that it was optimized for.
136900 141980 It can then be embedded on an actual device or deployed to the cloud to build a real-world product.
142180 144500 This has been Machine Learning in 100 Seconds.
144580 147160 Like and subscribe if you want to see more short videos like this,
147320 150500 and leave a comment if you want to see more machine learning content on this channel.
150620 153040 Thanks for watching, and I will see you in the next one.
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