Research Methodology: Sampling, Testing, and Reporting
Part 1: Sampling Design and Sampling Procedure
In research, it is usually impossible, too expensive, or too time-consuming to collect data from every single individual in a population (referred to as a census). Instead, researchers select a smaller, representative subset of that population, known as a sample.
- Population (N): The total collection of all elements that share a common set of characteristics (e.g., all BBA students in a university).
- Sample (n): The actual group chosen from the population
One-Way ANOVA: Concepts, Assumptions, and Applications
Understanding One-Way Analysis of Variance (ANOVA)
One-Way Analysis of Variance (ANOVA) is a statistical technique used to compare the means of three or more independent groups based on a single independent variable (factor).
It is utilized to determine whether there is a significant difference between group averages. In simple terms, One-Way ANOVA helps identify whether different groups behave differently regarding a measurable outcome.
Examples of One-Way ANOVA
- Comparing marks of students from three
Statistical Inference and Hypothesis Testing Practice
Exercise 1: Multiple Choice
1. Different Rejection Rule
- (a) H₁: µ = 90 (< 100) → reject for small X̄ (left tail)
- (b) H₁: µ < 100 → reject for small X̄ (left tail)
- (c) H₁: µ = 90, H₀: µ > 90 → reject for small X̄ (left tail)
All three tests reject on the left tail. Re-examining the options: all are left-tailed. Looking again at (c): H₀: µ > 90 vs H₁: µ = 90. Here, H₁ specifies a value below H₀, so we reject for small values. They all look left-tailed, but (c)
Read MoreEssential R Programming Syntax and Data Analysis Techniques
R Programming Fundamentals
- n <- (x): Store a value in a variable.
- c(): Combine values into a vector.
- as.type(c()): Change data type (e.g., as.numeric, as.character).
- rm(variable): Remove from memory; rm(list=ls()) deletes everything.
- ls(): List all variables in memory.
- ==: Equality operator.
- NaN: Not a Number (undefined mathematical operation).
- NA: Missing value.
- Vector indexing: Use
[x]for a single value or[x:y]for a range.
Conditional Logic and Loops
Marketing Campaign Classification
conversion <Statistical Hypothesis Testing and JMP Analysis
1. Background, Problem Statement & Goals
This section aligns with the 4M framework: Motivation → Method → Mechanics → Message.
A. Define the Business Problem
Clearly explain the question you are trying to answer. Examples:
- How can we estimate home prices?
- Which marketing channel generates the highest sales?
- Does employee experience affect salary?
B. Identify the Response Variable (Dependent Variable)
The response variable is what you are predicting or explaining (e.g., Sales Revenue, Home Price,
Read MorePearson Correlation and Linear Regression Formulas
Pearson Correlation & Linear Regression Cheat Sheet
Pearson Product-Moment Correlation & Linear Regression
Correlation Definition
Correlation measures the strength and direction of a relationship between two variables.
Warning: Correlation does NOT imply causation.
Types of Correlation
| Type | Description | Graph Trend |
|---|---|---|
| Positive Correlation | Variables increase/decrease together | Upward slope |
| Negative Correlation | One increases while the other decreases | Downward slope |
| Zero Correlation | No predictable relationship | Random |