INFO 630—EVALUATION OF INFORMATION SYSTEMS
ASSIGNMENT #2
Name: ________________________
Date: ____________
Show your work for all problems done manually (outside of SPSS).
This assignment is to be done individually. The due date is on the syllabus.
1. Import the data set “project.xls”. (Launch SPSS and “Open an existing data source”. Change
the desired file type from SPSS (*.sav) to Excel. Open “project.xls”. Have it “Read variable
names”. Save the data file as “project.sav”.)
This file contains summary project data, including the size of the project (in function points),
the overall duration or schedule of the project (in calendar months), and the total amount of
effort needed to develop the project (in staff months).
a) Plot Schedule (Y) versus Effort (X) using a simple scatter plot.
b) Generate a linear and power regression analysis for Schedule (dependent) vs. Effort
(indep.). (Use Analyze/Regression/Curve Estimation. Choose Linear and Power Models,
and select “Display ANOVA table”.) The power regression finds the best fit for equations
of the form
(dependent variable Y) = (Const.)*(indep. variable X)(B)
where “B” is the value of B for the variable X, and “Const.” is the value of B for the row
labeled “Const.”
c) Create a table showing the R Square and Standard Error for both Linear and Power
models.
d) Choose the best-fitting model for Effort versus Schedule. Write the equation which best
models the relationship between effort and schedule, including standard error terms.
e) Prove that the 95% confidence interval for the two constants in the best-fitting model
does not include zero. Why is this an important thing to check?
f) Based on the curve fit graph, would you trust the model chosen in part d) for small
projects? For large projects? Explain your answers.
g)
In McConnell, Rapid Development, a relationship between schedule estimate in months
and total staff months expended on a software project is given by:
Schedule = 3.0 x (Effort)1/3
How does your conclusion from part d) compare to this result?
More specifically, do the values of your coefficients agree with McConnell’s, to a 95%
level of confidence? Show your work.
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2. Open the data file “ev.sav”. This shows the earned value data for a project, after nine months
into a two year project. The reporting “period” is monthly, and the values for BCWP, ACWP,
and BCWS are in thousands of dollars ($K).
a) What is the BAC (budget at completion) for this project (duration and cost)?
b) Create new variables, and calculate the SPI and CPI (schedule and cost performance
indices) for each reporting period to date. (Transform/Compute)
c) Make a line graph of SPI and CPI versus reporting period. Use Graphs/Line/Multiple for
“Values of individual cases” (in SPSS 15 or later, Graphs/Legacy Dialogs/Line/Multiple).
Lines represent cpi and spi, and the Category Label is the Variable “period”. Indicate
graphically when CPI and SPI went into the green, yellow, or red zones as defined by the
US Marines (per slide 39 of week 3 lecture). The latter can be done manually in Word
after pasting the graph, using the Drawing toolbar.
d) Make and show a line graph of BCWP, ACWP, and BCWS versus period.
e) Based on the trends seen in part c), determine the EAC. Explain how you arrived at this.
Remember to give both cost and schedule components.
f) What are the projected cost and schedule overruns? How would you describe the state of
this project in terms of cost and schedule?
g) As of the ninth month, how much money was actually spent on the project?
h) As of the ninth month, what are the cost variance, schedule variance, and schedule slip?
3. Suppose your organization has defined two corporate goals:
1. Have fun.
2. Make money.
Identify the organization for which you are conducting this analysis (you pick!).
Then for both of those two goals:
a. Define four subgoals you could reasonably base on each of those two goals above.
b. Then take one of each four subgoals and devise a active structured statement to
express how a measure could be used to assess whether you are meeting that subgoal
(hence you have to determine what the measure is, and how you’re going to measure it).
See week 4, slide 19 for examples.
c. Define each measure, including any assumptions about its scope, and show how to
calculate the measure.
d. Assume you’re going to plot each measure over time (you pick a relevant time
interval), and choose a suitable indicator to plot the measure. This plot should also
include a goal value for this measure. Make up some sample data and show a sample of
what this indicator will look like.
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e. Determine how you will collect the data elements needed for this measure (i.e. how
will you collect the data elements needed to calculate the measure). Describe what those
data elements are, and how they will be collected.
In summary, you are given two goals. You will define a total of eight subgoals (four per goal). You will select two
of those eight subgoals (one per goal), and for each of those two subgoals: come up with an active structured
statement, define a measure, choose and show an indicator with that measure, and define the data elements and their
source.
(Sounds like a lot, but it’s fiction so it’s not that hard to come up with.)
4. Given the following history of problems found and fixed (i.e. new and closed) during the first
ten weeks of a project.
a) Plot the BMI versus time with a run chart.
b) Is the project doing well at resolving problems? Explain.
c) What is the trend for the future? Explain.
d) What is the cumulative number of problems unresolved at the end of this ten week period?
Week # new problems # closed problems
1
8
3
2
11
6
3
9
7
4
11
8
5
14
11
6
14
12
7
21
17
8
17
14
9
13
11
10
14
13
3
INFO 630 Assignment 2 grading scale
Problem
1a
1c
1d
1e
1f
1g
2a
2c
2d
2e
2f
2g
2h
3
4a
4b
4c
4d
TOTAL
Points
1
2
1
1
1
2
1
3
1
2
2
1
2
6
1
1
1
1
30 points
4