Research methodology basics

 Your sentence accurately summarizes the advantages of Partial Least Squares Structural Equation Modeling (PLS-SEM) . Here's a clear, expanded explanation of each part of the statement: ✅ “PLS-SEM is a variance-based modeling approach…” Variance-based means PLS-SEM aims to maximize the explained variance (R²) in the dependent (endogenous) variables. Unlike Covariance-Based SEM (CB-SEM) , which focuses on reproducing the entire covariance matrix and overall model fit, PLS-SEM emphasizes prediction and explaining target constructs . ✅ “…gained popularity in the fields of management and social sciences…” PLS-SEM is widely used in: Management research (e.g., leadership, organizational behavior) Marketing (e.g., customer satisfaction, brand loyalty) Information systems (e.g., tech adoption models like TAM/UTAUT) Education and psychology Its popularity stems from its flexibility and suitability for exploratory research and theory building , which ...

 The Residual Sum of Squares (RSS) , also known as the Sum of Squared Errors (SSE) , is a measure of the discrepancy between the actual data points and the values predicted by a regression model. 📌 Definition: RSS = ∑ ( Y i − Y ^ i ) 2 \text{RSS} = \sum (Y_i - \hat{Y}_i)^2 Where: Y i Y_i ​ = actual value of the dependent variable Y ^ i \hat{Y}_i ​ = predicted value from the regression model Y i − Y ^ i Y_i - \hat{Y}_i ​ = residual or error term 🎯 What Does RSS Represent? RSS quantifies the total amount of variation in the dependent variable that is not explained by the regression model . A smaller RSS means the model's predictions are closer to actual values → better fit. A larger RSS indicates poor model fit , with more prediction errors. 📊 Where It Fits in Total Variance In regression or ANOVA: Total Sum of Squares (SST) = Explained (SSR) + Residual (RSS or SSE) \text{Total Sum of Squares (SST)} = \...

 The F-Ratio (also called the F-statistic ) is a key concept in ANOVA and regression analysis , used to test whether a model or group of variables significantly explains variation in the dependent variable. 🎯 What is the F-Ratio? The F-Ratio is the ratio of systematic variance (explained by the model or treatment) to unsystematic variance (error or residual variance). In simpler terms: It tells us whether the variation explained by the independent variables is significantly greater than the unexplained (random) variation. 🧮 F-Ratio Formula In ANOVA or regression: F = Mean Square Between (MSB) Mean Square Within (MSW) or F = MSR MSE F = \frac{\text{Mean Square Between (MSB)}}{\text{Mean Square Within (MSW)}} \quad \text{or} \quad F = \frac{\text{MSR}}{\text{MSE}} ​ Where: M S R =   Mean Square due to Regression (Systematic) M S E = S S E n − k − 1 MSE = \frac{SSE}{n - k - 1} ​ → Mean Square Error (Unexplained) 📌 W...

 Great question! Degrees of Freedom (df) is a core concept in statistics, especially in regression , ANOVA , and hypothesis testing . 🎯 What is Degrees of Freedom (df)? Degrees of Freedom represent the number of independent values in a calculation that are free to vary after certain restrictions (like means) have been applied. In simple terms: It's the number of values in a dataset that can change without violating a given constraint . 🧠 Why It Matters Degrees of freedom are used to: Calculate variances and standard errors Determine the critical values in t-tests , F-tests , and chi-square tests Assess the validity of models (like in regression or ANOVA) 📊 Degrees of Freedom in Common Contexts 1. Sample Variance When calculating variance: s 2 = ∑ ( X i − X ˉ ) 2 n − 1 s^2 = \frac{\sum (X_i - \bar{X})^2}{n - 1} ​ The mean X ˉ \bar{X} X ˉ uses up 1 degree of freedom . So the df = n - 1 (where n n n is the number of observations) 2. A...

 Certainly! The Sum of Squares (SS) is a fundamental concept in statistics, especially in regression and ANOVA . It measures variability —that is, how much values differ from a mean or predicted value. 🔍 What Is Sum of Squares? Sum of Squares quantifies the total variation in a dataset by summing the squared deviations from a reference value (usually the mean or predicted value). The general form is: SS = ∑ ( X i − Reference Value ) 2 \text{SS} = \sum (X_i - \text{Reference Value})^2 Why squared? To avoid cancellation of positive and negative deviations To give more weight to larger deviations 🎯 Types of Sum of Squares in ANOVA/Regression 1. Total Sum of Squares (SST) Measures the total variation in the dependent variable Y Y Y Compares each actual value to the grand mean Y ˉ \bar{Y} Y ˉ S S T = ∑ ( Y i − Y ˉ ) 2 SST = \sum (Y_i - \bar{Y})^2 2. Explained Sum of Squares (SSR) — also called Regression SS or Between-Group SS Measures the vari...