updating weel 36
This commit is contained in:
@@ -85,6 +85,8 @@ Automatically generated HTML file from DocOnce source
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'simple-example-to-illustrate-ordinary-least-squares-ridge-and-lasso-regression'),
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('Ridge Regression', 2, None, 'ridge-regression'),
|
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('Lasso Regression', 2, None, 'lasso-regression'),
|
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('Yet another Example', 2, None, 'yet-another-example'),
|
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('The OLS case', 2, None, 'the-ols-case'),
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('Linking the regression analysis with a statistical '
|
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'interpretation',
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2,
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@@ -241,38 +243,40 @@ MathJax.Hub.Config({
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<!-- navigation toc: --> <li><a href="._week36-bs014.html#simple-example-to-illustrate-ordinary-least-squares-ridge-and-lasso-regression" style="font-size: 80%;">Simple example to illustrate Ordinary Least Squares, Ridge and Lasso Regression</a></li>
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<!-- navigation toc: --> <li><a href="._week36-bs015.html#ridge-regression" style="font-size: 80%;">Ridge Regression</a></li>
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||||
<!-- navigation toc: --> <li><a href="._week36-bs016.html#lasso-regression" style="font-size: 80%;">Lasso Regression</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs017.html#linking-the-regression-analysis-with-a-statistical-interpretation" style="font-size: 80%;">Linking the regression analysis with a statistical interpretation</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs018.html#assumptions-made" style="font-size: 80%;">Assumptions made</a></li>
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||||
<!-- navigation toc: --> <li><a href="._week36-bs019.html#expectation-value-and-variance" style="font-size: 80%;">Expectation value and variance</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs020.html#expectation-value-and-variance-for-boldsymbol-beta" style="font-size: 80%;">Expectation value and variance for \( \boldsymbol{\beta} \)</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs021.html#friday-september-10" style="font-size: 80%;">Friday September 10</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs025.html#why-resampling-methods" style="font-size: 80%;">Why resampling methods</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs027.html#resampling-methods" style="font-size: 80%;">Resampling methods</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs024.html#resampling-approaches-can-be-computationally-expensive" style="font-size: 80%;">Resampling approaches can be computationally expensive</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs025.html#why-resampling-methods" style="font-size: 80%;">Why resampling methods ?</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs026.html#statistical-analysis" style="font-size: 80%;">Statistical analysis</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs027.html#resampling-methods" style="font-size: 80%;">Resampling methods</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs028.html#resampling-methods-jackknife-and-bootstrap" style="font-size: 80%;">Resampling methods: Jackknife and Bootstrap</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs029.html#resampling-methods-jackknife" style="font-size: 80%;">Resampling methods: Jackknife</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs030.html#jackknife-code-example" style="font-size: 80%;">Jackknife code example</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs031.html#resampling-methods-bootstrap" style="font-size: 80%;">Resampling methods: Bootstrap</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs032.html#resampling-methods-bootstrap-background" style="font-size: 80%;">Resampling methods: Bootstrap background</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs033.html#resampling-methods-more-bootstrap-background" style="font-size: 80%;">Resampling methods: More Bootstrap background</a></li>
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||||
<!-- navigation toc: --> <li><a href="._week36-bs034.html#resampling-methods-bootstrap-approach" style="font-size: 80%;">Resampling methods: Bootstrap approach</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs035.html#resampling-methods-bootstrap-steps" style="font-size: 80%;">Resampling methods: Bootstrap steps</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs036.html#code-example-for-the-bootstrap-method" style="font-size: 80%;">Code example for the Bootstrap method</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs037.html#various-steps-in-cross-validation" style="font-size: 80%;">Various steps in cross-validation</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs038.html#how-to-set-up-the-cross-validation-for-ridge-and-or-lasso" style="font-size: 80%;">How to set up the cross-validation for Ridge and/or Lasso</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs039.html#cross-validation-in-brief" style="font-size: 80%;">Cross-validation in brief</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs040.html#code-example-for-cross-validation-and-k-fold-cross-validation" style="font-size: 80%;">Code Example for Cross-validation and \( k \)-fold Cross-validation</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs041.html#the-bias-variance-tradeoff" style="font-size: 80%;">The bias-variance tradeoff</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs042.html#example-code-for-bias-variance-tradeoff" style="font-size: 80%;">Example code for Bias-Variance