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	OVERVIEW</p>
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	Students have collected data and created graphs, charts, illustrations, or tables summarizing their results. This is the evidence that will support or refute their project hypothesis. Now is the time to look at that evidence and figure out what it means. The outcomes of this activity can be simple: a statement addressing whether or not the hypothesis was supported, and a few statements or bullet points discussing why or why not. More generally an outcome is an increased understanding by students that <b>the data are the facts, and interpreting data is where some judgment calls come in. </b>It is important for students to go through the whole process, from dealing with those facts to making the calls.</p>
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<h2>
	<a name="TOC-GETTING-READY"></a>GETTING READY</h2>
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	Begin by writing the hypothesis (or hypotheses, if groups had variations on the theme) on the board or overhead.<br />
	Be sure each group or the class has copies of their data products (graphs, etc.) in front of them.</p>
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	<h2>
		<a name="TOC-ACTIVITY-PROCEDURE"></a>ACTIVITY PROCEDURE</h2>
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		This activity is a thinking exercise. It can be done in a number of ways: a group discussion session, setting up students in debate teams to argue the evidence one way or another; or any number of other ways that facilitates discussion and ends with a general consensus.</p>
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		One of the key skills in interpreting what data mean is to understand how to read a graph. Model for the students how to explain a graph or table. For example, for the following graph a description would go something like:</p>
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		<span><a href="https://sites.google.com/site/mercuryourwatershedfriends/watershed-experiences/unit-5/c-what-does-it-mean/ActC.jpg?attredirects=0" imageanchor="1"><img border="0" height="290" src="https://sites.google.com/site/mercuryourwatershedfriends/_/rsrc/1290110391395/watershed-experiences/unit-5/c-what-does-it-mean/ActC.jpg?height=290&amp;width=320" width="320" /></a></span></div>
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		<i>&ldquo;This graph shows fish weight in kilograms on the X axis, and the concentration of mercury in fish muscle in nanograms per gram on the Y axis. Each dot represents a fish. As fish weight increased, muscle mercury increased. This positive relationship is shown with a regression line &ndash; the diagonal line on the graph. The R-squared value tells us how good the relationship is. This R-squared is pretty good &ndash; 0.7.&rdquo;</i></p>
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		<b><i>Then end with the take home message of the graph in plainer English: </i></b><i>&ldquo;So this graph says that as fish got bigger, they had more mercury in their muscles.&rdquo;</i></p>
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		First, elect a student to act as the class recorder, writing thoughts on the board. Read aloud, or have a student read aloud, the hypothesis. Then have each group show its data product and explain what is shown.<span>&nbsp; </span>Make sure they describe what is on each axis or in each column, list the units displayed, and end with the important plain English sentence saying what it means. If you can say what a data product&rsquo;s message is in plain English you&rsquo;ve got the finding internalized and not memorized. Have the recording student write down, in words, the description of the graph or table &ndash; these words will become the legend for the figure when you&rsquo;re presenting results in Unit 6.</p>
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		Now ask students to make a judgment whether their hypothesis was supported or not supported based on the data they&rsquo;ve been shown. This can be done with a show of hands, a vote, or a discussion. Emphasize that there is a bit of &lsquo;best professional judgment&rsquo; involved &ndash; scientists can only base their findings on the evidence, and often the evidence is incomplete or we wish we&rsquo;d sampled some additional variable. This is why science is sometimes perceived as frequently changing or tentative.</p>
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		Finally, have students discuss why they think the hypothesis was supported or not. Here is a list of leading questions to use if needed:</p>
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		Have the students coordinate and edit their thoughts down into the following:</p>
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			Statement of whether hypothesis was supported or not. &ldquo;Our hypothesis that X would be greater than Y was/was not supported by the data.&rdquo;</li>
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			Bullet points interpreting the findings:</li>
