smarter Dimensions

How to use MDMExplorer

Sunday, December 7th, 2008 | Tools

 There are a few tools that you should always be using to help you with your Dimensions work this article is about the tool “MDM Explorer”. MDMExplorer helps you look in detail at Metadata Documents ( MDD ). It will show you all the collections and properties of an MDD file and allow you to change some of the values stored in it. The MDM Explorer tool comes with the Dimensions development library and if you have this installed you can find it in the following directory.

C:\Program Files\SPSS Dimensions\DDL\Code\Tools\VB6\MDM Explorer

It is probably better to put an icon on your desktop of MDMExplorer because as you become familiar with the datamodel the more you will use this tool.  At this stage I would also like to add that there are two other tools that you should look at , and they are

How to use DMQuery
How to use Windmsrun

So once we have an icon on our desktop, double click it and you should see a screen like this.

MDMExplorer is used to connect to MDD or Meta Data Documents however it is also used to create MDD files. If you look of the file menu you will see we have two “open” options, they are described as follows

Open MDSC:  This option is used when you don’t have an MDD file, if you click “File” then “Open MDSC” you will see the following screen

open mdsc

 

 

When you explore the “File Types” dropdown you will see that we have an option for every read metadata DSC the datamodel has available, specify the type you want to use and then find the metadata file you want to open, select it and the click “Open”. We now have an MDD in memory so what we need to do next is to click “File” then “Save As” and you will then be prompted to save your MDD file.

Open Document: This option is used to open a MDD or Metadata Document that already exists, click “File” and the “Open Document” this will then load an MDD in, depending on the size of the MDD will depend on how long it takes to finish loading, in this example we have loaded the museum MDD file that can be found in the following directory.

C:\Program Files\SPSS Dimensions\DDL\Data\Dimensions File

Once you have loaded the MDD you should see the follow

As we can see from the image the screen is split into three areas, the first area on the right is a list of all the collections in the MDD file. From this you should be able to see that an MDD file is not just the questions and the logic it is much much more, later on in this article we will go through each collection and talk about what they hold. The next area is the properties / values area, when you click something in the collections list you will see its properties and their values, as you click on items in this area, underneath it you will see just the value appear. This third area is where we can modify and edit the values. The key to editing the values is to make sure that when you have made the change that you click the  apply button which you will find on the bottom right hand side of the screen.

Next we will look at all the collection and briefly describe them. As time goes on we will write an article on each collection explaining it in more detail.

 

Collection Name:	Brief Description:
Labels	Most objects in an MDD have a label property, the labels collection allows you to see what labels are available for you object, the label Text is broken down to the Language and Context level.
Versions	It is possible to have multiple versions in your MDD, what this means is that as you create your MDD file and depending on what tool you use to create it and depending on what you do with it will depend on how versions get added. It is important to keep track of versions and you should always try and “GO LIVE” with version one of your MDD file.
Fields	This is the list of all your questions, you will also see that the MDD has some System fields in it that will be used to collect system information and help you track your data.
Items	When you expand this collection you will see everything that you see when you expand Fields, Helperfields, Pages and Types collections. With every thing found in one place allows you to easily scan one list to find what you are looking.
Pages	For display purposes It is possible to display multiple questions on a screen or page, and in a survey it is possible to have multiple pages. The pages collection allows you to store this information.
Variable Instances	The Variable Instances collection provides us with a list of all the data slots in a single respondents record. These are the field names that we will see when we do a “select * from vdata” on our data in something like DMQuery.
Types	When we expand this collection we see a list of template objects in the Document. These objects can be re-used; for example, a define or shared list you would create a reference to it, rather than defining it a second time.
Languages	It is possible to have multiple languages in the same MDD, labels are created to store the different texts used to represent the different words used in each available language.
Contexts	It is possible to have different collection modes in your MDD, for instance you could have one survey that is used for CATI and ONLINE. If we had these two modes the words used by the interviewer for a CATI survey would be different for ONLINE survey. Contexts are used to help manage this type of addition customization if required.
Label Types	LabelTypes are used to define different types of texts. For example, Label (the default) used for question texts and variable descriptions, Shortname, Instruction, etc. Expanding this collection will show you what label types you have available to store information in.
Routing Contexts	When you create a survey you can ask questions in different orders depending on the mode that you are using. This collection will show you what contexts have been created , e.g. Paper, CATI and Web
Script Types	Expanding this collection show us the Scriptypes that have been used in the MDD , at this stage there is only one script type used so you should just see “mrScriptBasic”
Routing	This collection is used to manage the multiple routings you can have in a survey. For example in CATI you may want to ask Questions in a different order than you would in the online version of your survey.
Data Sources	If you expand this collection you will see a list of all the dscs that have been used to connect to case data associated with this MDD.
Category Map	As you add responses to your mdd file they will be assigned a unique number. This collection controls the number and is the number that you see when you query the data and see something like {45}
AliasMap	When you create variable names , there are some rules that you have to follow. There rules are managed by the Alias Map Generator and if you want you can change them then the new rules that you create will be stored in this collection.
Custom Properties	When using the datamodel it is possible to add addition and custom properties to almost all of the objects, this collection is a list of all the properties that someone has added to the MDD object itself.
Custom Properties (Datasources)	This is a collection that can be used to store the custom properties associated with the DSC’s that you may be using.
Levels	This collection shows you all the different data levels. A level is like a loop within a loop, you have the outer loop which is the top level and the inner loop is the bottom level. It is possible , and common to have multiple level data. You can see this data represented when you do a “Select * from HDATA” in something like DMQuery.
Selected Versions	This collection shows us the currently selected versions.
VersionSets	We have seen that as we build our survey we can have multiple versions, version sets are groupings of these versions, for example we may want to see all the results collected for a particular question but only across versions { 2,7,10} of the survey. If this group was something we used allot we could store this grouping in this collection.
SaveLogs	An object containing logging information to be written to an MDM document when changes to an .mdd file are saved.
Templates	This collection gives us the full list of templates used in the MDM document. Templates allow users to present objects to the interview is run.
Notes	This collection when expanded shows the notes collection, this contains user comments that are displayed in an mrScriptMetadata script when the metadata document (.mdm) file is opened in an authoring tool such as mrStudio.

Now we have some understanding  of what we can find when using MDMExplorer we will leave it up to you to tell us what you want to know next, leave a comment on this article and we will see if we can provide more information. As you work with Dimensions you will find a need to use this tool, and hopefully we have just given you enough information to get started.

2 Comments to How to use MDMExplorer

Leave a comment