tradeoff</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs043.html#understanding-what-happens" style="font-size: 80%;">Understanding what happens</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs044.html#summing-up" style="font-size: 80%;">Summing up</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs045.html#another-example-from-scikit-learn-s-repository" style="font-size: 80%;">Another Example from Scikit-Learn's Repository</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs046.html#more-examples-on-bootstrap-and-cross-validation-and-errors" style="font-size: 80%;">More examples on bootstrap and cross-validation and errors</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs047.html#the-same-example-but-now-with-cross-validation" style="font-size: 80%;">The same example but now with cross-validation</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs048.html#cross-validation-with-ridge" style="font-size: 80%;">Cross-validation with Ridge</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs017.html#yet-another-example" style="font-size: 80%;">Yet another Example</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs018.html#the-ols-case" style="font-size: 80%;">The OLS case</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs019.html#linking-the-regression-analysis-with-a-statistical-interpretation" style="font-size: 80%;">Linking the regression analysis with a statistical interpretation</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs020.html#assumptions-made" style="font-size: 80%;">Assumptions made</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs021.html#expectation-value-and-variance" style="font-size: 80%;">Expectation value and variance</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs022.html#expectation-value-and-variance-for-boldsymbol-beta" style="font-size: 80%;">Expectation value and variance for \( \boldsymbol{\beta} \)</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs023.html#friday-september-10" style="font-size: 80%;">Friday September 10</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs027.html#why-resampling-methods" style="font-size: 80%;">Why resampling methods</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs029.html#resampling-methods" style="font-size: 80%;">Resampling methods</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs026.html#resampling-approaches-can-be-computationally-expensive" style="font-size: 80%;">Resampling approaches can be computationally expensive</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs027.html#why-resampling-methods" style="font-size: 80%;">Why resampling methods ?</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs028.html#statistical-analysis" style="font-size: 80%;">Statistical analysis</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs029.html#resampling-methods" style="font-size: 80%;">Resampling methods</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs030.html#resampling-methods-jackknife-and-bootstrap" style="font-size: 80%;">Resampling methods: Jackknife and Bootstrap</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs031.html#resampling-methods-jackknife" style="font-size: 80%;">Resampling methods: Jackknife</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs032.html#jackknife-code-example" style="font-size: 80%;">Jackknife code example</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs033.html#resampling-methods-bootstrap" style="font-size: 80%;">Resampling methods: Bootstrap</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs034.html#resampling-methods-bootstrap-background" style="font-size: 80%;">Resampling methods: Bootstrap background</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs035.html#resampling-methods-more-bootstrap-background" style="font-size: 80%;">Resampling methods: More Bootstrap background</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs036.html#resampling-methods-bootstrap-approach" style="font-size: 80%;">Resampling methods: Bootstrap approach</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs037.html#resampling-methods-bootstrap-steps" style="font-size: 80%;">Resampling methods: Bootstrap steps</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs038.html#code-example-for-the-bootstrap-method" style="font-size: 80%;">Code example for the Bootstrap method</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs039.html#various-steps-in-cross-validation" style="font-size: 80%;">Various steps in cross-validation</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs040.html#how-to-set-up-the-cross-validation-for-ridge-and-or-lasso" style="font-size: 80%;">How to set up the cross-validation for Ridge and/or Lasso</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs041.html#cross-validation-in-brief" style="font-size: 80%;">Cross-validation in brief</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs042.html#code-example-for-cross-validation-and-k-fold-cross-validation" style="font-size: 80%;">Code Example for Cross-validation and \( k \)-fold Cross-validation</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs043.html#the-bias-variance-tradeoff" style="font-size: 80%;">The bias-variance tradeoff</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs044.html#example-code-for-bias-variance-tradeoff" style="font-size: 80%;">Example code for Bias-Variance tradeoff</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs045.html#understanding-what-happens" style="font-size: 80%;">Understanding what happens</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs046.html#summing-up" style="font-size: 80%;">Summing up</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs047.html#another-example-from-scikit-learn-s-repository" style="font-size: 80%;">Another Example from Scikit-Learn's Repository</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs048.html#more-examples-on-bootstrap-and-cross-validation-and-errors" style="font-size: 80%;">More examples on bootstrap and cross-validation and errors</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs049.html#the-same-example-but-now-with-cross-validation" style="font-size: 80%;">The same example but now with cross-validation</a></li>
