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		<id>https://en.formulasearchengine.com/w/index.php?title=Log-polar_coordinates&amp;diff=266935</id>
		<title>Log-polar coordinates</title>
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		<updated>2014-09-12T17:52:17Z</updated>

		<summary type="html">&lt;p&gt;172.251.103.105: /* Discrete geometry */&lt;/p&gt;
&lt;hr /&gt;
&lt;div&gt;If you have not realized methods to sharpen a knife and maintain its edge, these are among the first things it&#039;s best to study. You will be extra independent and as environment [http://Wiki.Paconun.eu/index.php/Where_To_Buy_A_Machete friendly] as doable. Whittling is an ancient craft. It is wonderfully contemplative and could even be spiritually meditative. It&#039;s the journey that issues more than the top result. When you have no care to hurry, if you want to take your time and see what happens, what&#039;re you waiting for? As with something on the Internet, returning hunting knives may be very troublesome, so make when you plan on shopping for these the local retailer, this will not be a problem.&amp;lt;br&amp;gt;&amp;lt;br&amp;gt;&amp;lt;br&amp;gt;&amp;lt;br&amp;gt;The a hundred and ten was born in 1963, after two years of tinkering by C.J. Buck (who now runs the corporate), his father, Al, and an 85-year-outdated toolmaker named Man Hoosier. It took two years as a result of the a hundred and ten had to be good. The objective was to make a folding knife that performed as well as a fixed-blade knife, something that hadn’t but been completed. Oh, and on top of that, the knife needed to be so [http://en.wikipilipinas.org/index.php?title=Best_Type_Of_Machete widespread] it might save Buck from monetary damage and pull it out of the deeply purple hole it was in.&amp;lt;br&amp;gt;&amp;lt;br&amp;gt;Whittling has been around for a lot of hundreds of years. All the best way again to the days of cavemen. One could say that it&#039;s because we began to whittle that [http://galab-work.cs.pusan.ac.kr/Sol09B/?document_srl=483359&amp;amp;mid=FreeBoard&amp;amp;listStyle=&amp;amp;cpage= expertise started]. It was the shaping of wooden, after all-after the discovery of sharp edges-that sparked human creativeness to make carts, cooking implements and clothes, weapons for looking and methods of meals gathering. Who would&#039;ve thought? So you wish to whittle wood. Good for you. Whittling is the simple elimination of pare shavings or reducing small bits from a chunk of wood with a knife No more, no less. So what does it take to develop into a very good whittler?&amp;lt;br&amp;gt;&amp;lt;br&amp;gt;Survival knives are so important in a survival state of affairs, that when you had been solely capable of convey one merchandise with you, you would be silly not to pick a superb quality survival knife. While survival knives are available many sizes and shapes, this record of the highest 5 survival knives on this planet will slender that checklist down for you fairly a bit. Each one discussed above you could possibly belief with your life and consider me many have. Survival knives can also be used for family tenting and lots of different uses around the house making them invaluable instruments for on a regular basis use.