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rorunactta Pambhary 2020 +0190 -0004 Pertemuan og “Provanitity ang samples the '- Sompis, Popuiatiansy and! Dktiibutin of Sample Means” * The location of a score ina Sample OF In a population Can be represented with a 2-score * Researcher Lypicaty wont to study entice camples rather than Single scores “Sample provides estimate op the population “Test Involve transforming somple meah 10 0 B-sore . Sampling error is the natural AIS CrepaNty, or amount of Error, between a sample staristic and its corresponding Popwlation parameter 7 Error does not ingicare a mristare was made | ~ Samples ore variable; two sompies are very, very rarely, Identical — * The distribution of sample means Is the conection of Sample Means gor ali the possible random samples of % particuiar size Cn) thot can be obtained grom a popu lation. ~ Sompies digger from each other T iven random SOMPIE ALIS UMIKeLY that sample | Means would be the some % Sampie means ditger grom each other ~_SOMP\AG ASTHbUtION Ig g istrioUtion OF SIALISTICS CD- foined by selecring oll the possiwle samples oF a specific SIZE FrOM oO population TNE diserivution oF SAMPIE means Is ON example oF sampting distribution, often cated the sampling Aistribution of M (mora teristics of the distrip ution of sample means “The sample means shoutd pil€ up around the popuraricry mean ~The distribution of SAMPIE Means IS approximately Normal in shape ~ The larger the sample size, the closer the sample MENS should be to the population mean (A) fo Distrivution of Sample Means" Distribution of Sample Means! “The central Umit theorem > for any population with MEAN A ANd StANdOId deViONION o, the AiStriourtion oF Sample means for sample size M will have ® Mean Of HmAaNd G standard agviation of = ond will APPFOACH a Normal distribution as nN Spproathes inginity * The shape of the distribution sample means “We SISMiburion of sample means Is almost pereectly NOrMMol if tither Of the folowing 2 condition is sarisgied * tne POPUIGIION From wwich the Samples are selected 13.0 normal diltribution * The number o¢ scares (n) in each Sample is relatively large, Ground 20 oF more * The mean of the distribution of SAMpIe Means: the Expecced value _o¢ M “MEN OF thE AIST idUtION OF the sample Means iS Haw and Mos O vOWWE equal to the mean of the popuration OF SuOres, ~ MEAN of the disttiouttion oF sormple means is called dhe expected value of M “Mis an unviaced statistic * Te syandard error uM ~ VONODINY OF O AriDULION oF SCONES Is Measured by the standord aeviation ~ The standard deviation Of (ME Aurrioution oF sample MEANS 19 COMA the standard error of Mand written om ~ The sraNaard error provides a measure QF HOW much STANCE Is CHpELTEd on AVEFAgE Let WEEN a sample mean (M) and the population mean. (y) “Te Magnitude of the standard ertor * Low og large number, stares that the larger the SAMP AL s\2e (N), the more provable ity that the SAMPIE MON will ye close to the popurstion mean, X Popmarion standard, devigrion othe standard error Scanned with CamScanner 
