Understanding Experimental Design LAB –

Understanding Experimental Design LAB –

OVERVIEW

Scientists conduct experiments in order to understand how the natural world works. Virtually all of the science you learn in this and your other science classes was discovered and verified by repeated experiments. Designing and running a good experiment is challenging, time-consuming, and expensive. What makes experiments worthwhile, indeed critical, is that they are the most powerful tool we have for establishing cause-and-effect relationships. Educated citizens need to understand how scientific investigations are done and how results and conclusions are reported in order to make informed decisions. This lab will introduce you to the principles of good experimental design. Because these principles are best learned by carrying out an actual experiment, your challenge will be to design, conduct, and interpret your own experiment.

BE ORIGINAL! Remember to use your own words and do not copy verbatim from any online, previous or current student source. By submitting this assignment, you are agreeing to the following statement: “I understand that my paper will be checked against multiple sources for original content. A report will be generated that shows if content in this paper matches content in documents available on the Internet, in many print journals, and a database of other papers submitted by students. If submitted to the instructor, my paper will be added to the student database for comparison of future OSU papers against it. I maintain ownership of the original intellectual property created in this paper. I understand that results of this report may be used by the University in student conduct proceedings related to academic dishonesty (See Canvas Start Here module for more information)” Turnitin generates a report that highlights any potentially unoriginal text in your paper, including text from previous students’ or current students’ submissions.

ASSIGNMENT

Section 1 Reflection (2 pts)

Take the opportunity to reflect back on last week’s work. Please use complete sentences!

a) Identify one thing you did well. Be specific and use an example.

I had less driving time last week, and more time I chose to carpool or use public transportation, and in China we use a software called Didi to complete carpool trips, which not only cut down on travel costs. It can also effectively reduce carbon emissions per capita.

b) Identify one thing you could improve upon. Be specific and use an example.

I think instead of taking public transport or carpooling, I should choose to walk or ride a bike, so I can exercise on the one hand, and reduce individual carbon emissions on the other. In many cities in China, we have public bike for just $1 a month and you can ride unlimited times, and you can find it anywhere at any time and also same as park it.

c) Find and copy a grader’s comment on your work here. Not sure where to look? See the ‘submission comments’ on your assignment, or email and ask!

Type answer here

d) Respond to the grader (Who will read this! This is your opportunity to connect!). You could state how you could have done better, did you need to double check a value, ask a question, look something up, put something in your own words?

Type answer here

Section 2 What Makes a Good Experiment (5 pts)

Section 1 of the lab is an interactive tutorial that introduces the components of a good experiment. Section 1 warms you up with 17 low-stakes, coached questions. This section will be completed entirely within SimUText and you will get credit simply for completing it.

Note, you must get these questions correct to get credit! This means clicking through AND correcting your mistakes when prompted by the program. This section is meant to prime you for creating your own experiments in Section 2!

Section 3 Part 1: Save the Simploids! (10 pts)

Section 2 of the lab helps you practice in SimUText and receive feedback as you design experiments, generate quality scientific data, and state conclusions of what is sickening the Simploids. I have provided a table in this document for you to keep track of your experiments and results for your summary report in Section 2 Part 2. 10 pts for answering the questions in SimUText AND completing the tables.

· Work through the warmup questions Q2.1-Q2.3. Then select a hypothesis to test with your first experiment.

· Design and carry out a minimum of TWO experiments to address the problem of the sick Simploids. Based the data from each experiment, answer the questions in SimUText, including stating your scientific conclusion of what is causing the Simploids to sicken.

· Fill in the tables below as you work through SimUText experiments (note that the table does not ask exactly the same things as the tutorial – pay careful attention in order to answer correctly). This will help you organize your summary report that you submit in Section 3 of the lab.

Experiment 1

Hypothesis 1. Simploids are sick due to: Parasites or Herbicides
Experiment 1. What is the independent variable? Identify variable
Experiment 1. What is (are) the dependent variable(s)? List variables
Experiment 1. Which variable(s) did you hold constant across all experimental groups (which may be confounding variables)? List variables
Experiment 1. How many replicates did you have of each combination of variables? Number
Experiment 1. What do you conclude? Was Hypothesis 1 supported? Yes or No
Experiment 1. How did your results support your conclusion. Transcribe summary paragraph from SimUText Section 2 Q2.10 Write a summary paragraph from Q2.10 here

Experiment 2

Hypothesis 2. Simploids are sick due to: Parasites or Herbicides
Experiment 2. What is the independent variable? Identify variable
Experiment 2. What is (are) the dependent variable(s)? List variables
Experiment 2. Which variable(s) did you hold constant across all experimental groups (which may be confounding variables)? List variables
Experiment 2. How many replicates did you have of each combination of variables? Number
Experiment 2. What do you conclude? Was Hypothesis 2 supported? Yes or No
Experiment 2. How did your results support your conclusion for Experiment 2. Type answer here

Overall conclusion

Draft explanation to town of Idyllic. Transcribe your explanation from SimUText Section 2 Q2.15. Summarize answer from Q2.15 here

· After conducting each experiment, export ALL the data from that experiment to your computer (see button below!):

Click “Export Data” (see image to the left!) and then save the file (default name is “results.txt”) to your computer. Make sure to give your two results files different names. Open the files in a spreadsheet application and organize the data into data tables. You are encouraged, but not required, to make graphs of key results. Your summary report in Section 3 Part 2 MUST refer to the tables and any graphs submitted.

