Tag Archives: Lecturer

A very interesting student work from my business statistics class

This is a very interesting presentation as the final exam of my “Business statistics” class at Yokohama National University in Japan.


My classes are all for international students and this is work of a student from Vietnam.

The students learned how to set a practical goal and how to effectively use some analytical techniques to support the conclusion(s).

The student tried to find out the difference of the students from two different countries, Vietnam and Japanese in terms of GPA and objectives to learn at university.


While the sample size is small and the conclusions are not necessarily surprising, the approach and analysis itself was quite interesting.


My class is not just to teach some academic analytical techniques but to teach how to apply those techniques to meet practical goals.

I would be happy to give my lecture anywhere in the world.


Hana 1Hana 2Hana 3Hana 4Hana 5


Launched “Data&Story” website in English

The new website in English has just been opened for English-speaking customers.

As I have some classes in English at Yokohama National University, I am always welcome clients who want “business data analysis(Excel-based)”, ” problem-solving” programs taken place in English.

You can try those programs either in Japan or any other countries.



My programs are all practical based on my 20 year experience at Hitachi and Nissan.

My clients are large organization which have issues to develop basic business skills in new business development, marketing, sales, administration etc.

While they have huge data and systems, they really do not have human skills to manage those technologies/data. My programs will help you have practical skills to make the most of your business assets.

The human skills will change your organization to be even more competitive with data analysis and logical problem-solving skills.

For more detail, please visit the site and please feel free to ask any questions if any.



Six questions to check the data utilization in your organization

1. Can you oversee your entire business performance, including outside of your view? YES/NO?

2. Can you explain the current business situations to others in an objective way? YES/NO?

3. Can you identify the root-cause of a problem(s) when happening, not just relying on what you physically see? YES/NO?

4. Can you evaluate the performance of your operations/business with appropriate indicators(KPIs)? YES/NO?

5. Can you connect the evaluation and actions in an effective and logical way? YES/NO?

6. Can you systematically respond to the changes in the markets and estimate the impact to your business, not just following your past experience? YES/NO?

The number of “YES” out of the six questions indicates your organization’s data utilization and data literacy.

What you need to consider when drilling down the data.(vol.2)

There is always a gap between theory and reality.

A theoretically correct idea is not necessarily a right answer in reality. You may observe the same issue in the data analysis.

When you drill down or breakdown a set of data by some axis (age, area, product etc.), you may come up with lots of options of axis. Even if it is theoretically possible, I would suggest that you should make sure that the axis you select will lead to some effective action(s).

For example, if you try to categorize the sales results by the weather (sunny, rainy or cloudy), you may able to technically do it. But it would not help you determine the actions you take for sales improvement because you cannot control the weather anyway.

If you use some axis by which you drill down some data, you may consider whether the axis is actionable or not. This is extremely important from the practical viewpoints.

If you select “age” axis for your analysis, then you may reach some actionable ideas on how to improve the sales from a certain category of age( eg. 20’s).

In business, “actionable” is always a priority.

the axis.

Final session of “Modeling with statistics” class

It was the last session of my class today at Yokohama National University.

The final exam report was announced with the following requirements:


It was extremely wonderful experience to me and it was really fun!

My goal of this class has been how to solve real and practical issues in business, by developing a logical story with data (analysis).

I  the students enjoyed the class and will see them in the coming semester again for the class “Logical problem-solving”, in which I will talk about “Logical thinking to reach an agreement with stakeholders” !

I am so excited again. Please contact me if you need a lecture (one-day, short-term intensive or long-term) of decision science even outside of Japan.


From my lecture note at university #12(Modeling with statistics)

Today it was the second session for hypothetical testing.

We focused on testing a gap of two averages, which I believe is the most commonly used in practical business situations.

It was really hard to explain the concept of the statistical hypothesis testing, which is very confusing for beginners.

Concept of “Population” and “Sample” is the first one you have to understand as well as the fact that, in most cases, we are using “sample” data for data analysis.


From such academic topic, we moved to a practical topic, which is the test of two average gap between two groups.

Excel (T.TEST) function helps you to minimize your calculation to reach the conclusion as long as you understand how the testing works.


For the practical use, my advice was to focus only on the determinations on “one-tailed or two-tailed distribution” and “type of the testing”, which you have to specify in the function.


Once the class understood the concept and theory, we moved to the practical exercises.


Apart from those exercises, we tested the gap of average amounts to pay for lunch between “female” and ” male” students, by using sample data of the class.

It was really fun!

Finally this is today’s take-away.


Thank you again for enjoying my class today!