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+---
+status: seed
+type: concept
+tags: []
+created: 2025-12-17
+updated: 2026-04-24
+title: Обратное распространение ошибки - вывод
+---
+
+# Обратное распространение ошибки - вывод
+
+> [!note] Обозначения
+> $x_{j}$ - $j$-ый вход
+> $w_{ij}^{(1)}$ - вес от входа $j$ к скрытому нейрону $i$
+> $w_{li}^{(2)}$ - вес от скрытого нейрона $i$ к выходу $l$
+> $S_{i}^{(1)}$ - взвешенная сумма на входе нейрона $i$ в слое *1*
+> $u_{i}$ - выход нейрона $i$ слоя *1* (после активации)
+> $S_{l}^{(2)}$ - взвешенная сумма на входе нейрона $l$ слоя *2*
+> $y_{l}$ - выход нейрона $l$ слоя *2* (предсказание)
+> $d_{l}$ - истинное значение
+> $F$ - функция активации (напр. сигмоида) 
+
+## Прямой проход
+$$\begin{align*}
+&S_{i}^{(1)} = \sum\limits_{j=1}^{n}w_{ij}^{(1)}x_{j} \text{ - взвешенная сумма на первом слое}\\
+&u_{i}=F(S_{i}^{(1)}) \\
+&y_{l}=F(s_{l}^{(2)}) \\
+&E = \frac{1}{2}*\sum\limits_{l=1}^{m}(y_{l}-d_{l})^{2}
+\end{align*}$$
+## Обратный проход (выходной слой)
+$$\begin{align*} 
+\frac{dE}{dw_{li}^{(2)}}&=\frac{dE}{dy_{l}}* \frac{dy_{l}}{dS_{l}^{(2)}}*\frac{dS_{l}^{(2)}}{dw_{li}^{(2)}}\\
+\end{align*}$$
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+---
+status: seed
+type: concept
+tags: []
+created: 2025-12-17
+updated: 2026-05-07
+title: Статья на английский
+---
+
+# Статья на английский
+
+## **GameStop Wants to Buy eBay**
+
+GameStop is a well-known retail company that sells video games. A few years ago, it was losing money and closing stores. But its CEO Ryan Cohen is an **ambitious entrepreneur** who had a plan. He used the company's cash to invest, and now GameStop has nearly $9 billion in savings.
+
+This week, GameStop made a surprising offer to buy eBay for $56 billion. The offer gives eBay **shareholders** $125 per **share** — about 20% more than the current price. Cohen is **optimistic**: he believes eBay is undervalued and could bring strong **returns**. He wants to turn it into a business worth hundreds of billions. To fund the deal, a bank agreed to provide nearly $20 billion.
+
+However, many **traders** and analysts think the move is **reckless**. It is hard to **assess** this deal as realistic — GameStop is worth only $12 billion, while eBay is worth $46 billion. Buying a company four times bigger than yourself is a huge **venture**. The market agrees: eBay's **stock** only rose to $113, far below the $125 offer. People are **pessimistic** that the deal will actually happen.