statistics
STAT200: Written Assignment #1 – Descriptive Statistics Data Analysis Plan – Instructions
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STAT200 Introduction to Statistics
Assignment #1: Descriptive Statistics Data Analysis Plan
Assignment #1: Prepare Descriptive Statistics Data Analysis Plan
Before conducting any statistical analyses, researchers develop a plan for how they will analyze their
data to answer their research questions. The purpose of this assignment is to provide an experience
developing a descriptive statistics analysis plan. Note: This first assignment is a plan only; no statistics
will be calculated or graphs created. The second assignment will involve carrying out the plan, after
receiving feedback from your instructor.
Assignment Steps:
Step #1: Review the STAT200 data set file. (Note: This data set will be used for all three of this terms
written assignments).
The data is a subsample from the US Department of Labors Consumer Expenditure Surveys (CE) and
provides information about the composition of households and their annual expenditures
(https://www.bls.gov/cex/). Detailed information on the sample and variables is included with the data
set file; please carefully review this information to familiarize yourself with the data (Note: This
information will be used in Assignment #2 to describe the dataset).
Step #2: Develop descriptive statistics data analysis plan.
Task 1: Develop scenario. Imagine that you are head of a household and have to determine a
household budget plan based on the data available from the dataset. For instance, you are a 35
year old single parent with a high school diploma and one child.
Task 2: Select variables for analysis that match the scenario developed in Task 1.The data set
provides information on household consumption; there are socioeconomic variables and
expenditures variables. The socioeconomic variable names start with SE- and the expenditure
variable names start with a USD; all expenditures are in US dollars. All students must use
income as one variable. Select two additional socioeconomic variables (one qualitative and one
quantitative) and two expenditures for your analysis that match the scenario you developed for
Task 1. For instance, using the example scenario of a 35 year old single parent with a high
STAT200: Written Assignment #1 – Descriptive Statistics Data Analysis Plan – Instructions
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school diploma and one child, you could select income, education, and number of children
as socioeconomic variables and then pick two household expenditure items to show the
distribution of costs and compare that with your income. When selecting variables, think about
the following three questions:
o Why am I choosing these variables?
o What interests me about these variables?
o What do I think will be the outcome?
Task 3: Determine appropriate measures of central tendency and dispersion for the selected
variables. For each quantitative variable, select at least one measure of central tendency and at
least one measure of dispersion (Please see below table for list of measures). For the qualitative
variable, select one measure of central tendency. When determining the measures of central
tendency and dispersion, think about what is appropriate given the level of measurement and
type of variable. Recommend referring to the text and information posted in our LEO classroom
to help with this task (Note: you will use this information to provide a rationale for your choice
of measures).
Measures of Central Tendency Measures of Dispersion
Mean
Mode
Median
Range
Sample Standard Deviation
Variance
Task 4: Determine appropriate graph and/or table for each of the selected variables. Select
one graph or table for each variable (Please see below table for list of graphs and tables). When
determining the graphs and tables, think about what is appropriate given the level of
measurement and type of variable. Recommend referring to the text and information posted in
our LEO classroom to help with this task (Note: you will use this information to provide a
rationale for your choice of graphs and/or tables).
Types of Graphs Types of Tables
Pie Chart
Bar Chart
Histogram
Box Plots (also known as Box-and-Whiskers Plot)
Frequency Table
Relative Frequency Table
Grouped Frequency Table
STAT200: Written Assignment #1 – Descriptive Statistics Data Analysis Plan – Instructions
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Step #3: Complete the Assignment #1: Descriptive Statistics Data Analysis Plan Template.
Remember, you will not be conducting any statistical analysis, drawing any graphs, or compiling any
tables for the first assignment. Rather, you need to wait for feedback from your instructor on this
assignment and use that feedback to complete Assignment #2.
Here are the main sections for this assignment (i.e., completing the plan template):
Identifying Information. Fill in information on name, class, instructor, and date.
Scenario. In this section, briefly (2-3 sentences) describe the scenario you developed in Step #2,
Task 1.
