A Brief Introduction to the
SITATION Software
Mark S. Daskin
Department of IOE, Univ. of Michigan
Ann Arbor, MI 48109
Summer, 2010
What is SITATION?
Software to solve location problems
Set covering
P-median
Maximal Covering
Uncap. Fixed charge
P-center
Loc./Inv. model
Partial covering P-center
Partial covering Set covering
Covering-Median Tradeoff
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
2
Options include
 Forcing sites in/out of solution
 Different solution algorithms
Heuristic
Improvement
Lagrangian relaxation in branch and bound (optimal)
 Mapping
 Reporting
 Manual facility exchanges (for some objectives)
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
3
Main Menu
First you load the data
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
4
Loading the data
Specify distance metric
Euclidean
Great circle
Manhattan
Network
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
5
Specify file to read
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
6
Basic input file format
1 73.945478 40.670543 7322564 2819401 189600 < New York NY >
Node number, longitude, latitude, demand 1, demand 2, fixed cost, <city name >
Demand 2 is usually ignored,
but you can take a weighted sum of
Demand 1 and Demand 2
if you want to do so
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
7
Specify how distances are to be
obtained
Specify how distances
are to be obtained
computed
from a file
Network distances must
be read from a file!
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
8
Now set key parameters
Set key parameters
coverage distance
cost per demand per mile
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
9
Specify key parameters
Values used for REPORTING purposes
even if not used in optimization
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
10
Also force nodes into/out of
solution
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
11
Now you can run a problem
Run a single objective model
Or a multi-objective model
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
12
Select objective function
Not all available
in free student
version
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
13
Select an algorithm
Available
algorithms
depend on
problem
selected
for solution.
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
14
Specify number to locate
-1 for some
Problems
(e.g., uncap
fixed charge)
allows
program to
determine
optimal value
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
15
Set Lagrangian parameters
Parameters control
Lagrangian effort
and other related
options
(substitution,
intermed. Display,
branch and bound,
Initial lag mult.,
Etc.)
USE Defaults if not
sure what to do.
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
16
Watch Lagrangian Progress
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
17
Now see, map, change results
Tabular and graphical summaries
Map results
Exchange, delete, add sites
manually
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
18
Select summary result to display
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
19
Basic summary
Shows input
values,
problem
selected,
bounds,
iterations,
B&B nodes,
seconds, etc.
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
20
Extended summary shows
Shows
locations,
coverage,
average
distance,
total cost,
etc.
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
21
Number of times covered…
Shows
number of
nodes and
demands
covered 0
times, 1 time,
2 times, etc.
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
22
Assignment to sites
Shows
facility
assigned to
each site,
distance to
site, demand,
dem*dist,
total
dem*dist,
Max dist
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
23
Node to facility report
Shows similar information
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
24
Tradeoff summary info
Center-median
shows solution
values, whether
findable using
weighting
method, penalty
for distances
greater than
max distance,
and locations
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
25
Graph of tradeoff
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
26
Zoom in on a region of a graph or
map
By dragging
from top left to
bottom right of
region to
enlarge.
Drag from
bottom right to
top left to undo
enlargement.
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
27
Alter how graph is displayed
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
28
Show only solutions findable
using weighting method
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
29
Force assignments report/menu
Allows
manual
assignment
of demands
to facilities
for location/
inventory
model
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
30
Map of the solution
Shows
summary
information
and allows a
variety of
display
options
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
31
Map with site names
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
32
Demand map
Height
proportional
to demand
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
33
And coverage map
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
34
Map tradeoff solutions
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
35
Highlight solution to show
Highlight
solution to
show in top
left panel
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
36
Zoom in on a part of a solution
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
37
Exchange, delete, add sites
manually
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
38
Picking a node to add
Highlight the
node to add
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
39
For location/inventory model
Set basic inputs
Lead time
Variance to mean ratio
Z-alpha
Holding cost
Fixed order cost
Transport/inventory
weights
Local delivery cost
Days per year
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
40
Identify plant locations
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
41
And transport cost rates between
plant and DCs
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
42
Summary of basic
location/inventory costs
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
43
And inputs….
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
44
And optimal inventory policy
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
45
Map of location/inventory
solution showing plants
Plants
DCs
Markets
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
46
And finally you can quit ….
Exit SITATION
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
47
That’s all folks ….
Summer, 2010
©, M.S. Daskin, 2010, Univ. of Michigan
48