IBM Cognos 8 Report Studio Cookbook

I received a free copy of this book in order to write my standpoint on it.

I think if you are new to cognos, or if you worked with Microsoft SQL Server Reporting Services, and want to migrate to cognos this book is very nice to follow.

Indeed, it makes the learning of cognos easier by providing lots of examples which are describes with lots of pictures.

Honestly, I think if you are professional in one reporting tools, you don't need any book, and you can just surf the tool and follow the help to overcome its difficulties.

By the way, if you are not a guru on any reporting tools, or if you do not have enough time to spend on the cognos to migrate from SSRS, I strongly recommend this book.

This book is not going to introduce any concept or any sophesticated techniques on reporting. However, it provides easy to follow step by step instructions to get familiar with the IBM Cognos 8 Report Studio.

Book Link

Solving previous problem

If we analyze the previous problem, we could consider that there are three decisions that the decision maker could take:

1. No treatment
   
2. Treatment with aspirin
   
3. Treatment with warfarin

So, we should draw a decision three with these three decisions at first branch of tree.
There are three different uncertainties that could appear for treatments. Tow of these three is applied also for no treatment.
If we draw the decision three it should looks like the following pictures. (I just provide two pictures, because the tree for treatment with warfarin is the same as the aspirin, just different valuse)






If we calculate the Expected Value (EV, which clarifies the best decision that we could make) it will be clear that patients should be treated with warfarin.

A decision tree of the problem is given at the end of this document.
No treatment & CVA & affected = ‐158,000 SEK
No treatment & CVA & unaffected = ‐76,600 SEK
No treatment & No CVA = 0
Aspirin/Warfarin & side‐effect & CVA & affected = ‐(15,000+158,000) = ‐173,000 SEK
Aspirin/Warfarin & side‐effect & CVA & unaffected = ‐(15,000+76,600) = ‐91,600 SEK
Aspirin/Warfarin & side‐effect & haemorrhage = ‐(15,000+32,000) = ‐47,000 SEK
Aspirin/Warfarin & no side‐effect & CVA & affected = ‐(15,000+158,000) = ‐173,000 SEK
Aspirin/Warfarin & no side‐effect & CVA & unaffected = ‐(15,000+76,600) = ‐91,600 SEK
Aspirin/Warfarin & no side‐effect & No CVA = ‐15,000 SEK
Folding back the tree:
EMV(no treatment) =( 0.25*(‐158,000) + 0.75*(‐76,600))*0.8 = ‐77,560
EMV(aspirin treatment) =(((( 0.25*(‐173,000)+0.75*(‐91,600))*0.644)+0.356*(‐47,000))*0.048) + (((0.25*(‐173,000)+0.75*(‐91,600))*0.5)+0.5*(‐15,000))*0.952 = ‐64,692
EMV(warfarin treatment) = (((0.25*(‐173,000)+0.75*(‐91,600))*0.5)+0.5*(‐47,000))*0.072 + (((0.25*(‐173,000)+0.75*(‐91,600))*0.1)+0.9*(‐15,000))*0.928 = ‐28,639
Thus, if we merely look at the costs for the hospital, patients should be treated with warfarin.

These kind of analysis are called subjective analysis. If you are interested to deal with these kind of problem, I recommend the Making Hard Decisions: An Introduction to Decision Analysis book by Robert T. Clemen.

Decision Tree

I hade a course previous quarter. It was about how to use decision tree for taking correct decisions. It was very amazing and I want to rewrite one of the question of final exam for showing the types of question that decision tree could help us to solve. This quarter I have the second and advance version of that course called Decision and Risk Analysis, second course.

You are working as a medical advisor at a big hospital and your department is specialized within cardiology. Your manager has asked you to formally analyze the medical condition of atrial fibrillation. In the analysis you will merely look at costs for the hospital and not consider other criteria. Atrial fibrillation is a common condition, which carries with it a significant risk for stroke (80%) if left untreated. Treatment with the medicines warfarin or aspirin significantly reduces this risk, but there are side-effects to both treatments. For the average patient (at moderate risk), treatment with aspirin has a slightly smaller risk for side-effects than warfarin, 4.8% as opposed to 7.2%, but aspirin reduces the risk for stroke less effectively than warfarin. The serious side-effects are either cerebrovascular accident, CVA during the treatment or haemorrhage. Of patients treated with aspirin and affected by side-effects, 64.4% get during their treatment, whereas this number is only 50% for patients treated with warfarin and affected by side-effects.

