Islands Assessment: Experimental design
Islands Assessment: Experimental design
Due date: Week 13. 1159 PM Friday 24th May 2023 (submit via turnitin)
This assignment is to be completed individually. It is good learning practice to discuss general concepts with other students and work together to improve your understanding of unit content. However, it is NOT acceptable to work closely with other students to complete the actual assignment questions or collaborate on the written presentation of this assignment.
This assessment has been designed to give you the opportunity to practice and learn concepts in a real-life way. These concepts will be essential as you move forward in your academic careers. Make the most of this opportunity by working independently! You will need to apply these concepts in real life, so if you find any aspects of this assignment difficult, it is better to ask for help than to copy from another student.
Academic integrity
students.curtin.edu.au/essentials/rights/academic-integrity/Academic integrity at its core is about honesty and responsibility and is fundamental to Curtins expectations of you. This means that all of your work at Curtin should be your own and it should be underpinned by integrity, which means to act ethically, honestly and with fairness.
As a Curtin student you are part of an academic community and you are asked to uphold the UniversitysCode of Conduct, principles of academic integrity, andCurtins five core valuesof integrity, respect, courage, excellence and impact during your studies.
You arealso expected to uphold theStudent Charterand recognise that cheating, plagiarism collusion, and falsification of data and other forms of academic dishonesty are not acceptable.
Please carefully read the following information regarding appropriately acknowledging your internet resources
Use of internet sources; Generative AI, forums, and online blogs
In this unit you are allowed to use internet sources such as forums (e.g. Stack overflow), blogs and generative AI (e.g. ChatGPT) as a resource to help with your coding and R scripts. Please note however that all the information and code that you need will be provided to you during the unit.
You should not use these sources to help with your written work and interpretation.
Referencing internet sources; Generative AI, forums, and online blogs
If you use a resource other than those provided by us this should be acknowledged in writing. You should include a declaration, in your code, or in an acknowledgements section for a scientific report.
The declaration should be similar to this:
I acknowledge the use of (insert resource name and URL) in the preparation of my code and statistical analysis. I have used (insert resource name) to assist with (specify the steps where the resource has been used).
You should also include a declaration as an annotation within your RScript:
##The following code was produced with assistance from (resource name and URL).
Or
##The following code was modified from an example provided by (resource name and URL)
Please review the library guidelines on referencing:
Referencing generative AI (e.g., ChatGPT)
Updated guidelines have been incorporated into the four referencing guides, following the approach adopted by Curtin for semester one. The guides outline the requirement to use in-text citations (following personal communication reference types) where text has been quoted or paraphrased, and the inclusion of a declaration, detailing how generative AI has been used in the assignment process.
Please carefully read the following information regarding academic misconduct; cheating, collusion, and plagiarism
What is academic misconduct?
Academic misconduct refers to conduct by a student that is dishonest or unfair in connection with any academic work.
Cheating is acting dishonestly or unfairly in order to gain an advantage. Examples include:
Cheating in an exam, test or supervised assessment activity.
Cheating in an assessment or other assessable work:
Submitting written or creative work which has been drafted or produced by someone else including friends, family or a paid contracting service (this is known as contract cheating, assessment outsourcing or ghost writing) and claiming authorship for it. This includes:
Allowing someone or an organisation to draft or complete an assessment task on your behalfContracting another person to do the work for youPurchasing work from another source
Allowing or contracting another person to edit and substantially change your workCollusion is where students act together in relation to the preparation or presentation of any assessed item of work in a manner that is dishonest or unfair. Examples include:
Working with another person (colluding) when the assessment should be completed individually;In the case of collaborative group projects, falsely representing the individual contributions of the collaborating group members.
Plagiarism is knowingly presenting the work or property of another person as your own without appropriate acknowledgement or referencing. It includes:
Copying of sentences, paragraphs or creative products (in whole or in part) which are the work of other persons without due acknowledgment. Creative products include webpages, books, articles, theses, unpublished works, working papers, seminar and conference papers, internal reports, lecture notes or recordings, computer files, images or videoToo closely paraphrasing sentences, paragraphs or themes without due acknowledgment
Using another persons work (including words, music, creative or visual artefacts, computer source code, designs, problem solutions or ideas)
In the case of collaborative group projects, falsely representing the individual contributions of the collaborating partnersSubmitting work which has been produced by someone else including friends, family or a paid contracting service (This is known as contract cheating, assessment outsourcing or ghost writing.)
Submitting ones own previously assessed or published work for assessment or publication elsewhere, without appropriate acknowledgement (self-plagiarism)
Allegations of misconduct are managed in accordance withStatute 10: Student Discipline. Thestudent conduct guidehelps explain the process if you receive an allegation of misconduct.
