Statistics for Business Intelligence – Multiple Regression

Simple regression deals with predicting a dependent variable using an independent variable using a linear regression equation. In multiple regression analysis there are more than one independent variables or at least one non linear independent variable. Multiple Regression Model :The multiple regression model is of the form.where y = the value of the dependent variable.beta0 … Read more

Statistics for Buiness Intelligence – Chi Square Tests

Chi square tests, namely chi-square goodness of fit test and chi-square test of independence, are used to analyse data that are a frequency distribution of discrete variables. Consider for example, a wine cellar that has four different categories of wine, a frequency distribution of the four varieties of wine can be analysed by such tests.Chi-Square … Read more

statistics for business intelligence – ANOVA

Design of experiments : An experimental design is used to test a hypothesis by modifying one or more variables. The variables may be dependent or independent. Independent variables may be a treatment variable (can be modified) or classification variable (characteristic of the experimental factors, present prior to the experiment and is not modified during the … Read more

statistics for Business intelligence – Inference for 2 populations

Here we consider comparing the statistic from two samples. we would compare the mean, population proportion and variance. The tests used would be the z test and the t- test. Some of the experiments would use independent samples. (members in both the samples are independent of each other)Difference in two means using z-statistic : according … Read more

Statistics for Business Intelligence – Hypothesis testing

Hypothesis is defined in as ‘a proposition assumed as a premise in an argument’. This post explores the various kinds of hypothesis in statistics and methods to test them. Research hypothesis : A statement that is considered the outcome of an experiment or test, before the experiment is undertaken.Statistical hypothesis : This is used … Read more

Statistics for Business Intelligence – Inferential Statistics 1

Inferential statistics is the term given to the branch of statistics that uses the information from the sample to infer the information about the population. For example, given a sample mean , the population mean (also called a parameter) can be determined using inferential statistics. Estimating population mean – Let us first look at estimating … Read more

Statistics for Business Intelligence – Shape

In this post i will discuss the measures of shape used for statistical analysis, specifically skewness and kurtosis. I will also discuss the box and whisker plot. Skewness – A normal distribution is a bell curve that is perfectly symmetric. perfect symmetry implies that the values are distributed equally around the center. a graph is … Read more