STATISTICS
INTRODUCTION
Statistics is the method of conducting a
study about a particular topic by collecting, organizing, interpreting, and
finally presenting data. Being a statistician at an elementary level may simply
mean noticing patterns in daily circumstances and drawing conclusions about
those patterns. On a grander scale, statisticians may spend months or years
conducting a study before they can produce meaningful analysis of information.
Statistics is its own community, with rules, procedures, and policies all built
on simple mathematical principles.
Stages
in the Statistical Process
The statistical process guides
genuine study, and statisticians are exacting in their methodologies. The major
steps of statistics are explained in a simplistic form as follows:
- Planning a study: There
must be a subject that requires investigation. Planning entails deciding
what instruments (interviews, surveys, etc.) to use, who to speak with,
and how to analyze findings. Instruments, in this case, are
tools used in conducting a study like surveys, interviews, etc. Do you
remember Timmy? In this stage, he plans to interview shoppers and count
people.
- Organizing the data: The
best way to obtain the valid answers is to organize the information
effectively to help expose patterns and other significant relationships.
There are a variety of software programs that can help with this step.
Once Timmy has gathered data, he could perform calculations of the mean,
mode, and median visitors.
- Interpreting the
data: This is the heartbeat of statistics. Interpretations can have
lasting repercussions, and it's important to make sure they are valid
assumptions and supported by mathematical reasoning. Timmy, based on his
interpretations of the numbers, could make plans to have special sales on
days with the most traffic.
- Presenting the data: The
methods you chose to present the data can make findings more interesting
or powerful. People use graphs, tables, and various diagrams to show
relationships between data. With this information, Timmy could present
compelling arguments using his analysis so that he and his business
partners can discuss the most profitable possibilities for the pizza shop.
Applications
of Statistics
Other than individuals and small
businesses owners like Timmy who conducted their own studies, there are some
entities who thrive on statistics. Here are a few major examples.
Government Agencies
The government uses statistics to
make decisions about populations, health, education, etc. It may conduct
research on education to check the progress of high schools students using a
specific curriculum or collect characteristic information about the population
using a census.
Statistical laws
Statistical law or (in popular terminology) a law of statistics represents a
type of behaviour that has been found across a number of datasets and, indeed,
across a range of types of data sets. Many of these observances have been
formulated and proved as statistical or probabilistic theorems and the term
"law" has been carried over to these theorems. There are other
statistical and probabilistic theorems that also have "law" as a part
of their names that have not obviously derived from empirical observations.
However, both types of "law" may be considered instances of a scientific
law in the field of statistics. What distinguishes an empirical statistical law from a
formal statistical theorem is the way these patterns simply appear in natural
distributions, without a prior theoretical reasoning about the data.
Examples
There are several such popular
"laws of statistics".
The Pareto principle is a popular example of such a "law". It
states that roughly 80% of the effects come from 20% of the causes, and is
thusly also known as the 80/20 rule. In business, the 80/20 rule says that
80% of your business comes from just 20% of your customers. In software
engineering, it's often said that 80% of the errors are caused by just 20% of
the bugs. 20% of the world creates roughly 80% of worldwide GDP. 80%
of healthcare expenses in the US are caused by 20% of the population.
Zipf's law, described as an "empirical statistical law"
of linguistics, is another example. According
to the "law", given some dataset of text, the frequency of a word is
inversely proportional to its frequency rank. In other words, the second most
common word should appear about half as often as the most common word, and the
fifth most common world would appear about once every five times the most
common word appears. However, what sets Zipf's law as an "empirical
statistical law" rather than just a theorem of linguistics is that it
applies to phenomena outside of its field, too. For example, a ranked list of
US metropolitan populations also follow Zipf's law, and even forgetting follows Zipf's law. This act of summarizing
several natural data patterns with simple rules is a defining characteristic of
these "empirical statistical laws".
Examples of empirically inspired
statistical laws that have a firm theoretical basis include:
Examples of "laws" with a
weaker foundation include:
Examples of "laws" which
are more general observations than having a theoretical background:
Examples of supposed
"laws" which are incorrect include:
APPLIED LAWS OF STATISTICS IN REAL
LIFE
You can use statistics in everyday life
in the following way.
1. Applying decision theorem in making
daily decisions by calculating probability of each decision with its likelihood
2. Using sampling method in selection
of items
3. Using transportation model in
planning your daily movement
4. Calculating the risk of taking or
not taking a decision
5. Calculate the chances of success or
failure in trying a new method using binomial distribution model etc
·
Every
time you go to an online shopping site like Flipkart or Amazon, you see the
ratings of the products, the reviews of the customers etc. All this data that
you see is nothing but statistics.
·
Every
time you go to cast your vote, you compare the performance of the current
government to that of the other previous governments. You also decide whom to
vote on the basis on the promises made by the other party leaders which often
use phrases like “We will try to improve the education rates to ……….”. All this
data is part of statistics.
·
Whenever
you are planning a trip or a journey, you take in account the weather
conditions of the place. Since future telling machines haven’t been invented
till now, all the data you see is due to the goodwill of statistics.
·
You
know that in order to drive your car you are required by law to have car
insurance. If you have a mortgage on your house, you must have it insured as
well. The rate that an insurance company charges you is based upon statistics
from all drivers or homeowners in your area.
·
Stock
market is a concept we all hear about in our day to day lives and it will not
come as a surprise to you that it is completely based on statistics as stock
analysts also use statistical computer models to forecast what is happening in
the economy.
·
Sport
selections are mostly done on the basis of data about the performance and the
form of the player. Also tin the modern world that we live in statistics of
player make the match or game more interesting and provide ground for fans to
argue about the dominance of their favorite player in the game.
REFERENCES
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Explanation. University of
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Gelbukh, A., Sidorov,G. (2008). Zipf and Heaps Laws’
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In:Computational Linguistics and Intelligent Text Processing (pp. 332–335),
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Kitcher & Salmon (2009) p.51
Bunkley, Nick (2008-03-03). "Joseph Juran, 103, Pioneer in Quality Control, Dies". The New York Times. ISSN 0362-4331. Retrieved 2017-05-05.
Rooney, Paula (2002-10-03). "Microsoft's CEO: 80-20 Rule Applies To Bugs,
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Retrieved 2017-05-05.
1992 Human Development Report. United Nations Development
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Gelbukh & Sidorov (2008)
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