Refer to https://about.curtin.edu.au/governance/academic-integrity/ and oasis.curtin.edu.au/ConductAtCurtin/AcademicIntegrity for more information, including student guidelines for avoiding plagiarism.
This assignment will be fully introduced during the computer Lab classes in week 8.
The experiment
You are an agriculturist working on the Islands. You have been tasked by the island communities to increase crop yields using different fertilisers on the three islands. The fertiliser mix can be changed with regard to how much phosphate and/or nitrogen you add. As well as identifying which fertiliser mix provides the best yield, you also need to determine if the effect of fertiliser is the same across the three islands.
There is a field station on each island which consists of one large field. The field is divided into 6 rows and 6 columns to provide 36 plots for growing plants. You do not need to use all of them. In each plot you can add 0 to 5 levels of nitrogen and/or phosphorus. Once you have set the levels in the field, the plants will start to grow. Seven days in real life represents the length of a season (3 months) in island time. You should allow a growing period of 14 days, or six months/two seasons in island time. Following this you can assess the impact of variable fertiliser treatments by counting the buds, flowers, fruit, or leaves. At the end of your trial you should harvest the plant to provide a yield measurement.
For this task, you have to design a field experiment that determines how fertiliser treatments influence crop performance and determine if these effects are consistent between islands. You need to have a fully developed research question before initiating the simulation. Whilst designing your experiment you will need to consider replication, randomisation, and controls. It is essential that you conduct a-priori power analysis to determine the appropriate number of samples per treatment. You have previously conducted some background research to determine the effect size, and decided that an effect size value of 0.5 is most appropriate.
This assignment assesses the following unit learning outcomes:
Describe, summarise and appropriately present data.
Screen and appropriately transform data.
Select appropriate methods of statistical analysis for data sets and perform these procedures using statistical software.
Interpret and describe the output of statistical analyses in a manner appropriate for a scientific report.
Assignment instruction:
You are to write up your experiment in the format of a scientific paper (less than 3,000 words excluding references and appendix) and should include:
1) a short introduction that leads to the purpose of the experiment, and your HA hypotheses
2) a detailed and concise methods section that also includes a site description
3) a results section with appropriate tables and graphs
4) a discussion with recommendations and conclusions
5) references, and
6) your fully annotated RStudio script as an appendix.
It is expected that you do some research around the effects of nitrogen and phosphorus on plant growth so that you can provide a well-considered (brief) introduction to set the scene, and a discussion of your results in the context of the literature.
Your report must be submitted through turnitinThis assessment is worth 35% of your final mark
Advice:
Please read the rubric on the following pages carefully to make sure that you complete the assessment appropriately.
For guidance on how to write a scientific report refer to David Lindsay's excellent book on the reading list, and / or Chapter 1 of "A Guide to Scientific Writing" on Blackboard. These resources will be very useful for whenever you need to write a scientific report, whether for written assignments at university, or further into your career.
Refer to the computer lab notes and slides from week 8 for further information and tips.
Advice on The Islands: https://islands.smp.uq.edu.au/visitors.php
- Log into the islands using your Curtin email address using your STUDENT NUMBER email address e.g. 12345678@student.curtin.edu.au
- Make sure that you record which treatment has been assigned to which plot using the Row and Column numbers BEFORE you begin. Take a photograph or screenshot.
- When you have set up each field appropriately you should start the trial. You cannot save progress and come back to your design to start the experiment later.
- Use the same design on each Island
- BEFORE harvesting take a photograph or screenshot, so that you have a record to refer to
- When harvesting you will need to harvest each plot individually. To do this double click on each plot.
- If you need to start again you will have to harvest all of you plots first. This is easier to do if you wait a couple of days so that you can see the plants which have started to grow.
Assignment rubric
Assessment component Needs improving Acceptable Good Excellent
Introduction (max 5 marks) Limited explanation and/or purpose of research not provided<2 Limited explanation of context
Purpose of research provided2-3 A well written introduction with relevant information
A well-considered context is providedClear structure and logical flow of information
A clear purpose for research provided3-4 A well written introduction with relevant information and references
A well-considered context is providedClear structure and logical flow of information
A clear purpose for research providedAppropriate references used5
Hypothesis (max 3 marks) No hypothesis provided0 Hypothesis provided but needs major improvements1 Hypothesis provided; acceptable but could be improved
2 Hypothesis contains the required elements and is relevant to the experiment3
Methods (max 10 marks) Missing several details in site description, experimental design and statistical analysis
Inappropriate experimental design, data collection and statistical anslysisWriting style inconsistent
Incorrect use of tenses
Bullet points used<4 Site description providedSome details on experimental design and some steps taken are inappropriate and/or lackingWritten in the past tense using a non-personalised formatIncomplete details on statistical analysis
4-6 A good site description
Written in the past tense using a non-personalised formatMost details included for data collection and most steps taken in data collection are appropriateA statistical analysis section that includes an appropriate choice of data analysis and comprehensive justification of this decision, considering data assumptions and experimental design.
