**Excelsior College Descriptive Statistics Questions**

You have been working in Excel to find descriptive statistics, now let’s explore how to compare means. You will need to utilize the Excel spreadsheet with your descriptives from your M1.3 assignment. Be sure to review the module notes presentation in M1.1, paying close attention to the descriptive statistics lesson, and the tab labeled “Hypothesis Testing” in particular. This video is also located in your lifeline.

When comparing means, we would like to know if they are significantly different. Keeping in mind that your data in your spreadsheet gives three different groups of data, one for 2017, 2018, and 2019, simple comparisons of means procedures typically only cover two means. Running multiple tests is not ideal, but for our purposes, let’s examine the independent-t procedure. Simply put, in this case we have the following:

Research Questions and Hypotheses

Research Question (2017-2018) Is there a significant difference in the number of accidental overdose deaths in Montgomery County in 2017 and 2018?

Research/Alternative Hypothesis There is a significant difference in the number of accidental overdose deaths in Montgomery County for 2017 and 2018.

Null Hypothesis There is no significant difference in the number of accidental overdose deaths in Montgomery County for 2017 and 2018.

Research Question (2018-2019) Is there a significant difference in the number of accidental overdose deaths in Montgomery County in 2018 and 2019?

Research/Alternative Hypothesis There is a significant difference in the number of accidental overdose deaths in Montgomery County for 2018 and 2019.

Null Hypothesis There is no significant difference in the number of accidental overdose deaths in Montgomery County for 2018 and 2019

Why might we want to explore this? Perhaps we have implemented a solution to the problem and want to see if it was effective. Maybe we just want to see if there is a difference so we can begin to look for variables that might have impacted the change. Regardless, an independent-t test can tell us if two means are significantly different.

Please review the video above on how to run an independent-t test in Excel. The Excel website in your Lifeline can help as well.

ASSIGNMENT INSTRUCTIONS

Following the video instructions, perform an independent-t test on your data sets for 2017 – 2018 and a t-test on your data sets for 2018 – 2019. Be sure to review the p value of the tests.

Are there significant differences between these years? (*Note, run two separate t-tests)

Be sure to label your output statistics on your worksheet so your instructor can identify the years you are comparing.

Imagine you are speaking to the same individual that you explained the descriptive statistics to in M1.3, again, assuming they cannot see the data and know nothing about statistics. Their question to you is, “So there are differences between the years. How large are those differences really and what does that mean?” In a separate Word document, explain what t-tests are and how they work, and give the results of your two t-tests, explaining significance and what that means.

GRADING RUBIC BELOWM1.5 Excel and Comparison of Means RubricM1.5 Excel and Comparison of Means RubricCriteriaRatingsPtsThis criterion is linked to a Learning Outcomet-test 1

20 ptsExemplaryYour t-test has been run accurately for the comparison of means between 2017 and 2018 data. Output statistics are clearly identified. 10 ptsProgressingYour t-test has been run for the comparison of means between 2017 and 2018 data. Output statistics are identified. There are some errors. 0 ptsNot addressed or Not submittedYour t-test and output statistics comparing the means between 2017 and 2018 are inaccurate or missing.

20 pts

This criterion is linked to a Learning Outcomet-test 2

20 ptsExemplaryYour t-test has been run accurately for the comparison of means between 2018 and 2019 data. Output statistics are clearly identified. 10 ptsProgressingYour t-test has been run for the comparison of means between 2018 and 2019 data. Output statistics are identified. There are some errors. 0 ptsNot addressed or Not submittedYour t-test and output statistics comparing the means between 2018 and 2019 are inaccurate or missing.

20 pts

This criterion is linked to a Learning OutcomeExplanation of Statistics

50 ptsExemplaryYou accurately describe results in common terminology and detail what each t-test tells the reader about the data sets. Details important differences in the two comparisons. 42 ptsProficientYou describe results in common terminology and detail what each t-test tells the reader about the data set. Minor details need further development. 34 ptsProgressingYou provide a general description of what each t-test tells the reader about the data set. Some terminology is too technical. Your description needs more information for the reader to understand the data sets. 26 ptsIncompleteYour description of what each t-test tells the reader is unclear, too technical, and/or inaccurate. 0 ptsNot addressed or Not submittedDoes not address this criterion in the assignment. Did not submit assignment. Does not adhere to academic honesty policy.

50 pts

This criterion is linked to a Learning OutcomeDue Date

10 ptsExemplarySubmitted by due date. 8 ptsProficientSubmitted one day after due date. 6 ptsProgressingSubmitted two days after due date. 4 ptsIncompleteSubmitted three days after due date. 0 ptsNot addressed or Not submittedSubmitted four or more days after due date.

10 pts

Total Points: 100PreviousNext

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