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...
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...
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...
