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8/9/2019 Stats 10 Ee Sample
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Data Analysis Project
8/9/2019 Stats 10 Ee Sample
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Misleading Statistics
Companies and media often manipulate and skew certain statistics
to their advantages in order to deliver their messages more
convincingly.
Because there are many ways of presentation of statistics, it is quite
easy to manipulate the information in a misleading way. If the statistics include surveying, a proper way of selection of
population is important (Simple Random Sampling, Clustered
Sampling, Stratified Random Sampling, and etc..
!e all must "e aware of these misleading graphs and in what forms
they are presented to us, and "e a"le to analy#e, and fi$ suchgraphs so that they are no longer misleading, to the "enefit of our
society.
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Two different bar graphs are made from
the same survey of favorite foods:
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The same information can be accurately
presented in a non-misleading way :
If we take the same
information and present
it in a pie graph, we can
see the more accurate
result of the survey.
%nlike the previousgraph which depicted
hot dogs as the favorite
food "y misrepresenting
the origin on the y&a$is,
this pie graph shows
that all three foods areequally preferred, a
more realistic result.
Favorite Foods
Pizza33%
Hot Dogs
34%
Hamburgers
33%
Pizza
Hot Dogs
Hamburgers
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omparative auses of Annual Deaths in
the !nited States " Provided by D
Certain crucial
information are
missing. 'here is no
way for us to know
whether or not CC
has counted smokers
who have died fromdiseases or accidents.
'here is a good
chance that any
smoker that died from
a disease has "een
counted as those that
died from smoking.
)ere is a question to
ask the CC*
+ simple glance at this graph willmake us conclude that smoking
is the leading cause of death
among +mericans. )owever, an
in&depth analysis of this graph
will easily tell us that it is greatly
misleading.
+ person who smokes has died from a heart disease. !hat was
his cause of death
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#ays to fi$ misleading graphs - %
-ne way to fi$ a
misleading graph is to
present in a different
way, like what we
have done for the
previous
information(favorite
foods. )owever, it
seems there is no
significant change in
the information even
after we have made a
pie graph from theinitial "ar graph. !e
now have to question
the method of
construction of the
graph "y the CC.
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#ays to fi$ misleading graphs - %%
& )ow the CC has collected their data is very dou"tful. 'hegraph does not provide any information a"out the num"erof deaths caused "y smoking. If smoking is not the primarycause of death, then it should not "e the cause of death.
& 'he CC may say that /0,111 people who have diedwere smokers, "ut they cannot say that they have diedbecause ofsmoking.
& 'he graph presented on the ne$t slide is a more accurategraph regarding the causes of annual deaths in the %nitedStates*
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&evised 'raph " Percentage of
Smo(ers in )ach ause of Annual
Death in the !nited States
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Analysis of the &evised 'raph
2rom the revised graph, we can tell that
certain percentages of people who havedied from each disease smoked. 'his
graph does not imply that smoking is the
leading cause of death in the %nited
States. It does, however, imply that
smoking contri"utes to deaths in the
%nited States.
2or instance, we can assume that smoking is closely related with cardio
vascular diseases such as heart disease and cancer, for chemical included in a
cigarette such as tar is a"le to "lock "lood vessels, ultimately causing heart
diseases. !e can also assume that smoking is intimately related to deaths
cause "y usage of drugs.
!e cannot draw a 3fact4 from most statistics. It is important to conduct the
survey and the construction of presentation as in the most realistically accurate,
relia"le, and non&misleading way as possi"le, and the conclusions drawn from
the presentation, must not "e general, "ut acutely specific.
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Price Per *arrel of +ight rude ,il
+eaving Saudi Arabia on an. /
'he pictograph on the left indicates the
amount of increase in crude oils in
transport from Saudi +ra"ia. 'he ratio of
the si#e of the "arrel to the actual price is
not in proportion. 'he difference in si#es
of the "arrels are conveyed toe$aggerate the increase or decrease in
the price of a "arrel of crude oil. It is,
moreover, hard for readers to visually
compare prices in each year. 'herefore,
this pictograph is potentially misleading.
