What is PeopleAnalyst?

PeopleAnalyst is the front door for people-analytics research: 205+ works indexed and profiled, 40+ citation-grade findings extracted, and peer-reviewed behavioral science translated from academic to actionable — the missing manual for the people analytics you always meant to do.

What is people analytics?

People analytics is not a dashboard. It is behavioral science and statistical inference applied to workforce decisions — a discipline with its own methodology, spanning measurement, organizational design, talent, leadership, and analytics craft.

Why does AI in HR need measurement science?

AI is being deployed in high-stakes people decisions — hiring, performance, attrition — without the measurement science to evaluate whether it works or whom it harms. Construct validity, effect sizes, and criterion validity are the vocabulary for asking an AI vendor the right questions.

How is the research made accessible?

The evidence is indexed and searchable: 205+ works, 40+ citation-grade insight cards, and 8 research arcs, so the right finding reaches the right decision at the right time.

What separates good people measurement from assertion?

Good measurement has a method: construct validity, reliability, and effect-size interpretation are not optional — they are what separates evidence from assertion.

library / lib7b1f02cca98ce424

Why We Sleep Unlocking the Power of Sleep and Dreams

Matthew Walker

In a sentence

A leading neuroscientist reveals the transformative power of sleep, explaining its critical role in learning, health, and longevity, and sounds the alarm on the global sleep-loss epidemic that is silently damaging our lives.

Why We Sleep is an urgent and fascinating exploration of the single most important but least understood aspect of our lives: sleep. Neuroscientist Matthew Walker dismantles the myth that sleep is mere downtime, revealing it as a dynamic and essential process that enhances our ability to learn, memorize, and make logical decisions; recalibrates our emotions; restocks our immune system; and fine-tunes our metabolism. The book exposes the devastating consequences of chronic sleep deprivation—now a global epidemic—linking it directly to major health crises like Alzheimer's disease, cancer, diabetes, and heart disease. Walker not only explains the science behind why we sleep and dream but also provides practical advice on how to reclaim the sleep we so desperately need, arguing that it is the most powerful elixir of life and the most effective thing we can do to reset our brain and body health each day.

The four lenses

Science
Statistics
Systems
Strategy

The model

This is a causal model illustrating the core argument of 'Why We Sleep'. It posits that sleep hygiene behaviors and environmental conditions determine the quantity and quality of sleep achieved. This, in turn, directly influences cognitive, emotional, and physiological functioning. These intermediate states ultimately determine long-term health outcomes and daily performance.

Sleep Hygiene Behaviorsdesign lever

Voluntary actions and routines that promote or inhibit sleep, including maintaining a regular sleep-wake schedule, managing caffeine and alcohol intake, and creating a wind-down routine before bed. These are choices that directly influence sleep opportunity and readiness.

Environmental Sleep Conditionscontextual condition

External factors in the sleep environment that affect sleep quality, primarily ambient light (especially blue light from screens), temperature, and noise. These conditions can either support or disrupt natural sleep processes.

Sleep Architecturepsychological state

The objective quantity and quality of sleep achieved, defined by total sleep time, sleep efficiency, and the cyclical progression through the different stages of sleep (light NREM, deep slow-wave NREM, and REM sleep). This is the direct physiological result of sleep hygiene and environment.

Neurocognitive Functionpsychological state

The effectiveness of core brain processes including attention, learning capacity, memory consolidation, emotional regulation, logical reasoning, and creativity. This state is directly restored and enhanced by achieving sufficient, high-quality sleep.

Physiological Homeostasispsychological state

The stable and healthy regulation of the body's primary systems, including the immune, metabolic (glucose control, appetite hormones), and cardiovascular (blood pressure, heart rate) systems. Sleep is presented as the primary activity for restoring this balance.

Long-Term Health and Longevityoutcome metric

An individual's overall lifetime health, characterized by a reduced risk of chronic diseases (e.g., cancer, Alzheimer's, diabetes, cardiovascular disease) and an increased healthspan and lifespan.

Daily Performance and Well-Beingoutcome metric

An individual's day-to-day effectiveness, productivity, creativity, emotional stability, and safety. This includes performance in the workplace, social interactions, and activities requiring sustained attention, such as driving.