&amp;lt;br&amp;gt;&amp;lt;br&amp;gt;Spyderco paid a substantial amount of attention to the refinement of the ergonomics on the Tenacious. The knife fills my hand completely with out being cumbersome. The thickness is spot on and makes the [http://Sss.chaoslab.ru/tracker/mim_plugs/newticket?reporter=anonymous&amp;amp;summary=AttributeError%3A+%27Environment%27+object+has+no+attribute+%27get_db_cnx%27&amp;amp;description=I+t%27s+pretty+crucial+to+pick+the+most+effective+survival+machete+out+there+in+the+marketplace+today.+A+multi-purpose+finest+machete+on+the+marketplace+is+crucial+to+carry+with+your+self+in+a+outside+or+survival+adventure.+A+fantastic+machete+can+enhance+the+efficiency+of+the+function+rate+in+critical+tasks+such+as+Chopping+Wood+%2C+Constructing+Shelters+and+Clearing+Brush%0D%0A%0D%0A%0D%0A%0D%0AThey+are+Individuals%2C+Too%21+Full+a+Marked+Destination+on+the+Map+without+Killing+a+Walker+Xbox+360+-+30+Gamer+Points+Intense+Conditioning+Sprint+Until+You%27re+Exhausted+10+Instances+in+A+single+Level+Xbox+360+-+10+Gamer+Points+Bare+minimum%3F+For+me+it+would+be+a+good+knife.+With+a+knife+I+can+make+shelter%2C+fire+and+other+tools.+But+a+water+bottle+would+also+be+valuable%2C+but+not+certainly+important+where+I+generally+am+in+the+woods.+For+the+absolute+bare+minimum+all+you+will+need+is+your+brain+loaded+with+knowledge.+But+as+for+minimum+%27stuff%27+a+very+good+edged+tool+is+it.+A+knife+or+tomahawk%2Fhatchet+or+a+short+ax+all+would+work.+With+an+edged+tool+you+can+make+other+tools+to+survive.+his+knife+doesn%27t+normally+get+reproduced+incredibly+accurate+to+the+original+not+that+i+am+confident+it+wants+to+be%0D%0A%0D%0AYes.+Guns.+Large-scary-guns.+Guns+and+survival+go+hand+in+hand%2C+especially+in+the+course+of+an+economic+or+social+collapse.++Should+you+have+virtually+any+queries+concerning+in+which+along+with+tips+on+how+to+use+%5Bhttp%3A%2F%2Fwww.thebestpocketknifereviews.com%2Fbest-survival-machete-on-the-market-today%2F+buy+Machete%5D%2C+you+can+contact+us+on+our+webpage.+To+bring+up+guns+in+a+prepping+article+almost+usually+draws+criticism+of+militancy+and+extremism+from+suburban+basted+over-privileged+adolescent+hippies+who+have+read+%E2%80%9CInto+The+Wild%E2%80%9D+way+too+many+instances+and+think+survival+is+about+%E2%80%9Ccommuning+with+nature%E2%80%9D.+Sorry+kids%2C+but+as+a+great+deal+as+I+enjoy+nature%2C+as+quickly+as+you+turn+your+back+on+it%2C+you+finish+up+a+pre-digested+meal+spread+like+almond+butter+across+30+acres+of+grizzly+valley.+On+the+other+side+of+the+coin%2C+firearms+analysis+usually+draws+endless+opinions+and+puffy+chested+%E2%80%9Cexpertise%E2%80%9D+from+armchair+generals+and+%E2%80%9Cinvincible+specific-ops+superheroes%E2%80%9D.%0D%0A%0D%0AIt+really+is+essential+to+get+a+knife+with+sturdy+attributes+and+diverse+functions%2C+so+that+it+can+act+as+an+all+objective+tool+to+support+you+construct+whatever+is+required+for+your+survival.+Becoming+nicely+prepared+with+the+ideal+survival+knife+could+make+all+the+distinction+to+your+security.+Machetes+range+in+cost+from+%2415+to+properly+more+than+%24one+hundred%2C+to+a+specific+extent+the+price+does+reflect+the+top+quality+and+workmanship+of+the+product.+You+really+should+still+be+capable+to+uncover+a+versatile%2C+sturdy%2C+properly+crafted%2C+quality+machete+for+about+%2425-50.+The+machete+is+pretty+possibly+the+most+beneficial%2C+efficient+survival+tool+that+one+particular+can+own+and+should+really+not+be+missing+from+any+true+outdoorsman%27s+survival+gear.