|
21 | 21 | href="_static/vendor/fontawesome/5.13.0/webfonts/fa-brands-400.woff2"> |
22 | 22 |
|
23 | 23 | <link rel="stylesheet" type="text/css" href="_static/pygments.css" /> |
24 | | - <link rel="stylesheet" href="_static/styles/sphinx-book-theme.css?digest=62ba249389abaaa9ffc34bf36a076bdc1d65ee18" type="text/css" /> |
| 24 | + <link rel="stylesheet" href="_static/styles/sphinx-book-theme.css?digest=5115cc725059bd94278eecd172e13a965bf8f5a9" type="text/css" /> |
25 | 25 | <link rel="stylesheet" type="text/css" href="_static/togglebutton.css" /> |
26 | 26 | <link rel="stylesheet" type="text/css" href="_static/copybutton.css" /> |
27 | 27 | <link rel="stylesheet" type="text/css" href="_static/mystnb.css" /> |
|
37 | 37 | <script src="_static/doctools.js"></script> |
38 | 38 | <script src="_static/clipboard.min.js"></script> |
39 | 39 | <script src="_static/copybutton.js"></script> |
40 | | - <script src="_static/scripts/sphinx-book-theme.js?digest=f31d14ad54b65d19161ba51d4ffff3a77ae00456"></script> |
| 40 | + <script src="_static/scripts/sphinx-book-theme.js?digest=9c920249402e914e316237a7dbc6769907cce411"></script> |
41 | 41 | <script>let toggleHintShow = 'Click to show';</script> |
42 | 42 | <script>let toggleHintHide = 'Click to hide';</script> |
43 | 43 | <script>let toggleOpenOnPrint = 'true';</script> |
@@ -857,7 +857,7 @@ <h2>Confidence Intervals<a class="headerlink" href="#confidence-intervals" title |
857 | 857 | </div> |
858 | 858 | </div> |
859 | 859 | <p>Of course, we don’t need to restrict ourselves to the 95% confidence interval. We could generate the 99% interval by finding what we need to multiply the standard deviation by so the interval contains 99% of the mass of a normal distribution.</p> |
860 | | -<p>The function <code class="docutils literal notranslate"><span class="pre">ppf</span></code> in python gives us the inverse of the CDF. Instead of multiplying the standard error by 2 like we did to find the 95% CI, we will multiply it by <code class="docutils literal notranslate"><span class="pre">z</span></code>, which will result in the 99% CI. So, <code class="docutils literal notranslate"><span class="pre">ppf(0.5)</span></code> will return 0.0, saying that 50% of the mass of the standard normal distribution is below 0.0. By the same token, if we plug 99.5%, we will have the value <code class="docutils literal notranslate"><span class="pre">z</span></code>, such that 99.5% of the distribution mass falls below this value. In other words, 0.05% of the mass falls above this value.</p> |
| 860 | +<p>The function <code class="docutils literal notranslate"><span class="pre">ppf</span></code> in python gives us the inverse of the CDF. Instead of multiplying the standard error by 2 like we did to find the 95% CI, we will multiply it by <code class="docutils literal notranslate"><span class="pre">z</span></code>, which will result in the 99% CI. So, <code class="docutils literal notranslate"><span class="pre">ppf(0.5)</span></code> will return 0.0, saying that 50% of the mass of the standard normal distribution is below 0.0. By the same token, if we plug 99.5%, we will have the value <code class="docutils literal notranslate"><span class="pre">z</span></code>, such that 99.5% of the distribution mass falls below this value. In other words, 0.5% of the mass falls above this value.</p> |
861 | 861 | <div class="cell docutils container"> |
862 | 862 | <div class="cell_input docutils container"> |
863 | 863 | <div class="highlight-ipython3 notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">scipy</span> <span class="kn">import</span> <span class="n">stats</span> |
@@ -984,7 +984,7 @@ <h2>Hypothesis Testing<a class="headerlink" href="#hypothesis-testing" title="Pe |
984 | 984 | <img alt="_images/03-Stats-Review-The-Most-Dangerous-Equation_23_0.png" src="_images/03-Stats-Review-The-Most-Dangerous-Equation_23_0.png" /> |
985 | 985 | </div> |
986 | 986 | </div> |
987 | | -<p>With this at hand, we can say that we are 95% confident that the true difference between the online and face-to-face groups falls between -8.37 and -1.44. We can also construct a <strong>z statistic</strong> by dividing the difference in mean by the $SE\$ of the differences.</p> |
| 987 | +<p>With this at hand, we can say that we are 95% confident that the true difference between the online and face-to-face groups falls between -8.37 and -1.44. We can also construct a <strong>z statistic</strong> by dividing the difference in mean by the <span class="math notranslate nohighlight">\(SE\)</span> of the differences.</p> |
988 | 988 | <p><span class="math notranslate nohighlight">\( |
989 | 989 | z = \dfrac{\mu_{diff} - H_{0}}{SE_{diff}} = \dfrac{(\mu_1 - \mu_2) - H_{0}}{\sqrt{\sigma_1^2/n_1 + \sigma_2^2/n_2}} |
990 | 990 | \)</span></p> |
|
0 commit comments