How they connect

sleep hygiene behaviors → influences sleep architecture
environmental sleep conditions → influences sleep architecture
sleep architecture → predicts neurocognitive function
sleep architecture → predicts physiological homeostasis
neurocognitive function → predicts daily performance and wellbeing
physiological homeostasis → predicts long term health and longevity
neurocognitive function → influences long term health and longevity

The story

The reader The reader is a health-conscious individual living in a fast-paced, modern society. They want to maximize their potential—to be more productive, creative, healthy, and happy—but often feel tired, unfocused, and concerned about their long-term well-being.

External problem

Societal norms, demanding work schedules, and pervasive technology consistently prevent them from getting the 7-9 hours of sleep their body and brain need.

Internal problem

They feel fatigued, mentally foggy, emotionally unstable, and anxious about the potential long-term health consequences of their chronic sleep deprivation.

Philosophical problem

It's just plain wrong that our culture glorifies sleep deprivation as a badge of honor and productivity, when it is actually the foundation of our physical and mental health.

The plan

Understand the fundamental science of sleep, including your circadian rhythm, sleep pressure, and the different stages of sleep (NREM and REM).
Learn the profound benefits of sleep for the brain (learning, memory, emotional regulation) and body (immunity, metabolism, cardiovascular health).
Recognize and eliminate the modern factors that are harming your sleep, such as caffeine, alcohol, artificial light, and incorrect room temperature.
Implement the 'Twelve Tips for Healthy Sleep' to establish a consistent and restorative sleep routine.

Success

A longer, healthier life with a significantly reduced risk of major illnesses like cancer, Alzheimer's, and heart disease.
Enhanced cognitive abilities, including better memory, creativity, and focus.
Improved emotional stability, mood, and overall mental well-being.
Increased daily energy, productivity, and physical vitality.

At stake

A shortened lifespan and a diminished quality of life.
A dramatically increased risk of developing numerous chronic diseases and mental health disorders.
Persistently feeling tired, unproductive, and emotionally unstable.
Failing to ever reach one's full potential, both personally and professionally.

Questions this book answers

Why is sleep a non-negotiable biological necessity and not an optional luxury?
What are the distinct functions of NREM and REM sleep for our brain and body?
How does insufficient sleep lead to devastating health consequences like Alzheimer's, cancer, heart disease, and diabetes?
What are the functions of dreaming, and how does it serve as a form of 'overnight therapy'?
What modern-day factors are robbing us of sleep, and what practical steps can we take to improve our sleep quality and quantity?

Glossary

Sleep Hygiene Behaviors: The set of voluntary practices and habits that are conducive to sleeping well on a regular basis. This includes behaviors related to timing (e.g., consistent bedtime), consumption (e.g., avoiding caffeine/alcohol before bed), and pre-sleep routines (e.g., relaxing activities).
Environmental Sleep Conditions: The physical characteristics of the sleep environment that influence the brain's ability to initiate and maintain sleep. Key factors include light exposure (intensity and spectrum), ambient temperature, and noise level.
Sleep Architecture: The objective quantity, quality, and structure of a sleep episode. It encompasses the total duration of sleep and the proportion and cycling of different sleep stages, particularly the balance between restorative deep NREM sleep and REM sleep.
Neurocognitive Function: The state of the brain's higher-order information processing abilities. This includes the capacity for sustained attention, the ability to learn new information, the consolidation of memories, the regulation of emotional responses, and the generation of creative insights.
Physiological Homeostasis: The body's ability to maintain a stable and balanced internal environment across its key biological systems. This includes the proper functioning of the immune system to fight infection, the metabolic system to regulate blood sugar and appetite, and the cardiovascular system to maintain healthy blood pressure and heart function.
Long-Term Health and Longevity: An individual's overall state of physical and mental health across their lifespan, defined by the absence of chronic disease and the duration of life.
Daily Performance and Well-Being: An individual's functional capacity and subjective experience in their daily life. It encompasses professional productivity and creativity, social and emotional functioning, and the ability to perform safety-critical tasks like driving without impairment.