EnvironMentors Data Analysis 101
“Facts are the air of scientists. Without them you can never fly”
Essentials of Data Capture and Analysis
Careful Collection
~ Linus Pauling
Index
What would the world look like if nobody bothered to be systematic in their science experiments? Would we trust the food we eat, cars we drive, or pharmaceutical drugs we rely on? Chances are, no. That’s because scientific data is only as trustworthy and reliable as the scientist who collected it and the methods they used. The more accurate and consistent the data collection, and the more data collected, the more we can trust its findings. Accurate and consistent methods permit experiments to be repeated, to gather further results for comparison.
Careful Collection
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Accurate Analysis
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Practice Makes Perfect
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Sharing Strengths
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Additional Resources
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Keys to Good Data Collection •
Draft data collection tables before collecting
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Identify and map the exact sampling location
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Be consistent: take at least 3 data collection trials, exactly the same each trial
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Be accurate: use tools that are clean, calibrated, and working correctly
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Record sampling location, date, time, and other potential variables (e.g., weather)
Remember—there are resources in the
Accurate Analysis Some basic math (dare we say statistical) skills are at the core of any data analysis. Helping students understand concepts like mean, median, and mode will go a long way. Other statistics that might be useful to students include range, standard deviation, and margin of error.
Having high quality, well-analyzed data isn’t enough. Students must be able to properly display data. This means understanding how to graph data using bar, line, and pie graphs, and knowing what information each conveys. In addition, these displays must always include a title and labeled units.
Coordinator-Teacher Manual’s Data Collection and Analysis section, page 222.
EnvironMentors Data Analysis 101
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Key Concepts in Student Data Analysis Statistics Mean: the average Median: the central value of an ordinal distribution Mode: most frequent value in your data set Graphs Bar graph: show relationships between groups Line graph: show how changes in one variable affect changes in another, or changes over time Pie graph: show how part of something relates to the whole, like percentages
Practice Makes Perfect One of the best ways to help your students master and become comfortable doing data collection and analysis is by doing it with them. By gathering and analyzing sample data as a class you can:
Transportation method
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Demonstrate good data collection techniques;
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Collect data to be analyzed as a class/group; and
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Review key mathematical and graphical concepts.
Freshmen
Sophomores
Some simple data you may be able to collect within walking distance of your school include: recycling bins versus trash bins in classrooms; animals and plants in a nearby greenspace; or commuting methods to school among students. Decide what questions you want to ask as a group – tailor it to student interests or something you’ve recently talked about in class. Together, discuss how and where to collect your data. What is your sample size? Your observation sites? This will depend on your logistical constraints. Juniors
Seniors
By Car By Bus By Bike On foot Other
After making your observations, come together as a class and compare your findings by filling in the data collection chart. What are some trends you see? What questions can the data not answer? What other factors does this observation not take into account? (time of day, time of year, etc). What type of information would a bar graph demonstrate? A Line or pie graph?
EnvironMentors Data Analysis 101 Sharing Strengths One way to lighten your work load while providing additional support to your students is to partner with a math teacher at your school. Your mathematics teachers will understand how best to teach students analysis and graphing concepts, and may be excited to partner with you.
With your colleague, determine the best venue for reviewing these concepts. It may be during class time, or after schools. S/he may be able to work with EnvironMentors students and their data on an individual basis, or as a group. If you’ve collected some sample activity as a class, share it with your colleague. It will give them meaningful data to build upon if students do not have individual project data yet.
Additional Resources Bottled versus Tap Water Design and run an experiment with your students testing whether they prefer the taste of bottled or tap water. This lesson plan can be adapted to include measuring other variables besides taste, such as color and odor. Introduces the importance of regulating water safety and differences in bottled and tap water regulations. http://www.caryinstitute.com/education/curriculum/bottled-vs-tap-water Understanding Tides and Sea Level Using Real Data Investigate variations and fluctuations in the ocean’s tides through these activities, using real data. These lesson plans can be adapted to design your own investigation on tides – compare changes over time in one location, or global differences in tides. Includes a teacher’s guide and links to online tidal data sources. Similar studies can be done using temperature, humidity, and precipitation records. http://www.dataintheclassroom.org/content/sea-level/teachers.html Is There Biodiversity in Our Backyard? Explore biodiversity in your school grounds. This link provides an overview of the activity and a link to a pdf. This lesson can be adapted to include species identification, development of a “schoolyard species guide” or student writing/sketching/photographic observations. http://www.amnh.org/education/resources/card_index.php?rid=177&standardDetail=1 Measurement and Variation in Objects Use any common object – pencils, peanuts, rocks, shells, chalk – to practice data collection and analysis, and help students understand the importance of precise data collection. Explores human sampling error as well as margin of error due to different sampling devices (ruler vs. calipers). Emphasizes analysis of data using mean, median, mode, and range. http://www.ciblearning.org/resource.exercise.measurement.php
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