|
||||
<!-- navigation toc: --> <li><a href="._week36-bs050.html#cross-validation-with-ridge" style="font-size: 80%;">Cross-validation with Ridge</a></li>
|
||||
|
||||
</ul>
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||||
</li>
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||||
@@ -331,7 +335,7 @@ MathJax.Hub.Config({
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<li><a href="._week36-bs008.html">9</a></li>
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<li><a href="._week36-bs009.html">10</a></li>
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<li><a href="">...</a></li>
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<li><a href="._week36-bs048.html">49</a></li>
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<li><a href="._week36-bs050.html">51</a></li>
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<li><a href="._week36-bs001.html">»</a></li>
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</ul>
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<!-- ------------------- end of main content --------------- -->
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@@ -662,6 +662,51 @@ We will amongst other things show that the regularization parameter can reduce c
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</section>
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<section>
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<h2 id="yet-another-example">Yet another Example </h2>
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<p>
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Let us assume we have a data set with outputs/targets given by the vector
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<p> <br>
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$$
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\boldsymbol{y}=\begin{matrix}4 \\ 2 \\3\end{bmatrix},
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$$
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<p> <br>
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and our inputs as a \( 3\times 2 \) design matrix
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<p> <br>
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$$
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\boldsymbol{X}=\begin{matrix}2 & 0\\ 0 & 1 \\ 1 & 0\end{bmatrix},
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$$
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<p> <br>
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meaning that we have two features and two unknown parameters \( \beta_0 \) and \( \beta_1 \) to be determined either by ordinary least squares, Ridge or Lasso regression.
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</section>
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<section>
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<h2 id="the-ols-case">The OLS case </h2>
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<p>
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For ordinary least squares (OLS) we know that the optimal solution is
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<p> <br>
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$$
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\hat{\boldsymbol{\beta}}=\left( \boldsymbol{X}^T\boldsymbol{X}\right)^{-1}\boldsymbol{X}^T\boldsymbol{y}.
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$$
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<p> <br>
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Inserting the above values we obtain that
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<p> <br>
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$$
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\hat{\boldsymbol{\beta}}=\begin{matrix}\frac{11}{5} \\ 2\end{bmatrix},
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$$
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<p> <br>
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</section>
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<section>
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<h2 id="linking-the-regression-analysis-with-a-statistical-interpretation">Linking the regression analysis with a statistical interpretation </h2>
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@@ -105,6 +105,8 @@ div { text-align: justify; text-justify: inter-word; }
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'simple-example-to-illustrate-ordinary-least-squares-ridge-and-lasso-regression'),
|
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('Ridge Regression', 2, None, 'ridge-regression'),
|
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('Lasso Regression', 2, None, 'lasso-regression'),
|
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('Yet another Example', 2, None, 'yet-another-example'),
|
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('The OLS case', 2, None, 'the-ols-case'),
|
||||
('Linking the regression analysis with a statistical '
|
||||
'interpretation',
|
||||
2,
|
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@@ -676,6 +678,43 @@ Plotting these results (figure to come) shows clearly that Lasso regression supp
|
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We will now couple the discussions of ordinary least squares, Ridge and Lasso regression with a statistical interpretation, that is we move from a linear algebra analysis to a statistical analysis. In particular, we will focus on what the regularization terms can result in.
|
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We will amongst other things show that the regularization parameter can reduce considerably the variance of the parameters \( \beta \).