+Aluminumwith+Survival+Kit+Ultimate+Survival+Knife+%21+%28Value+-+%2427%29+Greatest+10+Machetes%0D%0A%0D%0AI+have+normally+been+interested+in+wearing+one+of+the+Suunto+M9+Wrist+compasses%2C+as+they+are+handy+as+a+backup+compass%2C+and+can+be+aimed+through+the+side.+Nevertheless%2C+I+usually+wear+a+watch+on+my+left+wrist+and+a+survival+bracelet+on+my+ideal+wrist.+I+really+did+not+want+to+give+up+either.+We+love+the+outdoors%2C+and+we+give+some+of+the+greatest+products+for+camping.+We+give+the+ideal+Brunton+compasses+and+stoves%2C+ProForce+backpacks+and+sleeping+bags%2C+dozens+of+firestarters+and+saws+and%2C+of+course%2C+the+world%27s+greatest+choice+of+camping+and+survival+knives.+Go+for+solid+metal%2C+that+signifies+you+need+to+opt+for+a+solid%2C+heavy+and+trustworthy+machete%2C+remain+away+from+flimsy+blades%2C+they+are+of+low+high-quality.+The+absolute+most+effective+targets+to+strike+in+combat+%28they%27re+not%0D%0A%0D%0ALastly+never+forget+to+verify+reviews%21+Even+though+the+machete+you+want+to+buy+may+perhaps+appear+fantastic+other+folks+who+have+reviewed+it+may+possibly+be+able+to+bring+complications+or+defects+to+your+attention.+Blade+thickness+is+also+a+factor+in+how+nicely+the+machete+will+perform.+On+the+other+hand%2C+as+long+as+the+blade+is+created+from+high+quality+steel%2C+thickness+becomes+far+more+of+a+preference.+Thicker+blades+%281%2F4%E2%80%9D%29+commonly+mean+heavier+machetes+superior+suited+for+chopping+limbs+or+cutting+kindling+and+firewood.+Thinner+blades+%28no+significantly+less+than+1%2F8%E2%80%9D%29+are+lighter+and+execute+greater+in+brush%2C+vines%2C+and+other+shrubbery.+It+cost+drastically+additional+than+the+uber-flexible+low-cost+machete+hanging+subsequent+to+it%2C+but+paying+for+a+good+quality+item+shouldn%27t+scare+you.+Single+snap+retrieval+on+the+Cold+Steel+Kukri%0D%0A%0D%0Avery+best+machete+for+survival+very+best+survival+machete+survival+machete+Survival+Knife+All+The+Ideal+To+Pick+The+Very+best+Survival+Machete+greatest+machete+Machete+The+Machete+Picking+a+%5Bhttp%3A%2F%2Fphotobucket.com%2Fimages%2FSurvival+Survival%5D+Machete+Ideal+Survival+Machete+Models+Prime+modest+survival+machetes+Survival+Style+Bolo+Machete+Latin+Style+Survival+Machete+Click+Right+here+for+the+Top+Machetes+on+Amazon+How+to+Choose+the+Greatest+Survival+Machete+Gator+Machete+Machete+Blade+Gerber+Gator+Machete+Junior+and+Ka-Bar+Black+Kukri+Machete+Greatest+Obtain+Ontario+Knife+8335+Machete+Black+for+Unique+Now+%E2%80%93+Survival+Knife+Gator+Machete+Pro+The+Machete+Blade+The+Pocket+Survival+Guide+Survival+Gear+Wholesale+Survival+Machete+What+is+the+finest+survival+machete%3F+This+is+the+ultimate+guide+to+selecting+the+very+best+survival+machete.+For+a+list+of+the+ideal+machetes%2C+take+a+look+at+-survival-machete%2F+Survival+Books+Gerber%0D%0A%0D%0AWorrying+a+lot+about+the+probabilities+of+illness+they+set+about+obtaining+natural+remedies.+When+they+killed+animals%2C+they+would+reduce+open+its+stomach+collected+the+gastric+juice+and+dried+this+in+the+sun.+They+ground+the+solidified+mass+into+a+greenish-white+powder+%26+kept+it+in+a+bottle%2C+it+proved+an+exceptional+gastric+tonic.+Magnifying+lens+for+beginning+fire+%28The+magnesium+or+steel+wool+is+a+backup+to+the+lens+-+the+lens+does+not+work+when+it+really+is+overcast+or+dark+and+it+is+not+valuable+if+all+the+things+is+soaking+wet%2C+but+you+can+run+out+of+magnesium+powder+and+the+bars+are+murder+on+a+knife.+The+lens+in+no+way+runs+out.%29+In+the+west%2C+we+train%2C+we+educate+our+young+guys+to+the+very+best+of+our+potential.