Complete Table 1: Variables Selected for the Analysis. Enter information the variables selected
for analysis in Step #2, Task 2. For each selected variable be sure to include its: name as listed in
the data set, description, and variable type.
Reason(s) for Selecting the Variables and Expected Outcome(s): In this section, for each
selected variable, please answer the following questions:
Why did I choose this variable?
What interests me about this variable?
What do I think will be the outcome?
Complete Table 2. Numerical Summaries of the Selected Variables. Enter information on
selected measures of central tendency and dispersion for each selected variable. Be sure to
briefly explain why you choose those measurements. Note: The information for the required
variable, Income, has already been completed and can be used as a guide for completing
information on the remaining variables.
Complete Table 3. Type of Graphs and/or Tables for Selected Variables. Enter information on
selected graph and/or table for each selected variable. Be sure to briefly explain why you
choose those measurements. Note: The information for the required variable, Income, has
already been completed and can be used as a guide for completing information on the
remaining variables.
Assignment Submission: Name the file that contains your completed Assignment #1: Descriptive
Statistics Data Analysis Plan Template using the following format: Assignment1-StudentLastName.
STAT200: Written Assignment #1 – Descriptive Statistics Data Analysis Plan – Instructions
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Then, submit the file via the Assignments area in the LEO classroom in the Assignment #1: Descriptive
Statistics Data Analysis Plan folder and wait for your instructors feedback.
Grading Rubric for Written Assignment #1
Scenario and Selection of Related Variables
Clear description of scenario
Selected variables and reasons are appropriate for the scenario.
20%
Selection of Measures of Central Tendency and Dispersion
For each variable:
Appropriate measures selected.
Rationale is provided and appropriate.
30%
Selection of Graphs and/or Tables
For each variable:
Appropriate measures selected.
Rationale is provided and appropriate.
30%
Writing Quality:
Completes all sections of template.
Writes clearly, concisely, and with few errors.
20% STAT200: Assignment #1 – Descriptive Statistics Analysis Plan – Template
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University of Maryland University College
STAT200 – Assignment #1: Descriptive Statistics Data Analysis P
lan
Identifying Information
Student (Full Name):
Class:
Instructor:
Date:
Scenario: Please write a few lines describing your scenario and the four variables (in addition to income) you have selected.
Use Table 1 to report the variables selected for this assignment. Note: The information for the required variable, Income, has already been completed and can be used as a guide for completing information on the remaining variables.
Table 1. Variables Selected for the Analysis
Variable Name in the Data Set
Description
(See the data dictionary for describing the variables.)
Type of Variable
(Qualitative or Quantitative)
Variable 1: Income
Annual household income in USD.
Quantitative
Variable 2:
Variable 3:
Variable 4:
Variable 5:
Reason(s) for Selecting the Variables and Expected Outcome(s):
Variable 1: Income –
Variable 2: –
Variable 3: –
Variable 4: –
Variable 5: –
Data Set Description
:
Measures of Central Tendency and Dispersion
Complete Table 2. Numerical Summaries of the Selected Variables and briefly explain why you choose those measurements. Note: The information for the required variable, Income, has already been completed and can be used as a guide for completing information on the remaining variables.
Table 2. Numerical Summaries of the Selected Variables
Variable Name
Measures of Central Tendency and Dispersion
Rationale for Why Appropriate
Variable 1:
Income
Number of Observations
Median
Sample Standard Deviation
I am using median for two reasons:
If there are any outliers or the data is not normally distributed, the median is the best measure of central tendency.
The variable is quantitative.
I am using sample standard deviation for three reasons:
The data is a sample from a larger data set.
It is the most commonly used measure of dispersion.
The variable is quantitative.
Variable 2:
Variable 3:
Variable 4:
Variable 5:
Graphs and/or Tables
Complete Table 3. Type of Graphs and/or Table for Selected Variables and briefly explain why you choose those graphs and/or tables. Note: The information for the required variable, Income, has already been completed and can be used as a guide for completing information on the remaining variables.
Table 3. Type of Graphs and/or Tables for Selected Variables
Variable Name
Graph and/or Table
Rationale for why Appropriate?
