Statistics is the science of collecting, organizing, and interpreting
numerical facts, which we call data. Data bombards us in everyday life.
Most of us associate statistics with the bits of data that appear in news
reports: baseball batting averages, imported car sales, the latest poll of
the president’s popularity, and the average high temperature for today.
Advertisements often claim that data show the superiority of the
advertiser’s product. All sides in public debates about economics,
education, and social policy argue from data. Yet the usefulness of
statistics goes far beyond these everyday examples.
The study and collection of data are important in the work of many
professions, so that training in the science of statistics is valuable
preparation for a variety of careers. Each month, for example, government
statistical offices release the latest numerical information on
unemployment and inflation. Economists and financial advisors as well as
policy makers in government and business study these data to make informed
decisions. Doctors must understand the origin and trustworthiness of the
data that appear in medical journals if they are to offer their patients
the most effective treatment. Politicians rely on data from polls of public
opinion. Market research data that reveal consumer tastes influence
business decisions. Farmers study data from field trials of new crop
varieties. Engineers gather data on the quality and reliability of
manufactured products. Most areas of academic study make use of numbers,
and therefore also make use of the method of statistics.
We can no more escape data than we can avoid the use of words. Just as
words on a page are meaningless to the illiterate or confusing to the
partially educated, so data do not interpret themselves but must be read
with understanding. A writer can arrange words into convincing arguments or
incoherent nonsense. Similarly, you can manipulate data to be compelling,
misleading, or simply irrelevant. Numerical literacy, the ability to follow
and understand numerical arguments is important for everyone. The ability
to express oneself numerically, to be an author rather than just a reader
is a vital skill in many professions and areas of study. The study of
statistics is therefore essential to a sound education. We must learn how
to read data, critically and with comprehension; we must learn how to
produce data that provide clear answers to important question; and we must
learn sound methods for drawing trustworthy conclusions based on data as
well as acquire ability to effectively communicate valid conclusions.
Statistics teaches you how to gather, organize, and analyze data, and then
to infer the underlying reality from these data. It is a powerful
intellectual method that is applied in many contexts and most disciplines.
Persons in industry and government make decisions that are increasingly
dependent upon the collection and interpretation of data, and employers
demand greater quantitative sophistication from their employees (or
prospective employees). Indeed, in almost every aspect of our daily lives
we confront data and make judgments based on them, about issues ranging
from airline safety to the spread of AIDS. It is now clear that the
Challenger disaster never would have occurred if a statistically wise
person had seen the data. This did not have to be a statistician, but one
(say an engineer) with enough statistical literacy to see the strong
relationship between the temperature and the failure rate of the O-rings.
H.G. Wells anticipated that statistical thinking (numerical literacy) would
one day be as necessary for efficient citizenship as the ability to read
and write. Many individuals and professional groups think that day has
come. One individual has written that:
“It is widely agreed that the critical reading and analysis of texts, the
methodology of experimental science, and the deductive reasoning of
mathematics are broad intellectual methods that should be part of a general
education. It is now claimed by some that reasoning from numerical data —
that is statistics — deserves a similar stature.”
The influential National Science Board has suggested “elementary statistics
and probability should now be considered fundamental for all high school
Statistics students learn to define problems, to think critically, to
analyze and to synthesize which prepares them to explore widely throughout
their professional lives, and to be creative and productive citizens —
regardless of the precise nature of a career. They also learn to discover
the integrity of data, the uncertainty of measurements and, through these,
the development of understanding for the powers and limitations of science.
Moreover, students discover that there are things scientist can do and
other things they cannot do and that experimental results are not exact but
scientists can usually evaluate the range of uncertainty within specified
confidence limits (probabilities). The development of an understanding of
the powers and limitations of science is essential to rational
participation in the resolution of societal issues.
The language of statistics is a foreign language to most students. It is
necessary for students to understand the language in order to understand
the concepts and the statistical procedures. Learning the language of
statistics provides students with insights and an awareness of ideas and
thoughts beyond the realm of previous experience. Statistical language
requires precision and careful attention to exactly communicate valid
conclusions and interpretations, which result from data analysis.