Helpful Hints: There are descriptions of the data columns in the LAB Background document. The LAB Demonstration video shows how to export data from SimUText and import it to your spreadsheet application. Recall that you learned how to explore, sort, and filter data in the Ecological Footprint lab; those skills will come in handy here as well.

Section 3 Part 2: Report with Data (15 pts)

This section is NOT in the SimUText application, and is REQUIRED. Complete a report for the city of Idyllic that states your conclusion of what is happening to the Simploids, describes the experiments you conducted, and provides supporting data for your conclusion. Look to the tables you completed as you worked through Section 2 to fill in the blanks. We have provided a template report letter for you to fill in.

You must present your data in your lab assignment, by submitting your data table(s) (with ALL OF the data) along with a paragraph explaining how you came to your conclusion based on the data. This section requires the use of a spreadsheet application (Microsoft Excel, Google Sheets, etc.) to construct your tables. Paste your tables, with clear descriptions, into the placeholders below.

Report to the Town of Idyllic (5 pts)

I have provided a template for your report below. If you did more than two experiments, add another paragraph to the methods for each additional experiment.

· Fill in all areas denoted by red brackets, […], to complete a report on your experiments to submit to the town of Idyllic. Wherever you see [red brackets], you need to type an answer. Please keep your answers in RED text!

Dear Town of Idyllic,

My research into the effects of herbicides and parasites on the health of Simploids indicates [type conclusion here]. Based on these results, I recommend you take the following actions to improve and protect the health of Simploids in your community:

[type recommendations here].

I came to this conclusion by conducting the following experiments.

My first experiment tested […] by experimentally changing […] and observing the effects on […]. This experiment demonstrated that […]. This conclusion is supported by the data shown in Table 2.1 below.

My second experiment tested […] by experimentally changing […] and observing the effects on […]. This experiment demonstrated that […]. This conclusion is supported by the data shown in Table 2.2 below.

Taken together, the results of these experiments indicate that [restate conclusion here] is the cause of Simploid sickness in the town of Idyllic.

Table 2.1. Experiment 1 Data Table (5pts)

The data table must be labeled and units clearly indicated. Hint: if there are only a handful of rows or columns in your table, you did something wrong! Go back and review the video to download data from SimUText.

Copy and paste your data table here. (Delete this box)

Description: [Summarize what these data tell you and how you came to your conclusion based on the data.]

Table 2.2 Experiment 2 Data Table (5pts)

The data table must be labeled and units clearly indicated. Hint: if there are only a handful of rows or columns in your table, you did something wrong! Go back and review the video to download data from SimUText.

Copy and paste your data table here. (Delete this box)

Description: [Summarize what these data tell you and how you came to your conclusion based on the data.]

Section 4 Autograded questions (10 pts)

This section includes 10 autograded questions that you will complete in SimUText.

Section 5 Synthesis and Relevance (8 pts)

Each lab we will check-in with the current state of the world and let you know how this week’s lab topic is relevant to you and to sustainability. This portion of the lab may reference a news story, scientific study just published, or a local event.

Monarch butterflies – our own Simploids?

The iconic Monarch butterfly is declining – and it is unclear exactly why. In this lab we learned about how experimental design can help us solve a mystery: What was killing the Simploids? Well, in the real world we might ask: What is killing the Monarch Butterflies?

Think about the experiment you performed above and do some internet searching to answer the following questions:

a) Name three threats that the Simploids faced in the experiment above (hint: we only tested two…but there’s one more! What did you have to add to the plots so Simploids could live?? What did they eat??)

type your answer here

b) Name three threats for Monarch Butterflies that are similar to those for the Simploids. (hint: look at the threats for the Simploids; might these be the same or different for butterflies in the real world? Do a little research if you need to!)

type your answer here

c) Now think about how you determined the biggest threat to the Simploids. How could you test which of the three things you listed above is the primary threat for Monarch Butterflies? Write a couple of sentences at least!

type your answer here

d) What do scientists say is the biggest threat to Monarch Butterflies (hint, what do most folks recommend you can do to HELP Monarchs (again, do a quick internet search!))?

type your answer here

Last modified: June 26th 2018

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