Year Price Increase
1973 $2.41
1974 $10.95 354.36%
1974 $10.46 -4.47%
1976 $11.51 10.04%
1977 $12.09 5.04%
1978 $12.70 5.05%
1979 $13.34 5.04%
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&evised 'raph
Instead of using
"arrels with
different si#es to
descri"e the
increase in prices,
a properly
constructed "ar
graph would
present the
information moreaccurately.
Price Per *arrel of +ight rude ,il +eaving Saudi Arabia on-an. /
51.1156.11
5.11
57.11
50.11
5/1.115/6.11
5/.11
5/7.11
/89: /89 /89; /897 /899 /890 /898
0ears
PricePer*arrel
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&evised 'raph - %%
Price Per *arrel of +ight rude ,il +eaving SaudiArabia on -an. /
51.11
56.11
5.11
57.11
50.11
5/1.11
5/6.11
5/.11
5/7.11
/89: /89 /89; /897 /899 /890 /898
0ears
PricesPer*arrel
- Another ade1uate way of fi$ing the graph2 showing the gradual
increase in the oil prices effectively through a line graph.
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hevy Advertisement
'his is a misleading graph to serve a purpose
which is to indicate that Chevy is the most
preferred car among people, thus possi"ly
persuading many others to purchase Chevy.
)owever, if we look at the graph closely, it can
"e seen that the y&a$is does not start at #ero.
'he viewer of this graph may take thismisleading graph for how it looks, and will
procure a false and inaccurate information.
In order to fi$ this misleading graph, we would
have to possess a precise and accurate
information with which we could organi#e a
properly designed graph. 'he y&a$is of the
graph must also "egin from 1, in order to
display an accurate comparison. !ithout
sufficient information, we cannot "ut simply
"e aware that graphs such as this are
misleading "ecause of their o"scurity of the
origin on the y&a$is.
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#hat ma(es some statistical
information accurate and reliable3
Statistics is a set of methods that are used to collect and analy#e data.
Because it is used to help many people to make good decisions a"out
uncertain situations, many people tend to "elieve any statistic that is
presented to them "y a company. )owever, as you have seen through our
presentation, statistics are very easy to manipulate< without an adequate
understanding and analysis of the statistical information, it is easy for us to
take misleading statistics seriously. +ccurate and relia"le statistics come from
proper procedure of defining the problem2 collecting the data2 analy4ing
the data2 andreporting the data.
'hese procedures must "e done rationally and as accurately as possi"le, inorder to prevent the statistics from "ecoming misleading.
!e will e$plain the adequate ways to conduct the procedures, and
ultimately to make accurate and relia"le statistics.
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Defining the Problem
=very word in a statistical pro"lem must "e definede$tremely specifically and accurately. 2or e$ample,if the pro"lem was 3counting the num"er of
inha"itants of >errisdale, ?ancouver, on a specificdate, we would have to define inhabitantsto knowwho to count into the survey. +lso, >errisdale must"e defined specifically in order to decide where tostop the survey. 2actors such as new"orn "a"ies in
the hospital must "e taken into consideration. If oneof these pieces of information is not clearly define, itwould "e e$tremely difficult to "egin gathering data.
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ollecting the Data
2or each kind of pro"lem, different information isneeded, and so is the method of collecting the data.-ne of the most important parts of esta"lishing astatistic is to design an effective way of collecting data.!e collect data from a population or from a sample.!hen the population of the survey is selected from asample, the selected population must "e a"le toprovide e$actly required information for the purpose of
the survey. 'he most e$acting and informative form ofdata collection for comparisons is randomizedcontrolled experiment. 'he population is divided intorandomly separated groups, and are selcted randomly.
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Analy4ing the Data
5 )$ploratory Methods 5
'his method often involves a lot of calculating averages and percentages, and displaying
the information on a graph. +lthough =$ploratory methods may provide many pieces
of information, it may not answer specific questions or make definite statements
a"out a pro"lem.
5 onfirmatory Methods 5
'his method is used to conclude the results of the survey and the statistical information
"y answering specific questions. 2or e$ample, using a confirmatory method, a
statistician can say 3-il @rices leaving Saudi +ra"ia has "een increasing, and will
increase in prices.4
Aot one of these methods should "e overlooked. Both methods should "e used
e$tensively to analy#e the results of a statistical activity and will have to come to
varieties of e$tremely specific conclusions with credi"ility and accuracy.
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&eporting the &esults
Inference is used to draw conclusion from a statistical activity