Statistics

                                         Sampling & Sampling Distribution    Definition:   Probability sampling   is defined as a  sampling  technique in which the researcher  chooses  samples  from a larger population using a method based on the theory of  probability .  For a participant to be considered as a  probability sample , he/she must be selected using a  random selection. 4 types of probability sampling : There are four main types of probability sample. Simple random sampling . In a simple random sample, every member of the population has an equal chance of being selected. ... Systematic sampling . ... Stratified sampling . ... Cluster sampling Advantages of Probability Sampling: The absence of systematic error and sampling bias. Higher level of  reliability  of research findings. Increased acc...

  Sampling & Sampling Distribution Population Parameter  :                                 A measure of location or a measure of dispersion is called a parameter if it describes a  population. One seldom has data for entire population and hence one rarely is able to calculate population  parameters. Characteristics of the part infers Characteristics of the whole. Standard Notation :    Sample statistics :   It refers to a characteristics of  a sample. It is denoted by lower case roman  letter. Population Parameter :  It  refers to a characteristics of as sample. It is denoted by lower case Greek letters.                         Selection Bias :                         Selection bias when some part of target population is not in...

 SAMPLING AND SAMPLING DISTRIBUTIONS Introduction Sampling is pre-requisite of statistical inference. Sample data is used to find value of the sample  statistics which is used to estimate corresponding unknown population parameter. Sampling is  basically of two types namely probability sampling and non probability sampling. sampling design  comprises two things namely sampling technique and size of the sample. Basic Terms population:  The population is the entire group of individuala or objects under consideration. Target population :   The complete collection of observstions we want to study is called target  population. Sampled population :  The population from which the sample is taken is called sampled population. Element : An element is a single member of a population. Sample : Sample is a portion chosen from the population. The sample is a part or subset of population.  Information is obtained only from the cases included in the sample....