Next-in-line-Effect
When you are so anxious about being next that you cannot remember what the person just before you in line says, but you can recall what the other people around you say.
Spacing Effect
We retain information better when we rehearse over time.
Serial Position Effect
When you recall is better first and last items on a list, but poor for the middle.
Memory
the basis for knowing your friends, neighbors, the English language, the national anthem, and yourself.
The Phenomenon of Memory
Any indication that learning has persisted over time. It is our ability to store and retrieve information.
Flashbulb Memory
A unique and highly emotional moment may give rise to a clear, strong, and persistent memory. However, this memory is not free from errors.
Encoding
Requires that you select some stimulus event (from the vast array of inputs assaulting your senses).
Storage
involves the retention of encoded material over time.
Retrieval
accessing the information and bringing it to consciousness.
Sensory Memory
the most fleeting of the 3 stages
-typically holds sights, sounds, smells, textures, and other sensory impressions for only a fraction of a second.
Working Memory (Short-term)
takes info from sensory register and connects it with items already in long-term storage
Long term Memory
receives info from working (STM) and can store it for much longer periods of time
Problems with the model
1) Some information skips the first 2 stages and enters long-term automatically
2) We select information (through attention) that is important to us.
3) The nature of short-term memory is more complex
Maintenance Rehearsal
repeating info to yourself over and over again
-serves well for maintaining info. Temporarily in working memory.
Elaborative Rehearsal
information is repeated and actively connected to knowledge already stored-better strategy for getting info into long-term memory
Chunking
organizing pieces of information into a smaller number of meaningful units of chunks.
Hierarchy
Complex information broken down into broad concepts and further subdivided into categories and subcategories
George Sperling (1960)
found that this stage of memory holds far more info than ever reaches consciousness
Ionic Memory
a momentary sensory memory of visual stimuli; photographic or picture image fleeting
Echoic Memory
momentary sensory memory of auditory stimuli; sounds/words better than iconic
Long-term Potentiation (LTP)
refers to synaptic enhancement after learning.
-An increase in neurotransmitter release or receptors on the receiving neuron indicates strengthening of synapse
Stress Hormones and Memory
Heightened emotions (stress-related or otherwise) make for stronger memories. Continued stress may disrupt memory
Explicit Memory
refers to facts and experiences that one can consciously know and declare
Implicit Memory
involves learning an action while the individual does not know or declare what she knows.
Hippocampus
a neural center in the limbic system that processes explicit memories
Cerebellum
a neural center in the hind-brain that processes implicit memories
Priming
the implicit memory effect in which exposure to a stimulus influences response to a later stimulus.
-an increase sensitivity to certain stimuli due to prior experience. Priming is believed to occur outside the conscious awareness
Tip of the Tongue Phenomenon (TOT)
the inability to recall a word while knowing that it is in memory.
Forgetting
An inability to retrieve information due to poor encoding, storage, or retrieval.
Encoding failure
we cannot remember what we don't encode
Seven sins of forgetting
1) Absent-mindedness
2) Transience
3) Blocking
4) Misattribution
5) Suggestibility
6) Bias
7) Persisitance
Absent- mindedness
inattention to details produce encoding failure
Transience
storage decay over time (fading memories)
Blocking
Interference causes forgetting inaccessibility of stored information(TOT; one item acts as an obstacle to accessing and retrieving another memory).
Misattirbution
Confusing the source of information; memories associated with the wrong times; place or person
Suggestibility
the distortion of memory by suggestion or misinformation ( a leading question later becomes a false memory)
Bias
Belief-colored recollections; the influence of personal beliefs, attitudes and experiences on memory
Persistence
unwanted memories; when we can't forget.
Storage decay
poor durability of stored memories leads to their decay.
Interference
Learning some new information may disrupt retrieval of other information.
Retrieval failure
Although the information is retained in the memory store, it cannot be retrieved
Proactive interference
a cause of forgetting by which previously stored information prevents learning and remembering new information.
Retroactive interference
a cause of forgetting by which newly learned information prevents retrieval of previously stored material.
-Sleep prevents this. it leads to better recall
Motivated forgetting
People unknowingly revise their memories.
Repression
A defense mechanism that banishes anxiety-arousing thoughts, feelings, and memories from consciousness.
Why do we forget?
Forgetting can occur at any memory stage. WE filter, alter, or lose much information during these stages
Memory construction
While tapping our memories, we filter or fill in missing pieces of information to make our recall more coherent.
Misinformation Effect
Incorporating misleading information into one's memory of an event.
Source Amnesia
Attributing an event to the wrong source that we experienced, heard, read, or imagined.
False Memory Syndrome
A condition in which a person's identity and relationships center around a false but strongly believed memory of a traumatic experience, which is sometimes induced by well- meaning therapists.
Improving memory
1) Study repeatedly to boost long-term recall
2) Spend more time rehearsing or actively thinking about the material
3) Make material personally meaningful
4) use memory devices
5) Activate retrieval cues- mentally recreate the situation and mood
6) Recall events while they are fresh- before you encounter misinformation
7) Minimize interference
Memory devices
-associate with peg-words- something already stored
-make up a story
-chunk
Minimize interference
1)test your knowledge
2) Rehearse and then determine what you do not yet know
Pavlov-Classical conditioning
Organism comes to associate 2 stimuli.
A neutral stimulus that signals an unconditioned stimulus begins to produce a response that anticipates and prepares for the unconditioned stimulus.
