Productive Access, Inc.Survey Analysis Software Solutions

Quartile Formats

mTAB™ has always allowed users to ask for descriptive statistical measures such as the Mean, Median and Standard Deviation. The Mean allows users to obtain an average value, where all responses are summed and then divided by the number of respondents  The Standard Deviation is a measure which gives an understanding of how widely spread data is around the mean value and the Median tells us the Mid-Point of a data range i.e. if all the responses to a question were put in numerical order, what would be the middle value.

The Median is a particularly good measure to use when looking at numerical questions where there are no real upper and lower limits, for example an Income question  As the Median only takes the mid-point, it can not be influenced by outliers in your dataset, for example where you have a few respondents with abnormally high or low income values  If these respondents exist, your Mean value could be pushed artificially high or low.

To enhance your understanding of the spread of data in a question such as Income, it is now possible to calculate the Upper and Lower Quartiles  As the Median is the mid-point, we can agree that it is highlighting where 50% of all respondents fall above and 50% fall below a particular point  To extend this theory, the Upper Quartile shows you the point where 75% of respondents are below and 25% are above and therefore the Lower Quartile shows you the point where 25% of respondents are below and 75% are above.

New Format Style Dialog

Creating the New Format
To obtain the Quartiles in mTAB™, we need to create a new format using the Format Style Editor  

To create a new format bring up the rows view on the right hand side of mTAB™ and select the Format Style icon or alternatively, right click your mouse and select Format Styles.  

Choose the 3rd button down on the right hand side, labelled NEW to build a new format.

 

 

 

 

 

 

 

New Format Style Dialog

The next step is to choose a format style which can be used as the basis of the new format, Median seems to be a logical choice in this example.  

We now need to add the Quartiles to this format  We can do this by clicking on the blue + next to Statistics and this category will expand.  

Now simply double click Lower Quartile and Upper Quartile and they will be added to the top box on the right hand side of the screen  

To tidy up how the data will be displayed in the spreadsheet when using this format, drag the Lower Quartile and Upper Quartile around until they fall either side of the Median value.  

Now give the format style a name, such as "Median and Quartiles" as shown.

Press the OK button and the format will be added to the question selection view toolbar listing of available formats.

Selecting the New Format
With the column banner questions highlighted, pull down the available formats toolbar menu as shown below and select our newly created format.

Format Selection Window

When the new format is now selected on a question such as Income, results similar to those displayed below will appear in the spreadsheet.

 View Larger Image

Please note that you can repeat the above process to add the Quartiles as a Column format, simply ensure you have the column window on the right hand side of mTAB™ before choosing the Format styles option.

Quartile Formats