By RAFAŁ WAŚKO (Predictive Solutions) The power of a test is the probability of detecting a statistically significant effect when one actually occurs in the population under study. Without adequate test power, we may make a type II error, meaning that the analyst will...

By WIKTORIA KORYGA (Predictive Solutions) Kurtosis and skewness are measures of asymmetry that describe such properties as the shape and asymmetry of the distribution under analysis. They provide us with information on how the values of the variables deviate when...

By RAFAŁ WAŚKO (Predictive Solutions) The Student's t-test group is used to compare two groups of results, measured by the arithmetic mean, against each other. WHAT DO THE T-TESTS TEST? These types of tests will be useful to us when we want to determine whether the...

By RAFAŁ WAŚKO (Predictive Solutions) The chi-square test of independence is one of the most popular statistical tests. It is used to check whether there is a statistically significant relationship between two qualitative variables. It is based on comparing the...

By RAFAŁ WAŚKO (Predictive Solutions) Customer Effort Score (CES), along with Net Promoter Score (NPS), and Customer Satisfaction (CSAT), is one of the key indicators related to clients' satisfaction. All these three indicators are intended to understand the moods of...

By NATALIA GOLONKA (Predictive Solutions)   The Customer Satisfaction Index (CSI) is a method used in marketing to evaluate client satisfaction derived from products or services being provided by a company or organisation.Using a short questionnaire it is...

By RAFAŁ WAŚKO (Predictive Solutions) The main idea of regression is to predict the value of a dependent variable (otherwise known as predictor, explained variable) based on one or more independent variables (called predictors, explanatory variables). The simplest...

By RAFAŁ WAŚKO (Predictive Solutions) Researching customer satisfaction and loyalty is currently an inseparable part of running a business that is focused on developing and building their advantage over competitors. Currently, the standard in this respect is the NPS...

By RAFAŁ WAŚKO (Predictive Solutions) Column and bar charts have long been some of the most popular ways to visualize data. Before you decide to use any of them, it's worth taking a closer look at them. COLUMN AND BAR CHARTS Column and bar charts are one of the...

By JOANNA SARATA (Predictive Solutions) WHEN IT COMES TO CHARTS ‘LESS’ IS NOT NECESSARILY BETTER AND ‘MORE’ CAN OFTEN LEAD TO MORE FUNCTIONAL DATA VISUALISATION. I am not advocating a revolution in chart architecture but encourage you to ponder a more effective use of...