For the patients who do not suffer from immediate side-effects during the aspirin treatment, the risk for CVA is still 50%, whereas the risk for CVA is only 10% for patients treated by warfarin and not suffering from side-effects during the period of treatment. If an average patient (moderate risk) with atrial fibrillation gets a stroke (CVA), regardless of treatment or no treatment, he or she is classified as affected or unaffected. Out of all CVA:s that occur, 25% are affected and 75% are unaffected. Transition costs(those that happen just once) for the treatment of a patient with CVA is established to 76,600 SEK (unaffected patients), whereas the state costs (those that remain patients for their Iifetime) for treatment of a patient with CVA is estimated to 158,000SEK (affected patients). The treatment of a haemorrhage is estimated to 32,000 SEK, and the cost of a medical treatment (either aspirin or warfarin) is 15,000 SEK.

What would be your recommendation to the hospital in the handling of moderate risk patients with atrial fibrillation and why?

But how could we solve it?

If you draw the decision tree, you will see that the warfarin is the best medical treatment.

Predictable Changes with Multiple Version Overlays

There is a technique in Kimball's "Data Warehouse toolkit 2nd" book that is suggested for Predictable Changes with Multiple Version Overlays situations. It was a bit intangible for me what Kimball means for that solution, but I could understand the technique when I give another example to myself ;)

Imagine that we offer variety of products with different categories. Each product could just be belong to one category, and the category of products could be changed at the beginning of each year. However, the category of products could be changed by CEO over the time. It is ok if we want to use Slowly Changing Dimension 2 (SCD2) for this example, but the business requirements that I mention as the following make it impossible to consider this dimension as SCD2.

Imagine we need to answer these questions:

1. What is the sale of a category over a period of time? (This is not the case that makes it impossible to consider the dimension as SCD2)
2. What is the sale of the selected category in question one on the next two years? (This is a real trouble)

It may be a bit vague, so I am going to explain second question. Imagine the sales of category 1 in 2002 is X. Analysts may be interested to know what is the sale of category 1, with the products at the time of question 1, in another period of time. We should consider this fact that some category of products is changed over time; hence, how could it be possible to reflect this information.

This is the situation that we must follow what Kimball says. Consider a column for category of each year in product dimension table.

Product D
------------------
ProductID
…
Category 2001
Category 2002
Category 2003
…

I hope I could explain the situation well. I am eager to know what you think about this technique as well ;)

Second Year Blogging Anniversary

It has been always one of my concerns that I haven’t written any post here since May 14, 2009. The second year of my blog’s lifetime has only four posts that I am very sorry for that. It was occurred because I was too busy with my job and with handling application process of some universities simultaneously.
I want to start my master degree in this year to expand my knowledge about Business Intelligence. Therefore, I resigned from my job to go to Sweden. I think I will write more posts in the following year, and I hope to have wonderful experience about living in another country. I will write about the program soon ;)

The Data Model Resource Book volume 3

Sometimes I spent lots of time for finding the best way to design an ideal data model that could be comprehensive enough to cover all the prospective needs. But you couldn't always do your best, because your knowledge is depends on our experience.
It was previous week that I was looking at lots of books in Tehran Book fair. When I was looking at Wiley's books, a book grabbed my attention suddenly. It looked like a book that I have always been looking for. I believe The Data Model Resource Book volume 3 is a must book that a person who is in charge of database designing or data warehouse designing must have read.
I strongly recommend this book to all my friends who love database designing and data warehousing.
See table of contents and more details about it at Amazon.

Business Intelligence 2.0

Business Intelligence which consists of Dashboard Systems and Decision Support Systems has grown up during long time. Most systems that BI developers have been developed are belonging to Dashboard Systems which are used for demonstrating KPIs and revealing what has happened before. Decision Support Systems which are very depends on using Data Mining advantages for being implemented, have developed much fewer than Dashboard Systems.

BI 2.0 not only focuses on these systems, but it also changes the ETL way that we used to. Developing more Service oriented Applications, and the fact of having service-oriented data sources will change the way that we are using for gathering and cleaning data. Moreover, the needs of considering Business Processes and Business Rules, which exist in BPEL and BRMS, for performing ETL process would change this industry a lot.

I think the next generation of BI has a lot of challenges which are very interesting to study.