+And+in+the+finish+the+practical+experience+of+combat+is+their+finishing+college.&amp;amp;create=Create knife feel] solid. I have average sized palms with barely brief fingers. Additionally, the curvature on the belly of the blade permits you to use the complete [http://www.Thebestpocketknifereviews.com/best-survival-machete-on-the-market-today/ Best Machete On The Market] length while sustaining maximum chopping power since it doesn’t taper off too rapidly. Value As a result of the blade is closed or coated when not in use, folder knives important reduce the opportunity of accidental cuts. The blade edge is also protected from dulling and dings. Variety&amp;lt;br&amp;gt;&amp;lt;br&amp;gt;With a closed size of 3.eight inches and complete weight of solely 2.6 ounces, the Gerber Reply SM knife model 31-000578 is a small sturdy knife that&#039;s nice for daily use. It has a superb edge drop level blade that is quickly accessible with Gerber F.A.S.T assisted opening system. The black anodized aluminum handle has textured inlays for a firm grip irregardless of situations. With its traditional look and the polished brass [http://bitcoinaddict.com/webid/item.php?id=97010&amp;amp;mode=1 bolstered] handle, it is a knife for the ages and continues to be popular years after its launch.&amp;lt;br&amp;gt;&amp;lt;br&amp;gt;Within the United Kingdom it&#039;s unlawful to hold a knife having a blade greater than 3 inches (seventy six mm) in length in public without &amp;quot;good motive&amp;quot;. The phrases &amp;quot;in public&amp;quot; and &amp;quot;good reason&amp;quot; are usually not defined, however examples of &amp;quot;religious duty&amp;quot;, &amp;quot;nationwide [http://www.foxnews.com/us/2013/09/18/student-suspended-for-10-days-for-accidentally-bringing-pocket-knife-to/ cold steel knife] gown&amp;quot; and &amp;quot;requirement of employment or pastime&amp;quot; are given. It is left as much as a police officer&#039;s individual subjective discretion, and in the end a magistrate to resolve if a knife is being carried &amp;quot;in public&amp;quot;, and for a &amp;quot;good purpose&amp;quot;. The onus lies on the officer to show that intent.&lt;/div&gt;</summary>
		<author><name>172.251.103.105</name></author>
	</entry>
	<entry>
		<id>https://en.formulasearchengine.com/w/index.php?title=Isaac_Roberts&amp;diff=8461</id>
		<title>Isaac Roberts</title>
		<link rel="alternate" type="text/html" href="https://en.formulasearchengine.com/w/index.php?title=Isaac_Roberts&amp;diff=8461"/>
		<updated>2014-01-29T23:49:59Z</updated>

		<summary type="html">&lt;p&gt;172.251.194.102: /* Interest in astronomy */&lt;/p&gt;
&lt;hr /&gt;
&lt;div&gt;In [[population genetics]], &#039;&#039;&#039;Ewens&#039; sampling formula&#039;&#039;&#039;, describes the probabilities associated with counts of how many different [[allele]]s are observed a given number of times in the sample.&lt;br /&gt;
&lt;br /&gt;
==Definition==&lt;br /&gt;
Ewens&#039; sampling formula, introduced by [[Warren Ewens]], states that under certain conditions (specified below), if a random sample of &#039;&#039;n&#039;&#039; [[gamete]]s is taken from a population and classified according to the [[gene]] at a particular [[locus (genetics)|locus]] then the [[probability]] that there are &#039;&#039;a&#039;&#039;&amp;lt;sub&amp;gt;1&amp;lt;/sub&amp;gt; [[allele]]s represented once in the sample, and &#039;&#039;a&#039;&#039;&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; alleles represented twice, and so on, is&lt;br /&gt;
