Assessment 3: Experimental design Due date: 5pm Friday 2nd June (see unit outline for submission details) 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 through the completion of these tasks, and to provide feedback that will be useful for future assessment tasks. 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 copy from another student. Please read the following information regarding plagiarism carefully: Plagiarism Monitoring University Policy Regarding Relevant Student Rights & Responsibilities: Academic misconduct is defined as acting dishonestly or unfairly in connection with any examination of other academic work. It includes: Presenting copied, falsified or improperly obtained data as if it were the result of laboratory work, field trips or other investigatory work; Including in the student’s individual work material which is the result of significant assistance from another person if that assistance was unacceptable according to the instructions or guidelines for that work; Assisting another student in the presentation of that student’s individual work in a way that is unacceptable according to the instructions or guidelines for that work; Cheating; or Plagiarising. Cheating is dishonest conduct in relation to assessment. It includes: Copying from other students; or Use of cheat notes and inappropriate use of graphic calculators in examinations Plagiarism is knowingly presenting the work or property of another person as if it were one’s own without appropriate acknowledgment or referencing. It includes: Word for word copying of sentences or paragraphs from one or more sources which are the work or data of other persons (including books, articles, theses, unpublished works, working papers, seminar and conference papers, internal reports, lecture notes, tapes or works of creative art); Closely paraphrasing sentences, paragraphs or themes; Using another person’s ideas, work or research data without due acknowledgment; Submitting work which has been produced by someone else on the student’s behalf as if it were the work of the student; Copying or submitting computer files in whole or part without indicating their origin; or In the case of collaborative projects, falsely representing the individual contributions of the collaborating students where individual contributions are identified. Offending students will be dealt with under the Curtin University of Technology Act 1996 - Statute 10, Student Disciplinary Statute, Sections 2 and 4. Further information on enrolment, plagiarism, etc can be found at: htttp://www.policies.curtin.edu.au 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 regards to how much phosphate and/or nitrogen you add. As well as working out which fertiliser mix provides the best yield, you also need to determine if the effects 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. 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 a length of a season (3 months). Following a growing period, you can assess the impact of variable fertiliser treatments by measuring the height of the plant, counting the fruit, flowers or leaves, as well as harvesting the plant to provide a yield. For this task, you have to design a field experiment that determines which fertiliser treatment results in significantly better crop performance and determine if these differences are consistent between islands. Whilst designing your experiment you will need to consider replication, randomisation and controls. It is recommended that you conduct a priori power analysis to determine the appropriate number of samples per treatment. To carry out the a priori power analysis, you conduct some background research to determine the effect size, and decide that a value of 0.5 is most appropriate. Assignment instruction: You are to write up your experiment in the format of a paper and should include a short introduction that includes the purpose of the experiment, a detailed and concise methods section which also includes a site description, a results section with appropriate tables and graphs, and a discussion with conclusions. It is also expected that you do a little bit of research around the effects of nitrogen and phosphorus on plant growth so that you can provide a well-considered discussion of your results. Please submit your RStudio script as your appendix. This assessment is worth 30% of your final mark Please read the rubric on the following pages carefully to make sure that you complete the assessment appropriately 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 rubric Assessment component Needs improving Acceptable Good Excellent Introduction (max 5) Limited explanation and/or purpose of research not provided <2 Limited explanation of context Purpose of research provided 2-3 A well written introduction with relevant information A well-considered context is provided Clear structure and logical flow of information A clear purpose for research provided 3-4 A well written introduction with relevant information and references A well-considered context is provided Clear structure and logical flow of information A clear purpose for research provided Appropriate references used 5 Hypothesis (max 3) No hypothesis provided 0 Hypothesis provided but needs major improvements 1 Hypothesis provided; acceptable but could be improved 2 Hypothesis contains the required elements and is relevant to the experiment 3 Methods (max 10) Missing several details in site description, experimental design and statistical analysis Inappropriate experimental design, data collection and statistical anslysis Writing style inconsistent Incorrect use of tenses Bullet points used <4 Site description provided Some details on experimental design and some steps taken are inappropriate and/or lacking Written in the past tense using a non-personalised format Incomplete details on statistical analysis 4-6 A good site description Written in the past tense using a non-personalised format Most details included for data collection and most steps taken in data collection 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) 6-8 A detailed and appropriate site description Written in the past tense using a non-personalised format Provides a clear and comprehensive account of materials and methods used in designing the experiment and collecting the data Relevant 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) Results are not presented in an organised format Statistical results incomplete Tables and graphs lacking units and/or captions Poor choice of data representation No description of the data <4 All hypotheses addressed. Results missing a few statistical numbers, but mostly complete Tables and growth provided, but some element incomplete or inaccurate Some description of the data, but could do with major improvements Flow or information confusing 4-7 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 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) Results have limited explanation and do not relate to the objectives Explanation of the results is not supported by references Results have not been linked to the hypothesis Limitations of the experiment have not been identified No concluding statements <4 Results have been explained but not clearly linked to the research Explanation of results is supported by limited use of references Results have been linked to the hypothesis Limitations of the experiment have been identified but not linked to the outcomes of the results Limited conclusions 4-6 Results have been explained in the context of the research Results explained but not also backed up with appropriate references Results have been linked to the hypothesis Limitations identified and clearly linked to experimental results Appropriate conclusions which refer to research context Flow confusing in parts 6-8 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 hypothesis Limitations identified and clearly linked to experimental results Appropriate conclusions which refer to research context Recommendations limited to the outcomes of the specific experiment. Logical flow and structure 8-10 References (max 5) Uses <2 references Poor reference choice References not formatted in a consistent style In text referencing missing or incomplete <2 Uses between 2-4 references OK reference choice (mix of tertiary and less appropriate references) Reference formatting consistent In text referencing incomplete/incorrect 2-3 Uses between 4-5 references Uses references appropriate for tertiary level Reference formatting consistent In text referencing complete and consistent 3-4 Uses >5 references Uses references appropriate for tertiary level Reference formatting consistent In text referencing complete and consistent 4-5 Scientific writing (max 5) 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 headings Ideas logically sequenced Poor scientific writing style (concise and non-repetitive) Consistent use of tenses Less than 5 spelling and/or grammatical errors 2-3 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 errors 3-4 Paper written in a clear manner with ideas logically sequenced using well developed paragraphs Topic sentences used Argument structure well considered with references Concise writing and non-repetitive Consistent use of tenses 1 or 2 spelling and/or grammatical errors 4-5 Self-reflection: This assignment will not be accepted unless you have completed this section! Mark your assignment using the rubric above. For each assignment component, indicate whether you think you have achieved a fail, pass/credit or distinction/high distinction. Assignment component Needs improving Acceptable Good Excellent Introduction Methods Results Discussion Scientific writing style For any of the assignment components that you have indicated a fail or pass/credit, please answer the following questions: Did you want/aim to achieve a distinction/high distinction in this assignment component? What prevented you from achieving a distinction/high distinction in this assignment component? What strategies/resources could you have used to achieve a distinction in this assignment component?