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Showing posts from December, 2010

### Probability - And Business Decisions!

Studying statistics is an interesting endeavor as business activities are so closely related to observation, formulation of strategies and extrapolation for analysis of data and implementation of new strategies. The behavior of large groups of people can be as random as coin tosses as mentioned in the previous post. In fact the entire life insurance business is based on this fact. We can't predict whether a specific person will die next year (except for my mother who can predict deaths through dreams...no pun intended she seriously can.) But if we observe millions of people, deaths are random. Hence make accurate prediction models for payouts. The proportion of men aged 25 to 34 who will dice next year is about 0.0021 say on the North American continent. When you have this data compared to the probability of death in women which about 0.0007 for the same range an insurance company tat sells many policies to people aged 25 to 345  will have to pay off on about 0.21% of the polices…

### Randomness & Probability

The idea of probability is empirical. I chuckled when I twittered last night on Einstein's quote that- "God does not care about our mathematical difficulties. He integrates empirically". So probability is the art of observing a class of data closely and describing the data in several trials. Hence Randomness or "Random" behavior in statistics is not a synonym for "haphazard" but a description of a kind of order that emerges only in the long run.

The French naturalist Count Buffon (1707 - 1788) tossed a coin 4040 times. The results were 2048 times heads which means 0.5069 chances for the heads to occur. Around 1900 Karl Pearson heroically tossed the coin 24,000 times result was 12,012 heads, a proportion of 0.5005. John Kerrich while imprisoned in the German Nazi camp tossed the coin 10,000 times the result of which was 5076 heads, a proportion of 0.5067. So to make a point about randomness and probability we call a phenomenon random if individual outc…

### Creating Value with Assets & Services

A lot of talk floats around of creating IT as a strategic component when 60% of its activities are service or support related. The art of IT alignment with proper governance wrapped around them not only makes IT a strategic component but enables its support functions to add value to business assets and services. In some instances values can be quantified in financial terms and in some non-financial terms. The non-financial terms are equally important as they fuel the financial components on a continuous form of inputs or future ROI's and VOI's. These non-financial value creation ideas can be:

1) Customer Perceptions: Customer's preferences are influenced by perceptions and in turn perceptions are influenced by attributes of a service or product in terms of value, desire, previous experience, position in the marketplace, need and self-image.

2) Reference values of services: This may be very vaguely defined and sometimes may be plain facts. To find our reference value of ser…

### The Expanding Universe

Thinking about regression, I came across Edwin Hubble's data in the Astronomy magazine and found out that the scatter-plot of the data Hubble gave played a central role in the discovery that universe is expanding. The graph below shows the distances from earth of 24 spiral galaxies, just for kicks I plotted this in excel, the speed indicates the speed at which these galaxies are moving away from us as reported in 1929 by Hubble's data.

The scatter-plot clearly indicates a linear relationship my TI-83 reports a r=0.7842 correlation which means that distant galaxies are moving away rapidly. Astronomers believe that there is a perfect linear relationship along with the scatter caused by imperfect measurements. The two lines on the plot are actually the two-least squares regression lines. The regression line of velocity on distance is solid as indicated. The regression line if drawn of distance on velocity will be different and both lines will have different slopes.

Lesson learnt …

### Statistical Thinking - Regression?

Regress means to go backward. How did the term regression come to be? Sir Francis Glaton (1822-1911)  was the first one to apply regression techniques on biological and psychological data. He observed data in heights of tall parents and found that often taller than average parents tended to have children who were also taller than average but not as tall as their parents. Galton called this fact "regression" toward the mean and the name came to be applied to statistical method.

A regression line is very important measure in research then because a regression line summarizes the relationship between independent and dependent variables. as in specific settings one of the variables helps explaining or predicting the other.

Why am I relating this here? I remember a year I talked about visual mapping with mind map, certainly our brain does not always think in linear fashion, thoughts, ideas projects, to do's, likes, dislikes, desires, passions, etc are all over the place. So t…