Unit9BasicStatisticalAnalysisofRandomErrors(随机误差的统计学基本分析)Randomerrorsarethosevariablesthatremainaftermistakesaredetectedandeliminatedandallsystematicerrorshavebeenremovedorcorrectedfromthemeasuredvalues.(随机误差是在错误被察觉【detect】和消除【eliminate】后,并且所有系统误差被从测量值中移除或修正后,保留下的那些变量【variable变量、变化n.】)Theyarebeyondthecontroloftheobserver.(它们是观测者无法控制的)Sotherandomerrorsareerrorstheoccurrenceofwhichdoesnotfollowadeterministicpattern.(因此随机误差是不遵循某个确定性【deterministic确定性的】模式【pattern】而发生的误差)Inmathematicalstatistics,theyareconsideredasstochasticvariables,anddespitetheirirregularbehavior,thestudyofrandomerrorsinanywell-conductedmeasuringprocessorexperimenthasindicatedthatrandomerrorsfollowthefollowingempiricalrules:(在数理统计【mathematicalstatistics】中,它们被当成随机变量【stochasticvariable】,尽管它们的行为无规律,在任一正确的【well-conducted原意为品行端正的,这里指测量实验和活动是无误的】测量活动和实验中,对的随机误差的研究显示【indicate】随机误差遵循以下经验法则【empiricalrule】:)⑴Arandomerrorwillnotexceedacertainamount.(随即误差不会超过一个确定的值)⑵Positiveandnegativerandomerrorsmayoccuratthesamefrequency.(正负误差出现的频率相同)⑶Errorsthataresmallinmagnitudearemorelikelytooccurthanthosethatarelargerinmagnitude.(误差数值【magnitude量值、大小】小的比数值大的误差出现可能性大【belikelyto可能】)⑷Themeanofrandomerrorstendstozeroasthesamplesizetendstoinfinite.(当【as】样本大小【samplesize】趋近于无穷【infinite】时,随机误差的平均值趋近于0)Inmathematicalstatistics,randomerrorsfollowstatisticalbehaviorallawssuchasthelawsofprobability.(在数理统计中,随机误差遵循统计学的【statistical】行为【behavioral行为的】规律,如概率法则)Acharacteristictheoreticalpatternoferrordistributionoccursuponanalysisofalargenumberofrepeatedmeasurementsofaquantity,whichconformtonormalorGaussiandistribution.(发生在一个量的大量重复观测分析【analysisn.】中的误差分布的一个特征理论模式,遵照【conformto遵照】正态或高斯分布)【在对一个量进行大量重复观测分析后,得到一个误差分布的理论特征——正态或高斯分布】Theplotoferrorsizesversusprobabilitieswouldapproachasmoothcurveofthecharacteristicbell-shape.(误差大小与【versus与、与……的关系、与……相对】概率的关系图,接近一条光滑的特有的【characteristic特有的】钟形曲线。)Thiscurveisknownasthenormalerrordistributioncurve.(这条曲线被称为正态分布曲线)Itisalsocalledtheprobabilitydensityfunctionofanormalrandomvariable.(也叫做正态随机变量【normalrandomvariable】的概率密度【probabilitydensity】函数)Itisimportanttonoticethatthetotalareaoftheverticalbarsforeachplotequals1.(需特别注意的是,每个图的条形图总面积为1。)Thisistruenomatterthevalueofn(thenumberofsinglecombinedmeasurements),andthustheareaunderthesmoothnormalerrordistributioncurveisequalto1.(无论【nomatter】n(单一的联合的测量数目【独立观测数】)是多少,在光滑的误差正态分布曲线下的面积都是1。)Ifaneventhasaprobabilityof1,itiscertaintooccur,andthereforetheareaunderthecurverepresentsthesumofalltheprobabilitiesoftheoccurrenceoferrors.(如果一件事的概率为1,它一定会发生,因此曲线下方的面积代表了所有误差发生的概率。)Anumberofpropertiesthatrelatearandomvariableanditsprobabilitydensityfunctionareusefulinourunderstandingofitsbehavior.(有许多工具【property】与随机变量和它的概率密度函数有关,有助于我们理解...