Data Analysis

[[Not yet Finished]]

Data Analysis is about

• analysis/understanding data, 
• answering questions,
• predicting what-is-going-to-happen, in short predicting future

If you're new to data analysis then you might want to take a free course at Coursera.org. It's an 8 week online course.
No specific background is needed but you must have some knowledge of basic statistic concepts such as mean, median, mode, variance, etc. and hands on experience on any programming language.
In this course R language has been used for demonstration and can be downloaded for free from CRAN.
 Here are the highlights of this course (as I go through weekly video lectures)

1. Steps in Data Analysis
• Record each step
• Define the question
• Define the  ideal data set
• Determine what data you can access
• Obtain the data
• Clean the data
• Exploratory data analysis
• Statistical prediction/modeling
• Interpret results
• Challenge results
• Synthesize/write up results
• Create reproducible code

Links to Basic Concepts - http://hbpms.blogspot.in/2008/05/stage-1-elementary-stuff.html

Things to remember at Petrol Pump

Few things that you should keep in your mind while filling petrol/diesel at any petrol pump :-

1. Don't use mobile phone - there is chance of fire. More in an article from a reliable source Why is the use of mobile phones prohibited at petrol pumps?. There several videos on youtube showing fire accidents cause because of mobile use.

2. Make sure start reading is zero - Sometimes in long queue, people are in hurry so you don't bother to check the meter reading so what happens is if person before you filled 1 Litre, the pump guy doesn't reset the meter and starts from 1 Litre only and you loose that quantity of fuel.

3. Keep an constant eye on machine till the end reading - I've experienced lot of times petrol pump guys trying to distract you from observing machine reading by asking money, etc. so that they can just reset the meter reading and get away with less fuel what we pay for.

  Once it happened with me when I was filling for Rs.200 (at Indian Oil Petrol Pump Koramangala Bangalore), till Rs.86 I was observing continuously then a person from backside asks for money and within 5-6 seconds the filling was done which I think wasn't possible and moreover the reading was not at final point as he had reset the meter. But unfortunately I didn't know how to prove it. For such cases I'm trying to find if it's feasible to check last reading.

4. Count the change returned - Mostly people fill for Rs. 100 or 200 and give Rs.500 or Rs.1000 note. Sometimes petrol pump guy doesn't return rest amount correctly. 

  Once when I filled Rs. 200 petrol (at HP Petrol Pump Koramangala Bangalore) I gave Rs.500 note, at that time I noticed the guy counting 3 x Rs.100 so I didn't count myself, kept returned amount in my shirt pocket and returned to my house. When I pulled money from my shirt pocket I found only Rs.200. At that time I thought I might have misplaced as I had gone to other shops also. Next time, I was more careful and same incident happened so I counted at petrol pump only and again 1 note was less so I asked the guy that you've not returned correct amount and he gave 1 more note making faces. Although you'll see that petrol pump guy count correct number of notes but while giving he tricks and returns less number of notes.

Similar case posted here.