I'm writing this review belatedly. Before Chapter 4 appeared, I had thoughts like "private companies don't even do this much." I also thought "isn't this just the basics that everyone does?" However, after seeing the inference and future data forecasting in Chapter 4, I was able to find the basis for the data estimation and forecasting I had been doing. Furthermore, the introduction to several techniques was also good. I think Chapter 4 felt fresh because there were parts I didn't know about. Depending on the level of the students taking this course, the lecture can feel either fresh or mundane (sorry?). However, I think you'll be able to acquire at least 1-2 work know-hows that you need, especially those that don't circulate well on the internet or those where you don't know the reasoning behind them even if they do circulate. Like the example in Chapter 4, if other chapters are reinforced and future chapters are enhanced, I think the price will increase even more. Additionally, while taking this course, I gained hope and a concept that I could create a lecture about the work I do and have done. It seems like a lecture worth taking in many ways. I don't know how it will be updated in the future. Still, since this lecture has a high possibility of becoming Jaesung's 'signature course,' I think there's a high possibility of future updates.