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|
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<p>
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<!-- !split --><br><br><br><br><br><br><br><br><br><br>
|
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|
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<h2 id="yet-another-example">Yet another Example </h2>
|
||||
|
||||
<p>
|
||||
Let us assume we have a data set with outputs/targets given by the vector
|
||||
|
||||
$$
|
||||
\boldsymbol{y}=\begin{matrix}4 \\ 2 \\3\end{bmatrix},
|
||||
$$
|
||||
|
||||
and our inputs as a \( 3\times 2 \) design matrix
|
||||
$$
|
||||
\boldsymbol{X}=\begin{matrix}2 & 0\\ 0 & 1 \\ 1 & 0\end{bmatrix},
|
||||
$$
|
||||
|
||||
meaning that we have two features and two unknown parameters \( \beta_0 \) and \( \beta_1 \) to be determined either by ordinary least squares, Ridge or Lasso regression.
|
||||
|
||||
<p>
|
||||
<!-- !split --><br><br><br><br><br><br><br><br><br><br>
|
||||
|
||||
<h2 id="the-ols-case">The OLS case </h2>
|
||||
|
||||
<p>
|
||||
For ordinary least squares (OLS) we know that the optimal solution is
|
||||
|
||||
$$
|
||||
\hat{\boldsymbol{\beta}}=\left( \boldsymbol{X}^T\boldsymbol{X}\right)^{-1}\boldsymbol{X}^T\boldsymbol{y}.
|
||||
$$
|
||||
|
||||
Inserting the above values we obtain that
|
||||
|
||||
$$
|
||||
\hat{\boldsymbol{\beta}}=\begin{matrix}\frac{11}{5} \\ 2\end{bmatrix},
|
||||
$$
|
||||
|
||||
<p>
|
||||
<!-- !split -->
|
||||
|
||||
|
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@@ -110,6 +110,8 @@ div { text-align: justify; text-justify: inter-word; }
|
||||
'simple-example-to-illustrate-ordinary-least-squares-ridge-and-lasso-regression'),
|
||||
('Ridge Regression', 2, None, 'ridge-regression'),
|
||||
('Lasso Regression', 2, None, 'lasso-regression'),
|
||||
('Yet another Example', 2, None, 'yet-another-example'),
|
||||
('The OLS case', 2, None, 'the-ols-case'),
|
||||
('Linking the regression analysis with a statistical '
|
||||
'interpretation',
|
||||
2,
|
||||
@@ -681,6 +683,43 @@ Plotting these results (figure to come) shows clearly that Lasso regression supp
|
||||
We will now couple the discussions of ordinary least squares, Ridge and Lasso regression with a statistical interpretation, that is we move from a linear algebra analysis to a statistical analysis. In particular, we will focus on what the regularization terms can result in.
|
||||
We will amongst other things show that the regularization parameter can reduce considerably the variance of the parameters \( \beta \).
|
||||
|
||||
<p>
|
||||
<!-- !split --><br><br><br><br><br><br><br><br><br><br>
|
||||
|
||||
<h2 id="yet-another-example">Yet another Example </h2>
|
||||
|
||||
<p>
|
||||
Let us assume we have a data set with outputs/targets given by the vector
|
||||
|
||||
$$
|
||||
\boldsymbol{y}=\begin{matrix}4 \\ 2 \\3\end{bmatrix},
|
||||
$$
|
||||
|
||||
and our inputs as a \( 3\times 2 \) design matrix
|
||||
$$
|
||||
\boldsymbol{X}=\begin{matrix}2 & 0\\ 0 & 1 \\ 1 & 0\end{bmatrix},
|
||||
$$
|
||||
|
||||
meaning that we have two features and two unknown parameters \( \beta_0 \) and \( \beta_1 \) to be determined either by ordinary least squares, Ridge or Lasso regression.
|
||||
|
||||
<p>
|
||||
<!-- !split --><br><br><br><br><br><br><br><br><br><br>
|
||||
|
||||
<h2 id="the-ols-case">The OLS case </h2>
|
||||
|
||||
<p>
|
||||
For ordinary least squares (OLS) we know that the optimal solution is
|
||||
|
||||
$$
|
||||
\hat{\boldsymbol{\beta}}=\left( \boldsymbol{X}^T\boldsymbol{X}\right)^{-1}\boldsymbol{X}^T\boldsymbol{y}.
|
||||
$$
|
||||
|
||||
Inserting the above values we obtain that
|
||||
|
||||
$$
|
||||
\hat{\boldsymbol{\beta}}=\begin{matrix}\frac{11}{5} \\ 2\end{bmatrix},
|
||||
$$
|
||||
|
||||
<p>
|
||||
<!-- !split -->
|
||||
|
||||
|
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Binary file not shown.
