Session Logs Tutorial for SPM

How Did I Get That Model?

Session Logs in SPM

Dan Steinberg

Salford Systems

http://www.salford-systems.com

December 2012

SPM Version Numbers

• Salford Systems has begun offering SPM 7.0 to all of our

customers (as of November 30, 2012) and from this date

forward our videos and instructional materials will make use

of the SPM 7 application

• The SPM interface was designed to be as similar as

possible to the SPM 6 series of software meaning that you

can follow along for much of the presentation with that

version (or with version 6 generations of the standalone

engines

• We will clearly point out features, options, and controls that

are unique to 7

• The current video and blog is largely relevant to SPM 6 and

you will not require SPM 7 for most of its content

© Copyright Salford Systems 2012

How Did I Get That Model or Result?

• In the course of interactive data analysis modelers typically

modify many model setup controls and options

• Many modelers will also alter the data they use

– Construction of new variables during the session

– Focusing on specific subsets of the data (segments)

– Using SELECT statements or DELETE records via the built-in

Salford BASIC programming language

• After a long session of changing this and that you might find

that you have lost track of exactly what you have done

• You might not realize this until you save work and come

back to again after a long weekend or after a hiatus of

several weeks


How SPM Can Help You

• SPM and its predecessor standalone data mining products

CART, MARS, TreeNet, and RandomForests all maintain an

audit trail of every session

• The audit trail is a set of commands that were generated

either by you or by the GUI (Graphical User Interface) on

your behalf as you conducted your session

• The audit trail does not record pure GUI actions you might

have taken such as viewing the Variable Importance ranking

or resizing a window

• The audit trail records all file open and save actions and

commands that set up or run a model


The Command Log

• For the log of your current session the simplest way to

review it is to click on the command log icon on the toolbar

– The “L” circled in red below


Clicking on the “L” icon brings up a text file


Understanding the Command Log

• Often you do not need to pay any attention to most of this file as it is

devoted to setting up default options

• Instead you will want to focus on essentials such as

– USE the command connecting you to your data

– MODEL the command identifying your target

– KEEP the command listing the predictors you are using

– Here are our commands related to the setting up of a regression tree

using the BOSTON.CSV Boston housing data set


Saving and Retrieving Command Logs

• You do not have to worry about saving the command logs as they

are saved for you automatically

• However, you should make your own decision as to where your

logs will be saved

• We recommend that you to to the EDIT menu and select Options


Alternatively, select the check mark toolbar icon


This brings up the same

dialog as does the EDIT

..Options menu item

Then select the Directories

tab

Select a convenient location for Temporary Files


In addition to temporary work files we also permanently store command logs for

every session in this location.

Windows will default to a possibly awkward location so we advise changing it

SPM 7 automatically navigates to the stored logs


In version 6 applications you will need

to navigate to this location manually if

you wish to open one of the past

session logs

Select this item in SPM 7 to reveal

the log archives as shown on the next

screen

Directory Listing of Past Session Logs


These are all plain text files with a .TXT extension and have names beginning with

CTRXmmdd where mm=month and dd=date of creation. The remainder of the name is

randomly generated. Files of size 2KB are for sessions that just opened and closed SPM

Session Logs Are Permanent

• We do not ever delete session logs but you might want to

both selectively delete some sessions including the ones in

which next to nothing was done

• You might also want to rename important logs so that you

can tell what they are about

• Session logs are updated after each command is generated

either by you directly from the command line or via the

commands that the GUI generates for you

• Session logs are generally complete but may lack the very

last command issued if the application of the Operating

System subsequently crashed

• Session logs are critical for diagnosing problems as well as

for determining exactly what you did to obtain a result © Copyright Salford Systems 2012

Command Logs and Groves

• SPM stores all models in a special form we call a grove.

Groves may optionally be saved and transferred from one

machine to another including between Windows and

Linux/UNIX platforms

• Groves store model information and the entire command log

up to the point at which the model in question was

generated

• If you build three consecutive models

– The first model grove will contain the command log up to the point

that the first model was built

– The second model grove will contain the command log relevant to

both the first and the second models

– The third model grove will contain the command log for al three

models built


Command Log from GUI (Grove)


We can access all commands issued in the session up to the creation of this

model. These commands are saved in the grove file.

GUI Grove Based Command Log Display:

TreeNet Model

• If a model’s main results are being displayed you will always

see a “Commands” button towards the bottom of the display


“Commands” button is available for CART, MARS, GPS, and TreeNet models.

Reveals same information as command log up to the moment model was created

Commands available at any future time from the grove if it is saved

Hints on Trouble Shooting

• Since the command logs contain literally every command

issued either by you directly or by the GUI on your behalf it

serves as a source of information for explaining unexpected

results

• Some common causes unexpected results include

– A SELECT command being active or inactive

– BASIC commands deleting some records, setting certain predictors

to missing, or altering some predictors

– Analysis type being changed from Classification to Regression

– An active LIMIT command preventing a CART tree from growing as

large as expected or desired

– Model setup controls altered such as CART growing method or

number of nodes in TreeNet trees, etc.


Session Logs Tutorial for SPM

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