**Daily update | 28 September, 2022**

# StackExchange

#### Why does degrees of freedom = $\frac{\operatorname{Tr}(H'H)^2}{\operatorname{Tr}(H'HH'H)}$?

**Source:** stats**Views:** 60**Score:** 4**Tags:** regression degrees-of-freedom

#### Why doesn't R use Inverse Transform Sampling to sample from the Exponential Distribution?

**Source:** stats**Views:** 41**Score:** 4**Tags:** sampling

#### How to motivate the definition of $R^2$ in `sklearn.metrics.r2_score`?

**Source:** stats**Views:** 50**Score:** 4**Tags:** regression python scikit-learn r-squared

#### Why Deep Learning needs to be performed in Graphical representations?

**Source:** stats**Views:** 22**Score:** 3**Tags:** machine-learning neural-networks graph-theory graph-neural-network

#### AIC for nested models: is the AIC of a smaller model A always smaller than that of the nesting model B?

**Source:** stats**Views:** 202**Score:** 2**Tags:** modeling aic nested-models