# Statistics 1

 Data any unordered list information list ordered in some way Two types of statistics Descriptive or inferential descriptive statistics when large amounts of data that must be summarised and presented to the public in a way people can understandeg bar charts, pie charts, averages inferential statistics when statisticians try to predict or forecast based on responses from a small group types of data categorical and numerical types of categorical data ordinal (can be ordered)nominal (cannot be ordered) types of numerical data continuous (can be one of an infinite number of values within a given range)discrete ( certain/definite values) primary data is collected by or for the person who is going to use it two types of primary data observational study and designed experiment observational study researcher collects the information of interest but does not influence the eventsinclude case-control studies where one group is the control and the other has the condition designed experiment treatment applied to a group of subjects and then observe the effects of the treatment on the subjectsexplanatory variable; the variable being testedresponse variable; the effect of the variable sample survey opinion polls which are designed to ask questions of a small group of people in the hope of learning something about the entire population population entire group being studied census is a survey of the whole population sample is a group that is selected from the population in order to gather information parameter is a numerical measurement describing some characteristics of a population. It is a fixed number, but in practice its value is unknown statistic is a numerical measurement describing some characteristics of a sample. The statistic can change from sample to sample. bias in sampling samples that are not representative of the populationeg voluntary response samples simple random sample a sample of sizeĀ n is selected in such a way that every possible sample of sizeĀ n from the population has an equal chance of being selected to select a stratified random sample, first divide the population into at least two different subgroups so that the individuals or subjects within each subgroup share the same characteristics. Then a simple random sample is drawn from each subgroup and combined to form the full sample systematic random sample 1.Assign numbers to population2.population/sample to find interval3.choose number between one and the interval (eg interval is 20, and the number is chosen is 13) Start from 13 and select every 20th number from 13 Authorjoneritte ID313729 Card SetStatistics 1 Descriptionstatistics theory Updated2016-01-04T19:22:21Z Show Answers