&lt;br /&gt;
:&amp;lt;math&amp;gt;\operatorname{Pr}(a_1,\dots,a_n; \theta)={n! \over \theta(\theta+1)\cdots(\theta+n-1)}\prod_{j=1}^n{\theta^{a_j} \over j^{a_j} a_j!},&amp;lt;/math&amp;gt;&lt;br /&gt;
&lt;br /&gt;
for some positive number &#039;&#039;θ&#039;&#039;, whenever &#039;&#039;a&#039;&#039;&amp;lt;sub&amp;gt;1&amp;lt;/sub&amp;gt;, ..., &#039;&#039;a&#039;&#039;&amp;lt;sub&amp;gt;&#039;&#039;n&#039;&#039;&amp;lt;/sub&amp;gt; is a sequence of nonnegative integers such that&lt;br /&gt;
&lt;br /&gt;
:&amp;lt;math&amp;gt;a_1+2a_2+3a_3+\cdots+na_n=n.\,&amp;lt;/math&amp;gt;&lt;br /&gt;
&lt;br /&gt;
The phrase &amp;quot;under certain conditions&amp;quot;, used above, must of course be made precise.  The assumptions are:&lt;br /&gt;
* The sample size &#039;&#039;n&#039;&#039; is small by comparison to the size of the whole population; and&lt;br /&gt;
* The population is in statistical equilibrium under [[mutation]] and [[genetic drift]] and the role of selection at the locus in question is negligible; and&lt;br /&gt;
* Every mutant allele is novel.  (See also [[idealised population]].)&lt;br /&gt;
&lt;br /&gt;
This is a [[probability distribution]] on the set of all [[integer partition|partitions of the integer]] &#039;&#039;n&#039;&#039;.  Among probabilists and statisticians it is often called the &#039;&#039;&#039;multivariate Ewens distribution&#039;&#039;&#039;.&lt;br /&gt;
&lt;br /&gt;
== Mathematical properties ==&lt;br /&gt;
&lt;br /&gt;
When &#039;&#039;θ&#039;&#039;&amp;amp;nbsp;=&amp;amp;nbsp;0, the probability is 1 that all &#039;&#039;n&#039;&#039; genes are the same.  When &#039;&#039;θ&#039;&#039;&amp;amp;nbsp;=&amp;amp;nbsp;1, then the distribution is precisely that of the integer partition induced by a uniformly distributed [[random permutation]].  As &#039;&#039;θ&#039;&#039;&amp;amp;nbsp;→&amp;amp;nbsp;∞, the probability that no two of the &#039;&#039;n&#039;&#039; genes are the same approaches&amp;amp;nbsp;1.&lt;br /&gt;
&lt;br /&gt;
This family of probability distributions enjoys the property that if after the sample of &#039;&#039;n&#039;&#039; is taken, &#039;&#039;m&#039;&#039; of the &#039;&#039;n&#039;&#039; gametes are chosen without replacement, then the resulting probability distribution on the set of all partitions of the smaller integer &#039;&#039;m&#039;&#039; is just what the formula above would give if &#039;&#039;m&#039;&#039; were put in place of&amp;amp;nbsp;&#039;&#039;n&#039;&#039;.&lt;br /&gt;
&lt;br /&gt;
The Ewens distribution arises naturally from the [[Chinese restaurant process]].&lt;br /&gt;
&lt;br /&gt;
==See also==&lt;br /&gt;
* [[Coalescent theory]]&lt;br /&gt;
* [[Unified neutral theory of biodiversity]]&lt;br /&gt;
&lt;br /&gt;
{{inline|date=August 2011}}&lt;br /&gt;
==Notes==&lt;br /&gt;
* Warren Ewens, &amp;quot;The sampling theory of selectively neutral alleles&amp;quot;, &#039;&#039;Theoretical Population Biology&#039;&#039;, volume 3, pages 87&amp;amp;ndash;112, 1972.&lt;br /&gt;
* J.F.C. Kingman, &amp;quot;Random partitions in population genetics&amp;quot;, &#039;&#039;Proceedings of the Royal Society of London, Series B, Mathematical and Physical Sciences&#039;&#039;, volume 361, number 1704, 1978.&lt;br /&gt;
