🧭Business Intelligence: Perspectives (Part 32: Data Storytelling in Visualizations)

Business Intelligence Series

From data-related professionals to book authors on data visualization topics, there are many voices that require from any visualization to tell a story, respectively to conform to storytelling principles and best practices, and this independently of the environment or context in which the respective artifacts are considered. The need for data visualizations to tell a story may be entitled, though in business setups the data, its focus and context change continuously with the communication means, objectives, and at least from this perspective one can question storytelling’s hard requirement.

Data storytelling can be defined as "a structured approach for communicating data insights using narrative elements and explanatory visuals" [1]. Usually, this supposes the establishment of a context, respectively a fundament on which further facts, suppositions, findings, arguments, (conceptual) models, visualizations and other elements can be based upon. Stories help to focus the audience on the intended messages, they connect and eventually resonate with the audience, facilitate the retaining of information and understanding the chain of implications the decisions in scope have, respectively persuade and influence, when needed.

Conversely, besides the fact that it takes time and effort to prepare stories and the afferent content (presentations, manually created visualizations, documentation), expecting each meeting to be a storytelling session can rapidly become a nuisance for the auditorium as well for the presenters. Like in any value-generating process, one should ask where the value in storytelling is based on data visualizations and the effort involved, or whether the effort can be better invested in other areas.

In many scenarios, requesting from a dashboard to tell a story is an entitled requirement given that many dashboards look like a random combination of visuals and data whose relationship and meaning can be difficult to grasp and put into a plausible narrative, even if they are based on the same set of data. Data visualizations of any type should have an intentional well-structured design that facilitates visual elements’ navigation, understanding facts’ retention, respectively resonate with the auditorium.

It’s questionable whether such practices can be implemented in a consistent and meaningful manner, especially when rich navigation features across multiple visuals are available for users to look at data from different perspectives. In such scenarios the identification of cases that require attention and the associations existing between well-established factors help in the discovery process.

Often, it feels like visuals were arranged aleatorily in the page or that there’s no apparent connection between them, which makes the navigation and understanding more challenging. For depicting a story, there must be a logical sequencing of the various visualizations displayed in the dashboards or reports, especially when visuals’ arrangement doesn’t reflect the typical navigation of the visuals or when the facts need a certain sequencing that facilitates understanding. Moreover, the sequencing doesn’t need to be linear but have a clear start and end that encompasses everything in between.

Storytelling works well in setups in which something is presented as the basis for one-time or limited in scope sessions like decision-making, fact-checking, awareness raising and other types of similar communication. However, when building solutions for business monitoring and data exploration, there can be multiple stories or no story worth telling, at least not for the predefined scope. Even if one can zoom in or out, respectively rearrange the visuals and add others to highlight the stories encompassed, the value added by taking the information out of the dashboards and performing such actions can be often neglected to the degree that it doesn’t pay off. A certain consistency, discipline and acumen is needed then for focusing on the important aspects and ignoring thus the nonessential. 

Previous Post <<||>> Next Post

References:
[1] Brent Dykes, "Effective Data Storytelling: How to Drive Change with Data, Narrative and Visuals", 2019 [quotes]

🧭Business Intelligence: Perspectives (Part 26: Monitoring - A Cockpit View)

Business Intelligence Series

The monitoring of business imperatives is sometimes compared metaphorically with piloting an airplane, where pilots look at the cockpit instruments to verify whether everything is under control and the flight ensues according to the expectations. The use of a cockpit is supported by the fact that an airplane is an almost "closed" system in which the components were developed under strict requirements and tested thoroughly under specific technical conditions. Many instruments were engineered and evolved over decades to operate as such. The processes are standardized, inputs and outputs are under strict control, otherwise the whole edifice would crumble under its own complexity. 

In organizational setups, a similar approach is attempted for monitoring the most important aspects of a business. A few dashboards and reports are thus built to monitor and control what’s happening in the areas which were identified as critical for the organization. The various gauges and other visuals were designed to provide similar perspectives as the ones provided by an airplane’s cockpit. At first sight the cockpit metaphor makes sense, though at careful analysis, there are major differences. 

