0 1 00:00:00,720 --> 00:00:02,410 Welcome back. 1 2 00:00:02,490 --> 00:00:05,950 Another day, another machine learning module. 2 3 00:00:06,240 --> 00:00:11,710 In this lesson I want to take a brief minute to talk about what we're going to do in this section. 3 4 00:00:11,730 --> 00:00:17,020 So far we've covered one machine learning technique, namely linear regression. 4 5 00:00:17,250 --> 00:00:21,060 And this was with one variable only. And 5 6 00:00:21,090 --> 00:00:25,950 also, we worked through the fundamentals of the Python programming language. 6 7 00:00:26,130 --> 00:00:27,990 So where do we go from here? 7 8 00:00:27,990 --> 00:00:35,280 Well, before we dive deeper into the next projects and tackle more complex machine learning techniques, 8 9 00:00:35,820 --> 00:00:43,320 we've got to peek under the hood and kind of get an understanding of how machine learning actually works. 9 10 00:00:43,320 --> 00:00:47,160 I mean, how does the learning in machine learning actually happen? 10 11 00:00:47,160 --> 00:00:53,640 What are the steps involved and how is it that we can give our computer a whole bunch of data and get 11 12 00:00:53,640 --> 00:00:56,430 back these beautiful parameter estimates? 12 13 00:00:56,460 --> 00:00:59,400 How are these calculations actually made? 13 14 00:00:59,400 --> 00:01:05,610 And to answer these and other utterly fascinating questions, we're going to have to get our hands dirty 14 15 00:01:05,790 --> 00:01:14,270 with some mathematics and some algorithms. And this means getting comfortable and working through a couple 15 16 00:01:14,270 --> 00:01:16,240 of difficult concepts. 16 17 00:01:16,400 --> 00:01:21,800 And that includes this idea of optimization, mathematical optimization. 17 18 00:01:21,800 --> 00:01:27,230 So you've probably already guessed that this section is going to be a bit more technical than the previous 18 19 00:01:27,230 --> 00:01:28,370 modules. 19 20 00:01:28,520 --> 00:01:30,650 We're going to be doing some calculus. 20 21 00:01:30,680 --> 00:01:33,830 We're going to work with derivatives and partial derivatives. 21 22 00:01:33,830 --> 00:01:39,290 We're going to be doing some more advanced programming Python too, because we're gonna be using loops and 22 23 00:01:39,290 --> 00:01:46,370 we're going to write our own optimization algorithm from scratch. And the optimization algorithm in question 23 24 00:01:46,730 --> 00:01:49,760 is called Gradient Descent. 24 25 00:01:49,760 --> 00:01:56,240 And once we've done all that, we're gonna apply this algorithm to various problems and see how it behaves. 25 26 00:01:57,140 --> 00:02:03,470 And what I mean by that is - in what situations does the algorithm do well? And when does this algorithm 26 27 00:02:03,470 --> 00:02:05,540 fall flat on its face? 27 28 00:02:05,570 --> 00:02:08,520 What are the strengths and weaknesses of the approach? 28 29 00:02:08,540 --> 00:02:10,620 What is the algorithm sensitive to? 29 30 00:02:10,850 --> 00:02:18,140 And does our algorithm have an allergy to peanuts? And all this will help us build an understanding of 30 31 00:02:18,140 --> 00:02:21,510 how machine learning actually works from the ground up. 31 32 00:02:21,680 --> 00:02:27,380 And if we want to be able to understand the more complex machine learning techniques like neural networks 32 33 00:02:27,620 --> 00:02:32,750 and tackle the more difficult projects, we're going to have to build up an understanding of how these 33 34 00:02:32,750 --> 00:02:36,490 techniques work to arrive at a solution in the first place. 34 35 00:02:37,760 --> 00:02:40,010 And that about covers the intro. 35 36 00:02:40,010 --> 00:02:41,470 I'll see you in the next lesson.