Download Statistics: An Introduction to Data Collection, Organization, and Analysis and more Lecture notes Mathematics in PDF only on Docsity! STATISTICS Chapter 1 Introduction 1.1 1.2 1.3 1.4 1.5 Division of Statistics Parameter and Statistics Variables 1.3.1 Discrete Variables 1.3.2 Continuous Variables 1.3.3 Independent and Dependent Variables Levels of Measurement 1.4.1 Nominal Level 1.4.2 Ordinal Level 1.4.3 Interval Level 1.4.4 Ratio Level The Summation Notation, Sigma Chapter 1 Introduction Every day, we experience statistics. Social weather stations would evaluate the president's performance based on surveys. Sports journalist would explain how a basketball player become the Year’s MVP based on statistical points. The university Registrar would announce the year’s enrollment increase or decrease. Statistics is the branch of mathematics that deals with the collection, organization, preparation, computation and interpretation of the data. Sources data can range from house-to-house surveys to the radar signals of the sum. After these data are collected, statistical methods and tools are applied to produce meaningful output within the form of TOP 40charts, NCEE Grades, or Stock Exchange reports. 0 DIVISION OF STATISTICS The science of statistics has two main divisions: Descriptive and inferential. Differential statistics deals with the collection, organization, presentation, and computation of data to describe the samples under investigation. Inferential statistics gives information, inferences and implications regarding the population by studying its representative samples. In statistics, the totality of objects or of a set is referred to as population, while a small representative cross-section of this population is called sample. The population can be all the songs played in the radio, all respondents of social weather station's, presidential survey's, or the university enrollment for the last 10 years. Since the bulk of data is difficult to handle in its totality, the sampling method is utilized. Sampling method is the process of choosing a representative part of the population the sample obtained is then used in inferential statistics to reach conclusions of detailed reliability about the given population. 0 PARAMETER AND STATISTICS A parameter is some numerical or nominal characteristic of a population. An example is the mean IQ score of all grade one pupils in the CEU integrated school. A statistic is a numerical or nominal characteristic of sample. The mean IQ score of 50 first graders is a statistic and so the observation that all are female. A parameter constant, it does not change unless the population itself changes. Only one number can be the mean of population is un measurable, so we use statistics as an estimate of the parameter. O Variables (read as: the summation of all x subs i’s, | ranging from 1 to 80) which means all the scores X, + X, + X3+ X,= .... Xgo are to be added in the rotation, i is called the subscript. If we want to add all the given scores, Xj, Xo, X3...... X,we simply write n zx, X=i no where Xi means the sum of X, + X, ...X,. the subscript however, may be omitted if ambiguity will result. Just write =X.