Details on data screening and transforming (if appropriate)
6-8 A detailed and appropriate site description
Written in the past tense using a non-personalised formatProvides a clear and comprehensive account of materials and methods used in designing the experiment and collecting the dataRelevant level of detail included and steps taken are appropriate
A statistical analysis section that includes an appropriate choice of data analysis and comprehensive justification of this decision, considering data assumptions and experimental design.
Details on data screening and transforming (if appropriate)
8-10
Results (max 12 marks) Results are not presented in an organised formatStatistical results incomplete
Tables and graphs lacking units and/or captionsPoor choice of data representation
No description of the data
<4 All hypotheses addressed.
Results missing a few statistical numbers, but mostly completeTables and growth provided, but some element incomplete or inaccurateSome description of the data, but could do with major improvementsFlow or information confusing4-7 All hypotheses addressed.
Purely descriptive no interpretation or discussion of results.
All p values, test statistics, sample sizes, alpha levels and means/other relevant values appropriately quoted.
Tables and graphs with correct units and captions
Some description of trends
Logical flow of information
7-10 All hypotheses addressed.
Purely descriptive no interpretation or discussion of results.
All tests specified, p values, test statistics, sample sizes, alpha levels and means/other relevant values appropriately quoted.
Tables and graphs with correct units and captions.
Clear and concise captions
Good choice of graphs / tables to illustrate trends in data.
A concise and logical description of the key trends with reference to tables and figures.
Logical flow of information.
10-12
Discussion (max 10 marks) Results have limited explanation and do not relate to the objectivesExplanation of the results is not supported by referencesResults have not been linked to the hypothesisLimitations of the experiment have not been identifiedNo concluding statements<4 Results have been explained but not clearly linked to the researchExplanation of results is supported by limited use of referencesResults have been linked to the hypothesisLimitations of the experiment have been identified but not linked to the outcomes of the resultsLimited conclusions
4-6 Results have been explained in the context of the researchResults explained but not also backed up with appropriate referencesResults have been linked to the hypothesisLimitations identified and clearly linked to experimental resultsAppropriate conclusions which refer to research context
Flow confusing in parts6-8 Results have been explained in the context of the research.
Explanation of results is supported by relevant references (tertiary)
Results have been linked to the hypothesisLimitations identified and clearly linked to experimental resultsAppropriate conclusions which refer to research context
Recommendations limited to the outcomes of the specific experiment.
Logical flow and structure
8-10
References (max 5 marks) Uses <2 referencesPoor reference choice
References not formatted in a consistent styleIn text referencing missing or incomplete
<2 Uses between 2-4 referencesOK reference choice (mix of tertiary and less appropriate references)
Reference formatting consistent
In text referencing incomplete/incorrect
2-3 Uses between 4-5 referencesUses references appropriate for tertiary levelReference formatting consistent
In text referencing complete and consistent
3-4 Uses >5 referencesUses references appropriate for tertiary levelReference formatting consistent
In text referencing complete and consistent
4-5
Scientific writing (max 5 marks) No evidence of structure or organisation of information
Poor paragraph structure and organisation
Inconsistent use of tenses
Use of personal pronouns
More than 5 spelling and/or grammatical errors<2 Paper written in a suitable manner with correct headingsIdeas logically sequenced
Poor scientific writing style (concise and non-repetitive)
Consistent use of tenses
Less than 5 spelling and/or grammatical errors2-3 Paper written in a clear manner with ideas logically sequenced
Concise writing and non-repetitive
Consistent use of tenses
1 or 2 spelling and/or grammatical errors3-4 Paper written in a clear manner with ideas logically sequenced using well developed paragraphsTopic sentences usedArgument structure well considered with referencesConcise writing and non-repetitive
Consistent use of tenses
1 or 2 spelling and/or grammatical errors4-5
Appendix
Annotated R Code
(max 15 marks) Code is incomplete / incorrect
Annotations may be absent<4 Some errors in code, Code is incomplete and / or not fully annotated
4-8 Code may be complete but annotations may need more work
8-12 Code is completeCode is fully annotatedCode is correct12-15