* S. Tavare and W. J. Ewens, [http://www.cmb.usc.edu/people/stavare/STpapers-pdf/TE97.pdf &amp;quot;The Multivariate Ewens distribution&amp;quot;]. (1997, Chapter 41 from the reference below).&lt;br /&gt;
* N.L. Johnson, S. Kotz, and N. Balakrishnan (1997) &#039;&#039;Discrete Multivariate Distributions&#039;&#039;, Wiley. ISBN 0-471-12844-9.&lt;br /&gt;
&lt;br /&gt;
{{ProbDistributions|multivariate}}&lt;br /&gt;
&lt;br /&gt;
{{DEFAULTSORT:Ewens&#039;s Sampling Formula}}&lt;br /&gt;
[[Category:Probability distributions]]&lt;br /&gt;
[[Category:Population genetics]]&lt;br /&gt;
[[Category:Discrete distributions]]&lt;/div&gt;</summary>
		<author><name>172.251.194.102</name></author>
	</entry>
	<entry>
		<id>https://en.formulasearchengine.com/w/index.php?title=Calculator_input_methods&amp;diff=9696</id>
		<title>Calculator input methods</title>
		<link rel="alternate" type="text/html" href="https://en.formulasearchengine.com/w/index.php?title=Calculator_input_methods&amp;diff=9696"/>
		<updated>2013-12-20T08:10:18Z</updated>

		<summary type="html">&lt;p&gt;172.251.178.32: /* Reverse Polish notation (RPN) (postfix notation) */&lt;/p&gt;
&lt;hr /&gt;
&lt;div&gt;{{Probability fundamentals}}&lt;br /&gt;
&lt;br /&gt;
In [[probability theory]], the &#039;&#039;&#039;complement&#039;&#039;&#039; of any [[event (probability theory)|event]] &#039;&#039;A&#039;&#039; is the event [not&amp;amp;nbsp;&#039;&#039;A&#039;&#039;], i.e. the event that &#039;&#039;A&#039;&#039; does not occur.&amp;lt;ref&amp;gt;Robert R. Johnson, Patricia J. Kuby: &#039;&#039;Elementary Statistics&#039;&#039;. Cengage Learning 2007, ISBN 978-0-495-38386-4, p. 229 ({{Google books|DWCAh7jWO98C|restricted online copy|page=229}})&amp;lt;/ref&amp;gt;  The event &#039;&#039;A&#039;&#039; and its complement [not&amp;amp;nbsp;&#039;&#039;A&#039;&#039;] are [[mutually exclusive]] and [[Collectively exhaustive events|exhaustive]]. Generally, there is only one event &#039;&#039;B&#039;&#039; such that &#039;&#039;A&#039;&#039; and &#039;&#039;B&#039;&#039; are both mutually exclusive and exhaustive; that event is the complement of &#039;&#039;A&#039;&#039;.  The complement of an event &#039;&#039;A&#039;&#039; is usually denoted as &#039;&#039;A&amp;amp;prime;&#039;&#039;, &#039;&#039;A&amp;lt;sup&amp;gt;c&amp;lt;/sup&amp;gt;&#039;&#039; or &#039;&#039;{{overline|A}}&#039;&#039;.&lt;br /&gt;
&lt;br /&gt;
For example, if a typical coin is tossed and one assumes that it cannot land on its edge, then it can either land showing &amp;quot;heads&amp;quot; or &amp;quot;tails.&amp;quot; Because these two [[Outcome (probability)|outcomes]] are mutually exclusive (i.e. the coin cannot simultaneously show both heads and tails) and collectively exhaustive (i.e. there are no other possible outcomes not represented between these two), they are therefore each other&#039;s complements. This means that [heads] is logically equivalent to [not tails], and [tails] is equivalent to [not heads].&lt;br /&gt;
&lt;br /&gt;
==Complement rule==&lt;br /&gt;
In a [[Experiment (probability theory)|random experiment]], the probabilities of all possible events (the [[sample space]]) must total to 1&amp;amp;mdash; that is, some outcome must occur on every trial. For two events to be complements, they must be [[Collectively exhaustive events|collectively exhaustive]], together filling the entire sample space. Therefore, the probability of an event&#039;s complement must be [[Unity (mathematics)|unity]] minus the   &lt;br /&gt;
