Causal Inference Methods: RCTs vs. Quasi-Experimental Designs
RCTs and the Foundations of Causal Inference
A Randomized Controlled Trial (RCT) earns its privileged status because the researcher dictates treatment assignment through explicit randomization, thereby severing any systematic link between the treatment and unobserved confounders. That design choice ensures “internal validity at list price”: the difference in average outcomes across treatment arms is, by construction, an unbiased estimate of the causal effect, conditional only on compliance and
Read MoreImplementing Core Machine Learning Algorithms in Python
1. Perceptron Algorithm Implementation
The Perceptron is a foundational linear classification algorithm. This implementation uses NumPy for efficient vector operations.
Perceptron Class Definition
import numpy as np, random
class Perceptron:
def __init__(self, eta=0.01, n_iter=50, random_state=1):
self.eta, self.n_iter, self.random_state = eta, n_iter, random_state
def fit(self, x, y):
rgen = np.random.RandomState(self.random_state)
self.w_ = rgen.normal(0, 0.01, 1 Digital Image Processing Fundamentals: Sensors, Color, and Analysis
Introduction to Digital Image Processing
This document covers fundamental concepts in digital image processing, including sensor technology, color models, data representation, and essential image manipulation techniques like normalization, histogram processing, and binarization.
Principle of Operation of the CMOS Sensor
The CMOS (Complementary Metal-Oxide-Semiconductor) sensor works on a similar principle to the CCD. Light falls onto a silicon crystal, forming pixels and generating electrical charges
Read MoreCognitive Processes and Knowledge Types in Second Language Acquisition
Cognitive Processes in Second Language Acquisition (SLA)
This section examines how our mind receives and processes information during language acquisition. It explores how processed information becomes knowledge and functions within our cognitive system.
Types of Knowledge in SLA
Knowledge types discussed include:
- Acquired vs. Learned knowledge
- Declarative vs. Procedural knowledge
- Implicit vs. Explicit learning/knowledge
Both declarative and procedural knowledge are stored in our brain.
How Linguistic Knowledge
Read MoreSemantic Relations: Monosemy, Synonymy, Polysemy, and Antonymy
Semantics: The Study of Word Meaning
Semantics is the science that studies the meaning of words.
Fundamental Semantic Relations
A signifier having only one meaning is called monosemy.
When a signifier corresponds to multiple meanings, we encounter the semantic phenomena of synonymy, polysemy, and homonymy.
1. Synonymy
Synonymy occurs when multiple signifiers share the same meaning.
For example, the words cold and ice are presented as having the same meaning.
Few words are perfect synonyms. Significant variations
Read MoreNetwork Capacity and Routing Optimization Implementation
Algorithm Implementation: executeAlgorithm
This method executes the core network optimization algorithm, setting up the problem, defining constraints, and applying the resulting routing and capacity plan to the NetPlan object.
Method Signature
public String executeAlgorithm(NetPlan netPlan, Map<String, String> algorithmParameters, Map<String, String> net2planParameters)
{Parameter Initialization
The algorithm first parses the required input parameters, defining key constraints and costs:
Read MoreGeological Evolution of the Iberian Peninsula Relief
The current relief of the Iberian Peninsula is the result of a geological history spanning millions of years, characterized by alternating orogenic phases and periods of calm dominated by erosion and sedimentation.
A. Archaic or Precambrian Era (4,000–600 Million Years Ago)
- An arched band emerged from the sea, extending from the northwest to the southeast, formed by schists and gneiss. This band included almost all of present-day Galicia.
- Elevations also arose in isolated points of the Central System
Essential Pharmacology: Mechanisms and Drug Classes
Oral Hypoglycemic Agents (OHAs)
Oral Hypoglycemic Agents (OHAs) are medications taken by mouth to help lower blood sugar levels in people with type 2 diabetes. They work by stimulating the pancreas to produce more insulin, improving the body’s sensitivity to insulin, or slowing down the absorption of glucose from the digestive tract.
Types of Oral Hypoglycemic Agents
Sulfonylureas
These stimulate the pancreas to release more insulin (e.g., glipizide, glyburide).
Meglitinides
Similar to sulfonylureas,
Essential Chemistry Concepts and Atomic Theory Timeline
Fundamental Chemistry Concepts and Definitions
Physical and Chemical Properties
- Physical Property: A description that helps identify a substance.
- Quantitative Characteristics: Characteristics that are measured. They always include a number and a unit.
- Qualitative Characteristics: Characteristics observed with the senses that are described but not measured.
- Characteristic Physical Property: A unique physical property used specifically to identify a substance (e.g., density, melting point).
- Chemical Properties:
World War II Aftermath: Reconstruction and the Cold War’s Genesis
The Impact of World War II
When the Second World War finished, it ravaged Europe and its population, which was decimated. Two new powers emerged: the United States (U.S.) and the USSR. The demographic balance showed around 50 million deaths; nearly half were in the USSR, followed by Germany and Poland.
Consequences of the War
Physical Destruction and Economic Shifts
The physical destruction was immense, affecting cities, infrastructure, and industrial facilities. This destruction caused a reduction