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world:quiz4 [2025/10/03 18:16]
francois_bertholom ↷ Page moved from emines2024:quiz4 to world:quiz4
world:quiz4 [2025/10/06 09:30] (current)
rdouc
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  Which of the following statements are true?   Which of the following statements are true? 
    
-  * 1. Assume that $n=3$, the situation where we have $(h^2_{12},​h^2_{13})=(0.2,​0.2)$ is impossible. ​  +  * 1. Assume that $n=3$, the situation where we have $(h^2_{12},​h^2_{13})=(0.2,​0.2)$ is impossible. ​**TRUE** ​ 
-  * 2. The situation where $h_{ii}=0.5$,​ and for all $j\neq i$, $h_{ij}=0$ may happen sometimes.  +  * 2. The situation where $h_{ii}=0.5$,​ and for all $j\neq i$, $h_{ij}=0$ may happen sometimes. ​**FALSE** 
-  * 3. If $\epsilon \sim N(0,​\sigma^2 I_n)$ and if the (external) studentized residual $t_i^*$ satisfies $t_i^*<​-2$,​ then we consider that $(x'​_i,​y_i)$ is a leverage point. ​+  * 3. If $\epsilon \sim N(0,​\sigma^2 I_n)$ and if the (external) studentized residual $t_i^*$ satisfies $t_i^*<​-2$,​ then we consider that $(x'​_i,​y_i)$ is a leverage point. ​**FALSE**
  
 ===== Exercise 2: Hoeffding'​s inequality ===== ===== Exercise 2: Hoeffding'​s inequality =====
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 Let $(X_i)_{1\leq i \leq n}$ be iid random variables such that $\PP(X_1 \in [0,1])=1$. Which of the following statements are true?  Let $(X_i)_{1\leq i \leq n}$ be iid random variables such that $\PP(X_1 \in [0,1])=1$. Which of the following statements are true? 
  
-  * 4. According to Hoeffding'​s inequality, $\PP\lr{\left|\frac{\sum_{i=1}^n X_i}{n} - \PE[X]\right| > \epsilon} \leq 2 \rme^{-2 \epsilon^2/​n}$  +  * 4. According to Hoeffding'​s inequality, $\PP\lr{\left|\frac{\sum_{i=1}^n X_i}{n} - \PE[X]\right| > \epsilon} \leq 2 \rme^{-2 \epsilon^2/​n}$ ​**FALSE** 
-  * 5. According to Hoeffding'​s inequality, $\PP\lr{\left|\frac{\sum_{i=1}^n X_i}{n} - \PE[X]\right| > \epsilon} \leq 2 \rme^{-2 n^2\epsilon^2}$  +  * 5. According to Hoeffding'​s inequality, $\PP\lr{\left|\frac{\sum_{i=1}^n X_i}{n} - \PE[X]\right| > \epsilon} \leq 2 \rme^{-2 n^2\epsilon^2}$ ​**FALSE** 
-  * 6. According to Hoeffding'​s inequality, $\PP\lr{\left|\sum_{i=1}^n (X_i - \PE[X])\right| > \epsilon} \leq 2 \rme^{-2 n\epsilon^2}$ ​+  * 6. According to Hoeffding'​s inequality, $\PP\lr{\left|\sum_{i=1}^n (X_i - \PE[X])\right| > \epsilon} \leq 2 \rme^{-2 n\epsilon^2}$ ​**FALSE**
  
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world/quiz4.txt · Last modified: 2025/10/06 09:30 by rdouc