why is it bad if elastic-net regularization is used? what is the residual for needle-in-a-haystack regularization what is regularized regression why does the model generate large residuals when $f=1$ what is the model that is unbiased in ols what is needle in a haystack regularization ols definition of random variable what is needle in a haystack regularized regression what makes an elastic network regular what type of model does regularization generate when to regularize a model in elastic-net regression when does the ols model generate residuals when a model is regularized what is a needle in a haystack regularized regression model why is it important to use elastic-net regularization when using a continuous model when to use needle-in-a-haystack regularization why is regularization used in model development what is needle in a haystack regularization what is needle-in-a-haystack regularization what makes a regularized model of a linear model noisy