@@ -778,7 +778,76 @@
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"We will amongst other things show that the regularization parameter can reduce considerably the variance of the parameters $\\beta$.\n",
|
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"\n",
|
||||
"\n",
|
||||
"## Yet another Example\n",
|
||||
"\n",
|
||||
"Let us assume we have a data set with outputs/targets given by the vector"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"$$\n",
|
||||
"\\boldsymbol{y}=\\begin{matrix}4 \\\\ 2 \\\\3\\end{bmatrix},\n",
|
||||
"$$"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"and our inputs as a $3\\times 2$ design matrix"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"$$\n",
|
||||
"\\boldsymbol{X}=\\begin{matrix}2 & 0\\\\ 0 & 1 \\\\ 1 & 0\\end{bmatrix},\n",
|
||||
"$$"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"meaning that we have two features and two unknown parameters $\\beta_0$ and $\\beta_1$ to be determined either by ordinary least squares, Ridge or Lasso regression.\n",
|
||||
"\n",
|
||||
"## The OLS case\n",
|
||||
"\n",
|
||||
"For ordinary least squares (OLS) we know that the optimal solution is"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"$$\n",
|
||||
"\\hat{\\boldsymbol{\\beta}}=\\left( \\boldsymbol{X}^T\\boldsymbol{X}\\right)^{-1}\\boldsymbol{X}^T\\boldsymbol{y}.\n",
|
||||
"$$"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"Inserting the above values we obtain that"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"$$\n",
|
||||
"\\hat{\\boldsymbol{\\beta}}=\\begin{matrix}\\frac{11}{5} \\\\ 2\\end{bmatrix},\n",
|
||||
"$$"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"<!-- !split -->\n",
|
||||
"## Linking the regression analysis with a statistical interpretation\n",
|
||||
"\n",
|
||||
|
||||
@@ -429,6 +429,43 @@ We will now couple the discussions of ordinary least squares, Ridge and Lasso re
|
||||
We will amongst other things show that the regularization parameter can reduce considerably the variance of the parameters $\beta$.
|
||||
|
||||
|
||||
!split
|
||||
===== Yet another Example =====
|
||||
|
||||
Let us assume we have a data set with outputs/targets given by the vector
|
||||
|
||||
!bt
|
||||
\[
|
||||
\bm{y}=\begin{matrix}4 \\ 2 \\3\end{bmatrix},
|
||||
\]
|
||||
!et
|
||||
and our inputs as a $3\times 2$ design matrix
|
||||
!bt
|
||||
\[
|
||||
\bm{X}=\begin{matrix}2 & 0\\ 0 & 1 \\ 1 & 0\end{bmatrix},
|
||||
\]
|
||||
!et
|
||||
meaning that we have two features and two unknown parameters $\beta_0$ and $\beta_1$ to be determined either by ordinary least squares, Ridge or Lasso regression.
|
||||
|
||||
!split
|
||||
===== The OLS case =====
|
||||
|
||||
For ordinary least squares (OLS) we know that the optimal solution is
|
||||
|
||||
!bt
|
||||
\[
|
||||
\hat{\bm{\beta}}=\left( \bm{X}^T\bm{X}\right)^{-1}\bm{X}^T\bm{y}.
|
||||
\]
|
||||
!et
|
||||
Inserting the above values we obtain that
|
||||
|
||||
!bt
|
||||
\[
|
||||
\hat{\bm{\beta}}=\begin{matrix}\frac{11}{5} \\ 2\end{bmatrix},
|
||||
\]
|
||||
!et
|
||||
|
||||
|
||||
|
||||
!split
|
||||
===== Linking the regression analysis with a statistical interpretation =====
|
||||
|
||||
Reference in New Issue
Block a user