<p style="text-align:justify"><span style="font-size:14px"><strong>Example 1.1.</strong></span></p>

<p style="margin-left:-2px; text-align:justify"><span style="font-size:14px"><span style="color:black">Determine what the population, sample, parameter, statistic, variable, and data referred to in the following study.</span></span></p>

<p style="margin-left:-2px; text-align:justify">&nbsp;</p>

<p style="margin-left:-2px; text-align:justify"><span style="font-size:14px"><span style="color:black">We want to know the mean amount of extracurricular activities in which high school students participate. We randomly surveyed 100 high school students. Three of those students were in 2, 5, and 7 extracurricular activities, respectively.</span></span></p>

<p style="margin-left:-2px; text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px"><strong>Solution 1.1</strong></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="margin-left:-2px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">population </span></strong><span style="color:black">is all high school students.</span></span></p>

<p style="margin-left:-2px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">sample </span></strong><span style="color:black">is the 100 high school students interviewed.</span></span></p>

<p style="margin-left:-2px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">parameter </span></strong><span style="color:black">is the mean amount of extracurricular activities in which all high school students participate.</span></span></p>

<p style="margin-left:-2px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">statistic </span></strong><span style="color:black">is the mean amount of extracurricular activities in which the sample of high school students&nbsp;participate.</span></span></p>

<p style="margin-left:-2px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">variable </span></strong><span style="color:black">could be the amount of extracurricular activities by one high school student. Let </span><em><span style="color:black">X </span></em><span style="color:black">= the amount of&nbsp;extracurricular activities by one high school student. </span></span></p>

<p style="text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">data </span></strong><span style="color:black">are the number.</span></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px"><strong>Example 1.2</strong></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px">Determine what the key terms refer to in the following study.</span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px">A study was conducted at a local high school to analyze the average cumulative GPAs of students who graduated</span></p>

<p style="text-align:justify"><span style="font-size:14px">last year. </span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px"><strong>Fill in the letter of the phrase that best describes each of the items below.</strong></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px">1. Population ____ 2. Statistic ____ 3. Parameter ____ 4. Sample ____ 5. Variable ____ 6. Data ____</span></p>

<p style="text-align:justify"><span style="font-size:14px">a) all students who attended the high school last year</span></p>

<p style="text-align:justify"><span style="font-size:14px">b) the cumulative GPA of one student who graduated from the high school last year</span></p>

<p style="text-align:justify"><span style="font-size:14px">c) 3.65, 2.80, 1.50, 3.90</span></p>

<p style="text-align:justify"><span style="font-size:14px">d) a group of students who graduated from the high school last year, randomly selected</span></p>

<p style="text-align:justify"><span style="font-size:14px">e) the average cumulative GPA of students who graduated from the high school last year</span></p>

<p style="text-align:justify"><span style="font-size:14px">f) all students who graduated from the high school last year</span></p>

<p style="margin-left:-2px; text-align:justify"><span style="font-size:14px">g) the average cumulative GPA of students in the study who graduated from the high school last year</span></p>

<p style="margin-left:-2px; text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px"><strong>Solution 1.2</strong></span></p>

<p style="text-align:justify"><span style="font-size:14px"><span style="color:black">1. f; 2. g; 3. e; 4. d; 5. b; 6. C</span></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px"><strong>Example 1.3</strong></span></p>

<p style="margin-left:11px; text-align:justify"><span style="font-size:14px"><span style="color:black">Determine what the population, sample, parameter, statistic, variable, and data referred to in the following study.</span></span></p>

<p style="margin-left:11px; text-align:justify"><span style="font-size:14px"><span style="color:black">As part of a study designed to test the safety of automobiles, the National Transportation Safety Board collected and reviewed data about the effects of an automobile crash on test dummies. Here is the criterion they used.</span></span></p>