 probability of the event.&amp;lt;ref name=&amp;quot;yates&amp;quot;&amp;gt;{{cite book | last = Yates | first = Daniel S. | last2 = Moore | first2 = David S | last3 = Starnes | first3 = Daren S. | year = 2003 | title = The Practice of Statistics | edition = 2nd | publisher = [[W. H. Freeman and Company|Freeman]] | location = New York | url = http://bcs.whfreeman.com/yates2e/ | isbn = 978-0-7167-4773-4}}&amp;lt;/ref&amp;gt;{{rp|342-343}} That is, for an event &#039;&#039;A&#039;&#039;,&lt;br /&gt;
:&amp;lt;math&amp;gt;P(A^c) = 1 - P(A).&amp;lt;/math&amp;gt;&lt;br /&gt;
Equivalently, the probabilities of an event and its complement must always total to 1. This does not, however, mean that &#039;&#039;any&#039;&#039; two events whose probabilities total to 1 are each other&#039;s complements; complementary events must also fulfill the condition of [[Mutually exclusive events|mutual exclusivity]].&lt;br /&gt;
&lt;br /&gt;
===Example of the utility of this concept===&lt;br /&gt;
Suppose one throws an ordinary six-sided die eight times.  What is the probability that one sees a &amp;quot;1&amp;quot; at least once?&lt;br /&gt;
&lt;br /&gt;
It may be tempting to say that&lt;br /&gt;
&lt;br /&gt;
:  Pr([&amp;quot;1&amp;quot; on 1st trial] or [&amp;quot;1&amp;quot; on second trial] or ... or [&amp;quot;1&amp;quot; on 8th trial])&lt;br /&gt;
&lt;br /&gt;
:= Pr(&amp;quot;1&amp;quot; on 1st trial) + Pr(&amp;quot;1&amp;quot; on second trial) + ... + P(&amp;quot;1&amp;quot; on 8th trial)&lt;br /&gt;
&lt;br /&gt;
:= 1/6 + 1/6 + ... + 1/6.&lt;br /&gt;
&lt;br /&gt;
:= 8/6 = 1.3333... (...and this is clearly wrong.)&lt;br /&gt;
&lt;br /&gt;
That cannot be right because a probability cannot be more than 1.  The technique is wrong because the eight events whose probabilities got added are not mutually exclusive.&lt;br /&gt;
&lt;br /&gt;
Instead one may find the probability of the complementary event and subtract it from 1, thus:&lt;br /&gt;
&lt;br /&gt;
:   Pr(at least one &amp;quot;1&amp;quot;) = 1 &amp;amp;minus; Pr(no &amp;quot;1&amp;quot;s)&lt;br /&gt;
&lt;br /&gt;
:= 1 &amp;amp;minus; Pr([no &amp;quot;1&amp;quot; on 1st trial] and [no &amp;quot;1&amp;quot; on 2nd trial] and ... and [no &amp;quot;1&amp;quot; on 8th trial])&lt;br /&gt;
&lt;br /&gt;
:= 1 &amp;amp;minus; Pr(no &amp;quot;1&amp;quot; on 1st trial) &amp;amp;times; Pr(no &amp;quot;1&amp;quot; on 2nd trial) &amp;amp;times; ... &amp;amp;times; Pr(no &amp;quot;1&amp;quot; on 8th trial)&lt;br /&gt;
&lt;br /&gt;
:= 1 &amp;amp;minus;(5/6) &amp;amp;times; (5/6) &amp;amp;times; ... &amp;amp;times; (5/6)&lt;br /&gt;
&lt;br /&gt;
:= 1 &amp;amp;minus; (5/6)&amp;lt;sup&amp;gt;8&amp;lt;/sup&amp;gt;&lt;br /&gt;
&lt;br /&gt;
:= 0.7674...&lt;br /&gt;
&lt;br /&gt;
==See also==&lt;br /&gt;
*[[Negation|Logical complement]]&lt;br /&gt;
*[[Exclusive disjunction]]&lt;br /&gt;
*[[Binomial probability]]&lt;br /&gt;
&lt;br /&gt;
==References==&lt;br /&gt;
{{reflist}}&lt;br /&gt;
&lt;br /&gt;
==External links==&lt;br /&gt;
*[http://highered.mcgraw-hill.com/sites/dl/free/0072549076/79746/ch04_p175.pdf &#039;&#039;Complementary events&#039;&#039;] - (free) page from probability book of [[McGraw-Hill]]&lt;br /&gt;
&lt;br /&gt;
{{DEFAULTSORT:Complementary Event}}&lt;br /&gt;
[[Category:Probability theory]]&lt;/div&gt;</summary>
		<author><name>172.251.178.32</name></author>
	</entry>
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