BIOL/STATS 2244 Assignment 3: Analysis and Conclusion

Objectives

This Assignment is designed to demonstrate your current mastery of the following Learning Outcomes:

i.       Analyse data using inference procedures to address a research question

a.    Evaluate model diagnostics for common parametric inference procedures

ii.       Use statistical software to explore, summarize, analyse, interpret, and communicate data;

a.    Use R to conduct common parametric inference procedures, including model diagnostics.

b.    Use R markdown to produce reproducible analyses and reports.

iii.       Communicate statistical concepts, analyses, and arguments in an accurate and scholarly manner.

a.    Use conventional and transparent formats for reporting results of statistical analyses in written/graphical form.

To achieve these objectives, students will need to draw on course material from the topics primarily from Week 5 (Lectures and Labs). However,answering some of the interpretation work may involve using ideas from earlier topics.

How this Assignment ‘works’

This Assignment is the last of three Assignments in the course; it continues our progression through the phases of the PPDAC Framework. The major focus of this Assignment are the Analysis and Conclusion stages of PPDAC.

In  the  first  Assignment,  you  were  introduced  to  some  ‘Research  Background’  related to  aspects  of cognitive offloading and using technology to complete tasks that require accuracy. We will continue to work with this  background  (you can  refer  back to  it  if  necessary  for this  assignment).  In the  second Assignment, you were provided a dataset that is related to the Research Background; we will continue to use this dataset for this Assignment. Recall that the data is provided across TWO (2) datafiles (named trials.csv and overall.csv), and you have access to the research article that describes the way the data were collected (i.e. in the Materials and Methods section of the article) . You also have created a “Key to datasets” file that provides a brief description of the column headers in the datafiles, so you can link them to the information in the article.

As was the case with Assignment 2, you will not use every variable and/or every data point in the datafiles for this Assignment! Similarly, you likely will only need data from one of the datafiles.

Assignment Questions

Question 1.

What are the appropriate statistical hypotheses (null and alternative) that should be used to conduct

the hypothesis test to answer the Research Question described above? Write both hypotheses using

appropriate conventional symbolic format and write the null hypothesis in sentence format such that it makes it clear what is the interpretation of the symbolic format.

Question 2.

What are the conditions that must be met for the t-test to compare the difference in means between

men and women to be valid? Discuss whether each is met for our data, generating appropriate R output if/as necessary.

Question 3.

Use R to conduct the t-test to compare the difference in means between mean and women, consistent with the statistical hypotheses you stated in Question 1. You do NOT need to interpret the results.

Notes:

•    You will need to use the LaTeX abilities of R markdown to write the symbolic (i.e. equation) format for Question 1.

•    If you use any R code/output to answer a question, be sure both the code and output are showing in your knitted file.

•    This is not meant to be along assignment. Question 1 is a sentence plus the two

symbolic/equation forms of the hypotheses. Question 2 will be — perhaps —about 4-8 sentences. Question 3 will be code and output.

Grading for Assignment 2

This Assignment is less ‘flexible’ that the previous two Assignments. Where the previous Assignments   had many potential appropriate answers, this Assignment really has some ‘correct’ answers. Still, your Assignment will be graded using the same general grading scheme as the previous two Assignments.

General Overview of Grading

Your answers to the Assignment Questions will be graded based on a 4-level rubric (on page 6), which   focuses on your demonstrated level of mastery of the course-level learning outcomes listed at the start of this instructions file. What that means is that, when the graded Assignment is returned to you, you    will receive three letters that indicate which level on the rubric your submission received for the three   Learning Outcomes being evaluated.

You will be able to see the three levels and some feedback about them through Gradescope when the graded Assignment is returned. These levels will also be communicated in a ‘comment’ for an OWL

Gradebook entry for Assignment 3. To be clear, there will be no numeric mark for the Assignment (e.g. like 75% or 8/10, etc.); the three levels are the only outcome of the evaluation.

Essential Requirements and Late/Accommodated Assignments

•    Failure to submit the Assignment at all will result in a ‘0’ for the Assignment unless Academic Consideration from the Academic Counseling office of your home Faculty is received.

•    Completion of all three (3) Assignments AND earning at least 5 level P and no more than 2 level N across all three Assignments (which evaluate you on three (3) learning outcomes each) is part  of the ‘Essential Requirements’ to be eligible to earn credit (i.e. 50% or higher as a final course    grade) for the course. Failing to meet the Essential Requirements with respect to Assignments     will result in a final course grade recorded as 40% (or, your calculated course grade —whichever  is lower). This is detailed in the course syllabus, page 7.

• Late Assignments (i.e. beyond the 48-hour grace period on the official deadline, and without

academic consideration from your home Faculty’s Academic Counseling unit) will be accepted

with a late penalty, equivalent to ONE (1) rubric level) for one learning outcome (taken from the learning outcome graded at the highest level, to minimize overall impact) per 24 hours or part     thereof. To submit a late Assignment, upload your submission as you normally would. The date   of upload will be used as the date to compute any late penalty. Note that I will not accept

submissions that are more than three (3) days after the end of the 48-h grace period without academic consideration.

•    If academic consideration is received from your Faculty’s Academic Counseling office, with the consideration covering the deadline for the Assignment, arrangements should be made with

Jennifer Peter (through an OWL Message sent to “Jennifer Peter (Instructor)” group). In general, you are advised to continue to work on the Assignment (if you are physically/mentally able to)    while you wait for Counseling to review your request for consideration. You can and should also  submit your Assignment during that time if you are prepared to do so. In situations where

extended academic consideration is required, you and Jennifer will work together to find an appropriate method for completion of the Assignment.

Requests for clarification or review of grading

The graders work very hard with the rubric to grade your Assignment accurately and consistently.

Occasionally, mistakes can happen. If, after you’ve received your graded Assignment back, and have

carefully reviewed your lecture notes and feedback on the Assignment, you need clarification on some  aspect of the grading, then the process to make that request is done through Gradescope (not email or  in Student Hours, etc.). After the graded Assignment is returned, there will be a one-week opportunity to “Request Regrade” through Gradescope. This is achieved by clicking on the Assignment, clicking on “Entire submission” from the right side of the screen, and then choosing the button for Request

Regrade. This is the only method through which requests for regrades will be accepted. Jennifer and graders will not respond toregrade requests through any other form (e.g. email, OWL Message, OWL  Forums, Student Hours, etc.).

When you make your request, you should be polite and clear about which aspect(s) of your Assignment   you are seeking clarification/consideration for. Our grader will review your concern, and address it. Note that, in most situations, we will have to review your entire submission during a regrade. While it is

generally a rare outcome, it is possible for aregrade to result in a lower rubric level for some aspect of the assignment. Note that it will take sometime for the request to be addressed as the graders have    multiple responsibilities to manage; please be patient.