代做data collection、Matlab设计代写、Matlab代做留学生、代做Matlab编程

日期：2018-09-26 10:09

MASSEY UNIVERSITY

College of Sciences

Institute of Natural and Mathematical  Sciences (Statistics)

Introductory Statistics 161.120

Assignment 1

Due date: Sunday 23rd September 2018Assessment value: 10%

Note:

?This assignment involves data collection and will take several days to plan and complete. Don’t leave it until the last minute!

?Your report should preferably be computer produced but there will be no penalty if it is neatly hand written.

?You are expected to use Excel for your analyses with the output incorporated into your report.

The objective of this experiment is to explore and model the effect of a single categorical variable on the length of leaves. In place of leaf lengths you could use another variable such as the width of leaves, or the number of leaves on a branch or on a bush.

The measurements need to include one (1) continuous numerical variable (the response) and one (1) categorical variable (an explanatory factor) with two levels.

You do not need an equal number of replicates in each level of your categorical variable BUT you do need at least 15 measurements at each level of your categorical variable.

Choose a research question to investigate. One of the following can be used, but you can also use a different question based on another numerical response measurement and/or another categorical factor that can be varied.

1.  Does position on the bush (e.g north/south facing, or inside/outside, or high/low) affect the length of leaves on a bush?

2.Considering more than one bush of the same type of tree: does the length of leaves vary between bushes of different heights?

3.If you want to investigate a different research question, please contact your lecturer to discuss its suitability.

Bear in mind the following guidelines:

?You need to plan how you will sample from the bush(es) considering replication and randomisation.

?Do not destroy what you are sampling!  A bushy tree might survive a sample of leaves plucked from it, but try to make your measurements leaving foliage intact especially if using trees on campus!

?You may want the help of at least one friend to collect your data.

?If your friend is also doing this paper, the collected data must be unique for each student (i.e. you may not share the data). You can plan and carry out the data collection together, but you will need to repeat the data collection process, so you have different data to each other.

?Subsequent analysis of the data and report writing (including description of methods used) must be done independently.

?You may need to carry out a small pilot survey to check whether your methodology will work.

Keep a record of your data. It will be needed for Assignment 2.

Prepare a report of no more than 6 pages, by answering the following questions in the answer spaces provided.  You can re-size the answer spaces.

This report is marked out of 40 marks. Mark allocation is noted next to each section heading.

Note that 3 of these marks will be given for presentation.

Presentation[3 marks]

Your report length should be no more than six pages including graphics but excluding data.

1 mark for staying within the 6 page limit (excluding raw data) and for

             1 mark for  overall effective presentation (NOT for “prettiness”!)

1 mark for readability/flow   and  spelling/grammar

Part A: Introduction[3 marks]

1.State the research question you investigated.

2.Describe the variables you used and how you measured them, including the units used for your numeric variable.

Part B: Survey design and data collection[15 marks]

1.First Think ![ 6 marks ]

a)Suppose I have chosen my tree and I stand on the north side of it with my eyes closed, reach out in what I think of as a “random” direction,  and measure the first leaf I touch.   I do this 15 times.   How am I potentially introducing bias into my sample, and what might be the lurking variable(s)?  [ 2 marks]

b)Suppose I was to   1. randomly choose a twig and then 2.  measure all leaves on the twig.  What is this method of sampling called?  Suggest an advantage and a disadvantage of this approach.                     [ 2 marks ]

c)Suppose leaves tend to be smaller near the tip of a twig and bigger further along  the twig.  Suggest a data collection strategy to avoid bias in your sample selection? [2 marks]

2.Now for your survey[9 marks ]

If you collected the data with a classmate, give this person’s name and ID number:

Name: _____________________________ ID Number: ______________________

Describe what you did and why you made the decisions you did.  

Include:

?Details about sample selection, sample size and data collection (including where and when).

?Details on what the levels of your categorical variable are.

?Details on how you recorded your numerical variable.

?Describe your use of randomisation: how did you do it? How did you apply it?

?Comment on any practical difficulties you encountered.

?Changes you would make to your method if you were going to repeat this task.

Ensure you include enough detail so that someone reading your report could repeat your data collection method.

Attach a copy of your data to your report as an appendix.

Keep an electronic copy of the data for use in Assignment 2.

Write your answer here

Part C: Data analysis [15 marks]

Use Excel and incorporate the output into your report.

1. Simple descriptive analysis    [9 marks]

?Draw  boxplots of your numerical variable, for each of the two levels of the categorical variable.

?For each level of your categorical variable, produce numerical summaries of the numerical variable. Include the sample size, mean, standard deviation and the five number summary.

?Describe the important features of your data, as shown by your graphs and numerical summaries.

(Write your answer and paste your graphs and excel output here)

2. Confidence intervals     [6 marks]

?For each level of your categorical variable, produce a 95% confidence interval for the mean of your numeric variable.

?Interpret the confidence intervals in the context of your research question.

(Write your answer and paste your graphs and excel output here)

Part D: Discussion and Conclusion[4 marks]

Discuss what your analysis tells you about your research question. Comments should consider the following questions:

?Are you able to answer the initial question?

?Are there any other issues that might need to be considered in answering the initial question?

?Are you able to generalise what you have learnt to any other population beyond the bushes you observed?

Write your answer here

Appendix: (Not included in page count)

Paste your data here