<p style="margin-left:11px; text-align:justify">&nbsp;</p>

<table cellspacing="0" class="MsoTableGrid" style="border-collapse:collapse; border:none; height:200px; margin-left:88px; width:1000px">
	<caption>
	<p><span style="font-size:18px"><strong>Table 1.1</strong></span></p>
	</caption>
	<tbody>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:1px solid black; height:16px; vertical-align:top; width:195px">
			<div style="text-align:center"><span style="font-size:18px"><strong><span style="color:black">Speed at which Cars Crashed</span></strong></span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:1px solid black; height:16px; vertical-align:top; width:243px">
			<div style="text-align:center"><span style="font-size:18px"><strong><span style="color:black">Location of </span><em><span style="color:black">Driver </span></em><span style="color:black">(i.e., dummies)</span></strong></span></div>
			</td>
		</tr>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:none; height:11px; vertical-align:top; width:195px">
			<div style="text-align:center"><span style="font-size:18px"><span style="color:black">35 miles/hour</span></span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; height:11px; vertical-align:top; width:243px">
			<div style="text-align:center"><span style="font-size:18px"><span style="color:black">Front seat</span></span></div>
			</td>
		</tr>
	</tbody>
</table>

<p style="margin-left:11px; text-align:justify"><span style="font-size:14px"><strong><span style="color:#26397f">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</span></strong></span></p>

<p style="margin-left:11px; text-align:justify"><span style="font-size:14px"><span style="color:black">Cars with dummies in the front seats were crashed into a wall at a speed of 35 miles per hour. We want to know the proportion of dummies in the driver&rsquo;s seat that would have had head injuries, if they had been actual drivers. We start with a simple random sample of 75 cars.</span></span></p>

<p style="margin-left:11px; text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px"><strong>Solution 1.3</strong></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="margin-left:11px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">population </span></strong><span style="color:black">is all cars containing dummies in the front seat.</span></span></p>

<p style="margin-left:11px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">sample </span></strong><span style="color:black">is the 75 cars, selected by a simple random sample.</span></span></p>

<p style="margin-left:11px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">parameter </span></strong><span style="color:black">is the proportion of driver dummies&mdash;if they had been real people&mdash;who would have suffered head injuries in the population.</span></span></p>

<p style="margin-left:11px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">statistic </span></strong><span style="color:black">is proportion of driver dummies&mdash;if they had been real people&mdash;who would have suffered head injuries in the sample.</span></span></p>

<p style="margin-left:11px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">variable </span></strong><em><span style="color:black">X </span></em><span style="color:black">= the number of driver dummies&mdash;if they had been real people&mdash;who would have suffered head injuries.</span></span></p>

<p style="text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">data </span></strong><span style="color:black">are either: yes, had head injury, or no, did not.</span></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px"><strong>Example 1.4</strong></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="margin-left:10px; text-align:justify"><span style="font-size:14px"><span style="color:black">Determine what the population, sample, parameter, statistic, variable, and data referred to in the following study.</span></span></p>

<p style="margin-left:10px; text-align:justify">&nbsp;</p>

<p style="margin-left:10px; text-align:justify"><span style="font-size:14px"><span style="color:black">An insurance company would like to determine the proportion of all medical doctors who have been involved in one or more malpractice lawsuits. The company selects 500 doctors at random from a professional directory and determines the number in the sample who have been involved in a malpractice lawsuit.</span></span></p>

<p style="margin-left:10px; text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px"><strong>Solution 1.4</strong></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="margin-left:10px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">population </span></strong><span style="color:black">is all medical doctors listed in the professional directory.</span></span></p>

<p style="margin-left:10px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">parameter </span></strong><span style="color:black">is the proportion of medical doctors who have been involved in one or more malpractice suits in&nbsp;the population.</span></span></p>

<p style="margin-left:10px; text-align:justify">&nbsp;</p>

<p style="margin-left:10px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">sample </span></strong><span style="color:black">is the 500 doctors selected at random from the professional directory.</span></span></p>

<p style="margin-left:10px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">statistic </span></strong><span style="color:black">is the proportion of medical doctors who have been involved in one or more malpractice suits in the&nbsp;sample.</span></span></p>

<p style="margin-left:9px; text-align:justify"><span style="font-size:14px"><span style="color:black">The </span><strong><span style="color:black">variable </span></strong><em><span style="color:black">X </span></em><span style="color:black">= the number of medical doctors who have been involved in one or more malpractice suits.</span></span></p>

<p style="margin-left:9px; text-align:justify"><span style="font-size:14px">&nbsp;The <strong>data </strong>are either: yes, was involved in one or more malpractice lawsuits; or no, was not.</span></p>