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  <name>Confidence Intervals: Confidence Interval Lab II (edited: Teegarden)</name>
  <metadata>
  <md:version>1.1</md:version>
  <md:created>2008/08/12 15:46:42.543 GMT-5</md:created>
  <md:revised>2008/08/12 15:47:45.749 GMT-5</md:revised>
  <md:authorlist>
      <md:author id="tteegard">
      <md:firstname>Mary</md:firstname>
      <md:othername>T</md:othername>
      <md:surname>Teegarden</md:surname>
      <md:email>tteegard@sdccd.edu</md:email>
    </md:author>
  </md:authorlist>

  <md:maintainerlist>
    <md:maintainer id="tteegard">
      <md:firstname>Mary</md:firstname>
      <md:othername>T</md:othername>
      <md:surname>Teegarden</md:surname>
      <md:email>tteegard@sdccd.edu</md:email>
    </md:maintainer>
  </md:maintainerlist>
  
  <md:keywordlist>
    <md:keyword>elementary</md:keyword>
    <md:keyword>statistics</md:keyword>
  </md:keywordlist>

  <md:abstract>Labs changed to incorporate mini-tabs.</md:abstract>
</metadata>
  <content>
    <para id="id6317858">Class Time: </para>
    <para id="id6317864">Name:</para>
    <section id="id-500604764518">
      <name>Student Learning Outcomes: </name>
      <list type="bulleted" id="id6317875">
        <item>The student will calculate the 90% confidence interval for proportion of students in this school that were born in this state.</item>
        <item>The student will interpret confidence intervals.</item>
        <item>The student will examine the effects that changing conditions has on the confidence interval.</item>
      </list>
    </section>
    <section id="element-614"><name>Collect the Data</name><list id="list-8758234" type="enumerated"><item>Survey the students in your class, asking them if they were born in this state. Let 
<m:math><m:semantics><m:mrow><m:mstyle fontsize="12pt"><m:mrow><m:mi>X</m:mi></m:mrow></m:mstyle><m:mrow/></m:mrow><m:annotation encoding="StarMath 5.0"> size 12{X} {}</m:annotation></m:semantics></m:math> = the number that were born in this state.<list id="list986y" type="named-item"><?mark .?>
			<item><name>a</name><m:math><m:semantics><m:mrow><m:mstyle fontsize="12pt"><m:mrow><m:mi>n</m:mi></m:mrow></m:mstyle><m:mrow/></m:mrow><m:annotation encoding="StarMath 5.0"> size 12{n} {}</m:annotation></m:semantics></m:math> =<m:math><m:mtext>____________</m:mtext></m:math></item>
			<item><name>b</name><m:math><m:semantics><m:mrow><m:mstyle fontsize="12pt"><m:mrow><m:mi>x</m:mi></m:mrow></m:mstyle><m:mrow/></m:mrow><m:annotation encoding="StarMath 5.0"> size 12{x} {}</m:annotation></m:semantics></m:math> =<m:math><m:mtext>____________</m:mtext></m:math>
			</item>
		</list>
	</item>
	<item>Define the Random Variable 
<m:math><m:semantics><m:mrow><m:mstyle fontsize="12pt"><m:mrow><m:mrow><m:mi>P</m:mi><m:mi>'</m:mi></m:mrow></m:mrow></m:mstyle><m:mrow/></m:mrow><m:annotation encoding="StarMath 5.0"> size 12{P'} {}</m:annotation></m:semantics></m:math> in words. </item>
	<item>State the estimated distribution to use. </item>
</list></section><section id="element-373"><name>Find the Confidence Interval and Error Bound</name><list id="list-9758575342" type="enumerated"><item>Calculate the confidence interval and the error bound.
<list id="list-858645876" type="named-item"><?mark .?>
			<item><name>a</name>
Confidence Interval:</item>
			<item><name>b</name>Error Bound:</item>
		</list>
	</item>
	<item> How much area is in both tails (combined)? <m:math><m:mi>α</m:mi></m:math>=</item>
	<item>How much area is in each tail?
<m:math>
			<m:mfrac>
				<m:mi>α</m:mi>
				<m:mn>2</m:mn>
			</m:mfrac>
		</m:math>
=</item>
	<item>Fill in the blanks on the graph with the area in each section. Then, fill in the number
line with the upper and lower limits of the confidence interval and the sample proportion.
<figure><media type="image/png" src="wave1.PNG">
	<param name="alt" value="Normal distribution curve with two vertical upward lines from the x-axis to the curve. The confidence interval is between these two lines. The residual areas are on either side."/>

	<param name="print-width" value="3in"/>
</media></figure></item>
<item>How large a sample would be needed to ensure that the error for the 90% confidence interval is only 5%?  Use the previous data as an estimate for p.</item>
<item>Recalculate the sample size assuming there is no previous data.</item></list></section><section id="element-850"><name>Describe the Confidence Interval</name><list id="list-97584" type="enumerated"><item>In two to three complete sentences, explain what a Confidence Interval means (in general), as
if you were talking to someone who has not taken statistics.</item>
	<item>In one to two complete sentences, explain what this Confidence Interval means for this
particular study.</item>
	<item> Using the above information, construct a confidence interval for each given confidence
level given.
<table id="id6699poi200">
<?table-summary Partially blank table with confidence level in the first column, EBM/Error Bound in the blank second column, and confidence interval in the blank third column.?>
			<tgroup cols="3"><colspec colnum="1" colname="c1"/>
				<colspec colnum="2" colname="c2"/>
				<colspec colnum="3" colname="c3"/>
				<thead>
					<row>
						<entry>Confidence level</entry>
						<entry>EBP / Error Bound</entry>
						<entry>Confidence Interval</entry>
					</row>
				</thead>
				<tbody>
					<row>
						<entry align="center">50%</entry>
						<entry/>
						<entry/>
					</row>
					<row>
						<entry align="center">80%</entry>
						<entry/>
						<entry/>
					</row>
					<row>
						<entry align="center">95%</entry>
						<entry/>
						<entry/>
					</row>
					<row>
						<entry align="center">99%</entry>
						<entry/>
						<entry/>
					</row>
				</tbody>
			</tgroup>
		</table></item>
	<item>What happens to the EBP as the confidence level increases? Does the width of the
confidence interval increase or decrease? Explain why this happens.</item></list></section>
  </content>
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