Probably, the main difference is that businesses don’t necessarily have standardized processes that were brought under control (and thus have variation). Secondly, the data used doesn’t necessarily have the needed quality and occasionally isn’t fit for use in the business processes, including supporting processes like reporting or decision making. Thirdly, are high the chances that the monitoring within the BI infrastructures doesn’t address the critical aspects of the business, at least not at the needed level of focus, detail or frequency. The interplay between these three main aspects can lead to complex issues and a muddy ground for a business to build a stable edifice upon. 

The comparison with airplanes’ cockpit was chosen because the number of instruments available for monitoring is somewhat comparable with the number of visuals existing in an organization. In contrast, autos have a smaller number of controls simple enough to help the one(s) sitting in the cockpit. A car’s monitoring capabilities can probably reflect the needs of single departments or teams, though each unit needs its own gauges with specific business focus. The parallel is however limited because the areas of focus in organizations can change and shift in other directions, some topics may have a periodic character while others can regain momentum after a long time. 

There are further important aspects. At high level, the expectation is for software products and processes, including the ones related to BI topics, to have the same stability and quality as the mass production of automobiles, airplanes or other artifacts that have similar complexity and manufacturing characteristics. Even if the design process of software and manufacturing may share many characteristics, the similar aspects diverge as soon as the production processes start, respectively progress, and these are the areas where the most differences lie. Starting from the requirements and ending with the overall goals, everything resembles the characteristics of quick shifting sands on which is challenging to build any stabile edifice.

At micro level in manufacturing each piece was carefully designed and produced according to a set of characteristics that were proved to work. Everything must fit perfectly in the grand design and there are many tests and steps to make sure that happens. To some degree the same is attempted when building software products, though the processes break along the way with the many changes attempted, with the many cost, time and quality constraints. At some point the overall complexity kicks back; it might be still manageable though the overall effort is higher than what organizations bargained for. 

Previous Post <<||>> Next Post

⚡️🗒️Power BI: Working with Visual Calculations (Part I: Test Drive) 🆕

Introduction

I recently watched a webcast with Jeroen (Jay) ter Heerdt (see [2]) in which he introduces visual calculations, a type of DAX calculation that's defined and executed directly on a visual [1]. Visual calculations provide an approach of treating a set of data much like an Excel table, allowing to refer to any field available on a visual and write formulas, which simplifies considerably the solutions used currently for ranking records, running averages and other windowing functions. 

The records behind a visual can be mentally represented as a matrix, while the visual calculations can refer to any column from the matrix, allowing to add new columns and include the respective columns in further calculations. Moreover, if a column is used in a formula, it's not recalculated as is the case of measures, which should improve the performance of DAX formulas considerably. 

Currently, one can copy a formula between visuals and if the formula contains fields not available in the targeted visual, they are added as well. Conversely, it's possible to build such a visual, copy it and then replace the dimension on which the analysis is made (e.g. Customer with Product), without being needed to make further changes. Unfortunately, there are also downsides: (1) the calculations are visible only within the visual in which were defined; (2) currently, the visual's data can't be exported if a visual calculation is added; (3) no formatting is supported, etc.

Ranking and Differences

I started to build a solution based on publicly available sales data, which offers a good basis for testing the use of visual calculations. Based on a Power BI visual table made of [Customer Name], [Sales Amount], [Revenue] and [Total Discount], I've added several calculations:

-- percentages
Sales % = 100*DIVIDE([Sales Amount], COLLAPSE([Sales Amount], ROWS))
Revenue % = 100*DIVIDE([Revenue],[Sales Amount])
Discount % = 100*DIVIDE([Total  Discount], [Total  Discount]+[Sales Amount])

-- rankings 
Rank Sales = Rank(DENSE, ORDERBY([Sales Amount], DESC))
Rank Revenue = Rank(DENSE, ORDERBY([Revenue], DESC))

-- differences between consecutive values
Diff. to Prev. Sales = IF([Rank Sales]>1, INDEX([Rank Sales]-1, , ORDERBY([Sales Amount], DESC)) - [Sales Amount] , BLANK())
Diff. to Prev. Rev. = IF([Rank Revenue]>1, INDEX([Rank Revenue]-1, , ORDERBY([Revenue], DESC)) - [Revenue] , BLANK())

