Analysing a single statistical variable
Transcription
Analysing a single statistical variable
HDL HOCHSCHULVERBUND DISTANCE LEARNING BUSINESS STATISTICS Götze 1. Auflage 2000 Studienbrief 2 – 030 – 0901 E Analysing a single statistical variable Verfasser: Prof. Dr. Wolfgang Götze Professor für Mathematik, Statistik, Informatik im Fachbereich Wirtschaft an der Fachhochschule Stralsund Übersetzer: Prof. Dr. Wolfgang Götze, Urta Schünemann Fachhochschule Stralsund Der Studienbrief wurde auf der Grundlage des Curriculums für das Studienfach Wirtschaftsstatistik verfasst. Die Bestätigung des Curriculums erfolgte durch den Fachausschuss für das modulare Fernstudienangebot Betriebswirtschaftslehre, dem folgende Professoren angehören: Dr. Albers (FH Magdeburg), Dr. Bathe (HTWS Zittau/Görlitz), Dr. Greife (FH Brandenburg), Dr. Götze (FH Stralsund), Dr. Hannemann (HS Anhalt), Dr. Heger (FHTW Berlin), Dr. Heße (FH Jena), Dr. Hofmeister (FH Erfurt), Dr. John (HTWK Leipzig), Dipl.-Ök. Schindler (FH Merseburg), Dr. Strunz (Westsächsische HS Zwickau), Dr. Teichmann (TFH Wildau), Dr. Witt (HS Wismar). 1. Auflage 2000 Redaktionsschluss: August 2000 2000 by Service-Agentur des Hochschulverbundes Distance Learning mit Sitz an der FH Brandenburg. Das Werk ist urheberrechtlich geschützt. Die dadurch begründeten Rechte, insbesondere das Recht der Vervielfältigung und Verbreitung sowie der Übersetzung und des Nachdrucks, bleiben, auch bei nur auszugsweiser Verwertung, vorbehalten. Kein Teil des Werkes darf in irgendeiner Form ohne schriftliche Genehmigung der Service-Agentur des HDL reproduziert oder unter Verwendung elektronischer Systeme verarbeitet, vervielfältigt oder verbreitet werden. Service-Agentur des HDL (Hochschulverbund Distance Learning) Leiter: Dr. Reinhard Wulfert c/o Agentur für wissenschaftliche Weiterbildung und Wissenstransfer e. V. Magdeburger Straße 50, 14770 Brandenburg Tel.: 0 33 81 - 35 57 40 Fax: 0 33 81 - 35 57 49 E-Mail: kontakt-hdl@aww-brandenburg.de http://www.aww-brandenburg.de Business Statistics Analysing a single statistical variable Table of contents Statistical symbols...................................................................................................................... 4 Table with icons ......................................................................................................................... 5 Literature suggested .................................................................................................................. 7 1 Aims and methods of descriptive statistics ................................................................... 7 1.1 1.2 1.3 1.4 1.4.1 1.4.2 1.5 1.6 Fields of applications ....................................................................................................... 7 History............................................................................................................................. 8 The approach of a statistical survey ................................................................................. 8 Units, variables, values .................................................................................................... 9 Scaling and typing ........................................................................................................... 9 Cross section and longitudinal section ........................................................................... 10 Statistical reliability....................................................................................................... 10 Study objectives and examples for basic terms............................................................... 11 2 Empirical distributions ................................................................................................ 13 2.1 2.2 2.3 2.4 Frequency distribution table........................................................................................... 13 Stick diagrams and polygons.......................................................................................... 13 Grouping data ................................................................................................................ 15 Histogram and empirical distribution function ............................................................... 17 3 Measures of central tendency ...................................................................................... 21 3.1 3.2 3.3 3.4 3.5 3.6 3.7 Mode ............................................................................................................................. 22 Median........................................................................................................................... 22 Arithmetic mean ............................................................................................................ 24 Relations between the several means ............................................................................. 25 Weighted arithmetic mean ............................................................................................. 27 Geometric mean ............................................................................................................. 27 Harmonic mean.............................................................................................................. 28 4 Measures of variability ................................................................................................ 30 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 Range............................................................................................................................. 31 Distance of quartiles ...................................................................................................... 31 Variance ........................................................................................................................ 32 Relations between variance and arithmetic mean ........................................................... 33 Standard deviation ......................................................................................................... 33 Further characteristics of variance and standard deviation ............................................. 34 Relative dispersion......................................................................................................... 35 Further statistical measures ............................................................................................ 35 Summery........................................................................................................................ 37 5 Concentration............................................................................................................... 39 5.1 5.2 Measuring the relative concentration using Lorenz curves ............................................. 40 Gini’s coefficient ........................................................................................................... 43 Analysing a single statistical variable Business Statistics 5.3 5.4 5.5 Measuring the relative concentration for grouped data ...................................................44 Measuring the absolute concentration.............................................................................45 Summery ........................................................................................................................48 6 Indices ...........................................................................................................................51 6.1 6.2 6.2.1 6.2.2 6.2.3 6.2.4 Simple Indices................................................................................................................51 Compounded indices ......................................................................................................52 Price indices ...................................................................................................................53 Set indices ......................................................................................................................54 Sales indices...................................................................................................................55 Stock exchange indices................................................................................................... 55 Solutions of exercises and control questions ...........................................................................59 List of further literature ..........................................................................................................62 Statistical symbols xi observations or values of a variable X for i = 1,...,n aj different values of a variable X for j = 1,...,k Hn (aj) absolute frequency hn (aj) relative frequency Sn (aj) cumulated relative frequencies Fn (x) empirical distribution function of a discrete variable F(x) empirical distribution of a continuous variable gj class limits for classes j = 1,..,q bj width of a class mj midpoint of a class Hj absolute frequency of a class hj relative frequency of a class Sq (j) cumulated relative frequencies of grouped data Fq (x) empirical distribution in the case of grouped data x mod mode x (i) ascending sorted observations x med median xα α-quantile x arithmetic mean x∗ arithmetic mean for grouped data 4 Business Statistics Analysing a single statistical variable _ xw weighted arithmetic mean x harm weighted harmonic mean x geom geometric mean R range ∆ distance of quartiles s 2 mean square deviation from an arithmetic mean v variation coefficient G Gini’s coefficient H Herfindahl’s index P L0,1 Laspeyres’ price index PP0,1 Paasche’s price index Q L Q P 0,1 Laspeyres’ set index 0,1 Paasche’s set index 0,1 Fisher’s Ideal-Index for prices F P F Q 0,1 U0,1 Fisher’s Ideal-Index for sets sales index Table with icons N D E Q O S Note Definition Example Questions Objectives Summary 5