Variable 1:
Income
Graph: I will use the histogram to show the normal distribution of data.
Histogram is one of the best plot to show the normal distribution of quantitative level data .
Variable 2:
Variable 3:
Variable 4:
Variable 5: STAT200 Introduction to Statistics
Dataset for Written Assignments
Description of Dataset:
The data is a random sample from the US Department of Labors 2016 Consumer Expenditure Surveys (CE) and provides information about the composition of households and their annual expenditures (
https://www.bls.gov/cex/
). It contains information from 30 households, where a survey responder provided the requested information; it is all self-reported information. This dataset contains four socioeconomic variables (whose names start with SE) and four expenditure variables (whose names start with USD).
Description of Variables/Data Dictionary:
The following table is a data dictionary that describes the variables and their locations in this dataset (Note: Dataset is on second page of this document):
Variable Name
Location in Dataset
Variable Description
Coding
UniqueID#
First Column
Unique number used to identify each survey responder
Each responder has a unique number from 1-30
SE-MaritalStatus
Second Column
Marital Status of Head of Household
Not Married/Married
SE-Income
Third Column
Annual Household Income
Amount in US Dollars
SE-AgeHeadHousehold
Fourth Column
Age of the Head of Household
Age in Years
SE-FamilySize
Fifth Column
Total Number of People in Family (Both Adults and Children)
Number of People in Family
USD-Annual Expenditures
Sixth Column
Total Amount of Annual Expenditures
Amount in US Dollars
USD-Housing
Seventh Column
Total Amount of Annual Expenditure on Housing
Amount in US Dollars
USD-Electricity
Eighth Column
Total Amount of Annual Expenditure on Electricity
Amount in US Dollars
USD-Water
Ninth Column
Total Amount of Annual Expenditure on Water
Amount in US Dollars
How to read the data set: Each row contains information from one household. For instance, the first row of the dataset starting on the next page shows us that: the head of household is not married and is 59 years old, has an annual household income of $94,929, a family size of 2, annual expenditures of $55,247, and spends $18,483 on housing, $1,451 on electricity, and $546 on water.
UniqueID#
SE-MaritalStatus
SE-income
SE-AgeHeadHousehold
SE-FamilySize
USD-AnnualExpenditures
USD-Housing
USD-Electricity
USD-Water
1
Not Married
94929
59
2
55247
18483
1451
546
2
Not Married
96621
54
2
55746
18149
1455
540
3
Not Married
96664
53
3
55558
18502
1478
553
4
Not Married
96522
43
4
56152
18483
1457
537
5
Not Married
96697
49
2
56453
18520
1469
545
6
Not Married
96727
39
2
56440
18376
1441
542
7
Not Married
94867
60
1
55512
18633
1485
523
8
Not Married
96690
57
2
56097
18334
1453
535
9
Not Married
97469
35
4
54929
18514
1451
565
10
Not Married
96886
44
2
55321
18312
1450
523
11
Not Married
95744
52
4
55963
18435
1465
555
12
Not Married
96572
59
2
56515
18648
1480
552
13
Not Married
95366
48
2
57082
18576
1478
538
14
Not Married
97912
49
1
55704
18619
1450
553
15
Not Married
96928
43
3
55932
18701
1479
520
16
Married
114051
42
5
84486
25728
1452
818
17
Married
106627
56
3
82676
22414
1688
709
18
Married
109312
37
6
80801
25392
1514
743
19
Married
103144
29
5
75393
26322
1386
626
20
Married
111195
30
5
80865
25018
1481
796
21
Married
112559
39
3
80934
25531
1504
794
22
Married
97835
30
5
77765
27949
1297
641
23
Married
100693
42
2
73294
26102
1354
597
24
Married
95385
50
4
74110
22847
1302
684
25
Married
100350
31
5
73771
26853
1405
585
26
Married
95922
55
3
72228
22996
1326
674
27
Married
96207
27
3
74620
28491
1310
588
28
Married
97663
51
3
72971
23150
1320
689
29
Married
100565
18
3
69203
27950
1358
626
30
Married
97977
44
2
73198
22990
1298
696