Here's the output considered only for the first 10 records sorted by [Sales Amount]:

Customer Name	Sales Amount	Sales %	Revenue	Revenue %	Total Discount	Discount %	Rank Sales	Diff. to Prev. Sales.	Rank Rev.	Diff. to Prev. Rev.
Medline	1058923.78	3.76	307761.99	3.75	126601.02	10.68	1		1
Ei	707663.21	2.51	229866.98	2.8	95124.09	11.85	2	351260.57	2	77895.01
Elorac, Corp	702911.91	2.49	209078.76	2.55	83192.39	10.58	3	4751.3	6	20788.22
Sundial	694918.98	2.47	213362.1	2.6	78401.72	10.14	4	7992.93	4	-4283.34
OUR Ltd	691687.4	2.45	196396.26	2.4	78732.2	10.22	5	3231.58	10	16965.84
Eminence Corp	681612.78	2.42	213002.78	2.6	86904.03	11.31	6	10074.62	5	-16606.52
Apotheca, Ltd	667283.99	2.37	157435.56	1.92	101453.91	13.2	7	14328.79	31	55567.22
Rochester Ltd	662943.9	2.35	224918.2	2.74	81158.11	10.91	8	4340.09	3	-67482.64
ETUDE Ltd	658370.48	2.34	205432.79	2.51	89322.72	11.95	9	4573.42	9	19485.41
Llorens Ltd	646779.31	2.29	206567.4	2.52	82897.59	11.36	10	11591.17	8	-1134.61

Comments:
1) One could use [Total Amount] = [Total  Discount]+[Sales Amount] as a separate column.
2) The [Rank Sales] is different from the [Rank Rev.] because of the discount applied.
3) In the last two formulas a blank was considered for the first item from the ranking.
4) It's not possible to control when the totals should be displayed, however one can change the color for the not needed total to match the background.

Visualizing Differences 

Once the formulas are added, one can hide the basis columns and visualize the data as needed. To obtain the below chart I copied the visual and changed the column as follows:

Diff. to Prev. Rev. = IF([Rank Revenue]>1, [Revenue]- INDEX([Rank Revenue]-1, , ORDERBY([Revenue], DESC)) , [Revenue]) -- modified column

Comments:

1) Instead of showing the full revenue, the chart shows only the differences from the highest revenue, where the column in green is the highest revenue, while the columns in red are the differences of the current customer's revenue to the previous customer, as the data are sorted by the highest revenue. At least in this case it results in a lower data-ink ratio (see Tufte).

2) The values are sorted by the [Revenue] descending. 

3) Unfortunately, it's not possible to change the names from the legend.

Simple Moving Averages (SMAs)

Based on the [Sales Amount], [Revenue] and [Month] one can add the following DAX formulas to the table for calculating the SMA:

Sales Amount (SMA) = MOVINGAVERAGE([Sales Amount],6)
Revenue (SMA) = MOVINGAVERAGE([Revenue],6)

The chart becomes:

Comments:

1) Unfortunately, the formula can't project the values into the feature, at least not without the proper dates.
2) "Show items with not data" feature seems to be disabled when visual calculations are used.

3) The SMA was created via a template formula. Similarly, calculating a running sum is reduced to applying a formula:

Running Sales Amount = RUNNINGSUM([Sales Amount])

Wrap Up

It's easier to start with a table for the visual, construct the needed formulas and then use the proper visual while eliminating the not needed fields. 

The feature is still in public preview and changes can still occur. Unfortunately, there's still no information available on the general availability date. From the first tests, it provides considerable power with a minimum of effort, which is great! I don't want to think how long I would have needed to obtain the same results without it!

Happy coding!

Previous Post <<||>> Next Post

References: 
[1] Microsoft Learn (2024) Power BI: Using visual calculations [preview] (link)
[2] SSBI Central (2024) Visual Calculations - Making DAX easier, with Jeroen ter Heerdt (link)