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<table width="100%" summary="page for d.single.t.t"><tr><td>d.single.t.t</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>d for Single t from t</h2>

<h3>Description</h3>

<p>This function displays d and non-central confidence interval for single t
estimated from the t-statistic.
</p>


<h3>Usage</h3>

<pre>
d.single.t.t(t, n, a = 0.05)
</pre>


<h3>Arguments</h3>

<table summary="R argblock">
<tr valign="top"><td><code>t</code></td>
<td>
<p>t-test value</p>
</td></tr>
<tr valign="top"><td><code>n</code></td>
<td>
<p>sample size</p>
</td></tr>
<tr valign="top"><td><code>a</code></td>
<td>
<p>significance level</p>
</td></tr>
</table>


<h3>Details</h3>

<p>To calculate d, the t-statistic is divided by the square root of the sample size.
</p>
<p>d = t / sqrt(n)
</p>
<p><a href="https://www.aggieerin.com/shiny-server/tests/singlett.html">Learn more on our example page.</a>
</p>


<h3>Value</h3>

<p>The effect size (Cohen's d) with associated confidence intervals
and relevant statistics.
</p>
<table summary="R valueblock">
<tr valign="top"><td><code>d</code></td>
<td>
<p>effect size</p>
</td></tr>
<tr valign="top"><td><code>dlow</code></td>
<td>
<p>lower level confidence interval d value</p>
</td></tr>
<tr valign="top"><td><code>dhigh</code></td>
<td>
<p>upper level confidence interval d value</p>
</td></tr>
<tr valign="top"><td><code>n</code></td>
<td>
<p>sample size</p>
</td></tr>
<tr valign="top"><td><code>df</code></td>
<td>
<p>degrees of freedom (sample size - 1)</p>
</td></tr>
<tr valign="top"><td><code>t</code></td>
<td>
<p>sig stats</p>
</td></tr>
<tr valign="top"><td><code>p</code></td>
<td>
<p>p-value</p>
</td></tr>
<tr valign="top"><td><code>estimate</code></td>
<td>
<p>the d statistic and confidence interval in
APA style for markdown printing</p>
</td></tr>
<tr valign="top"><td><code>statistic</code></td>
<td>
<p>the t-statistic in APA style for markdown printing</p>
</td></tr>
</table>


<h3>Examples</h3>

<pre>

#A school has a gifted/honors program that they claim is
#significantly better than others in the country. The gifted/honors
#students in this school scored an average of 1370 on the SAT,
#with a standard deviation of 112.7, while the national average
#for gifted programs is a SAT score of 1080.

    gift = t.test(singt_data, mu = 1080, alternative = "two.sided")

#According to a single-sample t-test, the scores of the students
#from the program were significantly higher than the national
#average, t(14) = 9.97, p &lt; .001.

#You can type in the numbers directly as shown below, or refer
#to your dataset within the function.

    d.single.t.t(t = 9.968, n = 15, a = .05)

    d.single.t.t(9.968, 15, .05)

    d.single.t.t(gift$statistic, length(singt_data$SATscore), .05)
</pre>


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