Keenan LewisSTAT100 Activity_5_Worksheet

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STAT100 Fall 19 Class Activity 5 – Student Worksheet
Unit 3: Exploratory Data Analysis
Names (Include full names of all group members) – Note that if your name is on this document, you must be in attendance in class (unless you have a documented excused absence): Keenan Lewis
*Spoke with Prof. Griffin to submit the class activity late because my laptop died in class.
Is your group willing to share your document with the class (Yes or No)?:
Activity 5: Examining Distributions Summary
In this activity, you will generate data displays and numerical measures and interpret results. 
Learning Objectives:
Summarize the distribution of a categorical variable
Generate graphical displays of the distribution of a quantitative variable and use them to summarize the overall pattern of the distribution
Generate numerical measures of center and measures of spread of the distribution of a quantitative variable and use them to summarize the distribution
The data file for this activity contains data that was collected from students enrolled in introductory statistics courses in various colleges and universities in MD. The population of interest is all students enrolled in introductory statistics courses in the US. Thus, we can use this data set to make claims about all students enrolled in introductory statistics courses in the US.
Part 1 – Summarize the distribution of a categorical variable:
Open the Course Data file. The objective is for you to generate visual displays to examine the distribution of the Expected_grade variable. For this question, students were asked what grade they expected in the statistics course. Generate at least 2 visual displays to examine the distribution of the Expected_grade variable. Paste below any output that you think effectively summarizes the distribution of that variable.
In a few sentences describe the distribution of the Expected_grade variable. Be sure to focus on the different values that the variable takes and how often the variable takes those values. What does the output you included in question #1 tell you about how students responded to the survey question for this variable?
According to the graphs, I can describe the distribution as not symmetrical and skewed right given that the overwhelming majority of the students chose “A”.
If you were to pick one student at random from the Course Data Set, how do you think that student would respond when asked what grade they expected in the statistics course? Refer to evidence from question #1 to support your reasoning.
If I were to pick a student at random most likely they will say that they would expect a grade of “A”. The reason is because 57.9% of the class expected chose a grade of “A” making the possibility of choosing someone very likely.
Did any students not respond to the survey question for the Expected_grade variable? If so, how many did not respond (give both as a count and as a percent of the total sample size)? 
Yes, there were students who didn’t answer the question. 8 students or 0.58% of the students did not answer the question.
Part 2 – Summarize the distribution of a quantitative variable:
Open the Course Data file. The objective is for you to generate visual displays and numerical measures to examine the distribution of the Height_inches variable. For this question, students were asked to provide their height in inches. Generate a histogram and a box plot for the Height_inches variable. Paste below the histogram and box plot.
 
Next, in a few sentences describe the distribution of the Height_inches variable. Be sure to focus on the different values that the variable takes and how often the variable takes those values. Also, describe the center, shape, and spread of the distribution of the Height_inches variable, and describe whether you notice any outliers. Refer to output included in question #6 to support your claims about the distribution of the variable.
The distribution of the Height in inches if fairly symmetrical, given that the median and mean are very similar. I would also describe it as unimodal because it has one drastic peak with just a few bumps. The measure of center would be the mean given that the graph is symmetrical. The spread of the distribution would be 26 inches.
List below the mean, median, standard deviation and IQR for the Height_inches variable.
The Mean is 66.235, the median is 66, the standard deviation is 4.350, and the IQR is 7.
What would you say is a typical or expected value for the Height_inches variable? Refer to any evidence from above to support your reasoning.
I believe The median or mean is an expected value of the “Height inches” because the majority of the students are female and the average height of a female is around 5’2 or 62 inches.
Did any students not respond to the survey question for the Height_inches variable? If so, how many did not respond (give both as a count and as a percent of the total sample size)?
10 students did not respond to the survery questions which is about 0.7%.