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		<b>a. </b>What the data showed: &ldquo;In fact, mercury in Y was greater than mercury in X, as shown in Figure 1.&rdquo;<br />
		<b>b. </b>Thoughts why the hypothesis was or was not supported: &ldquo;We were only able to catch big fish of one species, so we could not determine whether size or species was more important. Also, all of the biggest fish were caught in Pond B, so we could not compare within a single pond&rdquo;.<br />
		<b>c. </b>What would they do differently next time: &ldquo;In the future students should consider only sampling in Pond B, and only sampling one species to remove the confounding effects of species and ponds&rdquo;.</div>
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		&nbsp;<b>** Be sure to keep a hard copy or electronic version of the figures, tables, diagrams, legends, and bullet points. You will use these in <a href="https://sites.google.com/site/mercuryourwatershedfriends/watershed-experiences/unit-6">Unit 6</a>. **</b></p>
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	<h2>
		<a name="TOC-ASSESSMENT-IDEAS"></a>ASSESSMENT IDEAS</h2>
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		Students need to be able to create graphs to help tell their research stories. More importantly, in the class and in everyday life, students need to be conscious consumers of information in a graphic form. By peer reviewing other students&rsquo; graphs the students practice interpreting graphs, and graph creators receive feedback to improve or clarify the story that they are trying to tell.</p>
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		Each student should review at least two graphs generated by other students and provide feedback. The feedback that these students receive in turn should be used to improve or clarify their own graphs. Students are assessing the work of each other and in turn being assessed on their ability to be discriminating consumers of graphic information.</p>
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		<a href="https://docs.google.com/viewer?a=v&amp;pid=sites&amp;srcid=ZGVmYXVsdGRvbWFpbnxtZXJjdXJ5b3Vyd2F0ZXJzaGVkZnJpZW5kc3xneDoxODRiNDNkMDZlYzk2ZWNh" target="_blank">Here is a worksheet of instructions</a> that can be handed out to students.</p>
	<h2>
		<a name="TOC-EXTENSION"></a>EXTENSION</h2>
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		<a href="https://sites.google.com/site/mercuryourwatershedfriends/watershed-experiences/unit-5/c-what-does-it-mean/ActC_X.jpg?attredirects=0" imageanchor="1" target="_blank"><img border="0" height="395" src="https://sites.google.com/site/mercuryourwatershedfriends/_/rsrc/1290111116008/watershed-experiences/unit-5/c-what-does-it-mean/ActC_X.jpg?height=395&amp;width=400" width="400" /></a></div>
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		The skills used in this unit can help students interpret and understand the limitations of graphs and data. Using newspapers, magazines, or the Internet, have each student or group find several examples of graphs or data presentations in the public media. Have students interpret each graph, either individually or in a group discussion. Ask them whether the graphs show a clear pattern, differences, or a relationship. See if they can locate any &lsquo;fine print&rsquo; or estimates of the error in the data. Based on the data &ndash; the empirical evidence shown in the graphs they&rsquo;ve found &ndash; how much faith do they put in the conclusions of the graph producers?</p>
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		Using the graphs from The New York Times you might ask students questions like:</p>
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			What does each line represent?</li>
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			Do the authors tell you how much variability (spread) there is around each line? The graph makes the pattern look very clear &ndash; but there is probably a lot more noise if you could see all of the data.</li>
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			Do you think there&rsquo;s more variability in the men than the women? How could you tell?</li>
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			How would you know if there were real differences among time periods?</li>
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			If you only looked at the &ldquo;both sexes&rdquo; graph, what would you think the average life expectancy was for someone who was most deprived? And how much difference does it make to separate the genders?</li>
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	<h2>
		<a name="TOC-DOCUMENTS"></a>DOCUMENTS</h2>
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		These documents can be viewed by clicking the links below.&nbsp; Individual PDFs of each document can be downloaded from the &quot;Attachments&quot; at the bottom of this web page.</p>
	<h3>
		<a name="TOC-Handouts"></a>Handouts</h3>
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			<a href="https://docs.google.com/viewer?a=v&amp;pid=sites&amp;srcid=ZGVmYXVsdGRvbWFpbnxtZXJjdXJ5b3Vyd2F0ZXJzaGVkZnJpZW5kc3xneDoxODRiNDNkMDZlYzk2ZWNh" target="_blank">For the assessment - student instructions</a></li>
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