Unconditioned Stimulus (UCS/US)
stimulus that unconditionally-automatically and neutrally- triggers a response
Unconditioned response
unlearned, naturally occurring response to the unconditioned stimulus
Conditioned Stimulus
originally irrelevant stimulus that, after associations with an unconditioned stimulus, comes to trigger a conditioned response.
Conditioned Response
learned response to previously neutral conditioned stimulus.
Acquisition
the initial stage in classical conditioning in which a association between a neutral stimulus and an unconditioned stimulus takes place.
Extinction
when the US does not follow the CS, CR begins to decrease and eventually causes extinction.
Spontaneous Recovery
After a rest period, an extinguished CR spontaneously recovers, but of the CS persists alone the CR becomes extinct again.
Generalization
Tendency to respond to a stimuli similar to the CS
-Toddlers taught to fear moving cars in the street similarly respond to trucks and motorcycles.
Discrimination
the learned ability to distinguish between a conditioned stimulus and other stimulus that do not signal an unconditioned stimulus.
Operant Conditioning
a form of behavioral learning in which the probability of a response is changed by its consequence (stimuli that follow the response)
Shaping
Procedure in which reinforcers guide behavior towards the desired target behavior through successive approx.
Positive Reinforcement
a stimulus presented after a response and increasing the probability of the response happening again.
-increases behavior
Negative Reinforcement
the removal of an unpleasant or aversive stimulus, contingent on a particular behavior.
-increases behavior by stopping or reducing negative stimuli such as a shock; annoying seat-belt noise.
Primary reinforcer
an innately reinforcing stimulus like food or drink.
Conditioned/Secondary reinforcer
A learned reinforcer that get its reinforcing power through association with the primary reinforcer.
Immediate Reinforcer
A reinforcer that occurs instantly after a behavior. A rat gets a food pellet for a bar press.
Delayed reinforcer
A reinforcer that is delayed in time for a certain behavior. A paycheck that comes at the end of a week.
Skinner
developed the operant chamber, or skinner box, to study operant conditioning.
Fixed- Ratio
Reinforces a response only after a specified number of responses; response rate is usually high.
Example of Fixed-ratio
Piecework pay-suppose you own a tire factor and you pay each worker a dollar for every 10 tires produced
Variable- Ratio
The number of responses required for reinforcement varies from trail to trail. This is hard to extinguish because of the unpredictability. Response rate is the highest.
Example of Variable-ratio
Telemarketers-they never know how many calls they must make before they get the next sale-less predictable
Fixed- interval
Reinforces a response only after a specified time has elapsed; time period between rewards remain constant. Results in low response rate.
Examples of Fixed-interval
-Students who studies for a weekly quiz
-receiving a monthly paycheck
Variable-interval
Most unpredictable of all; time interval between rewards varies; response con be low or high steady responses
Examples of Variable-interval
Fishing, pop quiz, random visits
Positive punishment
presenting an unpleasant stimulus after a response or behavior
Negative punishment
removing a reinforcing stimulus after a response/behavior
Latent learning
being able to navigate quickly for a reward than the organism who haven't seen the reward, despite the lack of reinforcement.
Cognitive map
based in latent learning, being able to navigate directional in different ways without thinking about it.
Tolman
proposed the idea of cognitive maps and latent learning by working with rats in a maze.
Modeling
the process of observing and imitating a specific behavior
Mirror neurons
they are found in the frontal lobe of the brain; they fire when performing certain actions or when observing what another is doing.
Bandura
-pioneer in research on observational learning
-Bobo doll study indicated that individuals learn through imitating others who receive rewards and punishments
90-minute cycles
we go through various stages of sleep
Rhythm of sleep
Circadian rhythms occur on a 24-hour cycle and include sleep and wakefulness, which are disrupted during transcontinental flights.
-our thinking is sharpest and memory most accurate when we are at our daily peak on circadian arousal.
Awake and Alert
During strong engagement, the brain exhibits low amplitude and fast, irregular beta waves (15-30 cps). An awake person involved in a conversation shows shows beta activity.
Awake but Relaxed
When an individual closes his eyes but remains awake, his brain activity slows down to a large amplitude and slow, regular alpha waves (9-14 cps). A meditating person exhibits an alpha brain activity.
Sleep stages 1-2
During early, light sleep the brain enters a high-amplitude, slow, regular wave form called theta waves (5-8 cps).
A person who is daydreaming shows theta activity.
you may experience hypnotic sensations during stage 1.
Sleep stages 3-4
During deepest sleep, brain activity slows down. there are large- amplitude. slow delta waves (1.5-4 cps)
-heart rate and breathing rate slows down
REM Sleep (paradoxical sleep)
After reaching the deepest sleep stage, the sleep cycle starts moving backward towards stage 1. although still asleep, the brain engages in low-amplitude, fast and regular beta waves (15-40 cps).
A person during this sleep experiences rapid eye movement and reports vivid dream.
Over the course of an average night's sleep, most people make the circuit (stages) 4-6 times.
Insomnia
Recurring problems in falling or staying asleep.
Somnambulism
Sleepwalking or sleep talking
-genetic
Nightmares
Frightening dreams that wake a sleeper form REM
Night terrors
sudden arousal from sleep with intense fear accompanied by psychological reactions that occur during stage 4.
Narcolepsy
Overpowering urge to fall asleep that may occur while talking or standing up.
Sleep apnea
Failure to breathe when asleep. After an airless minute decreased blood oxygen causes a person to wake up.
Wish fulfillment
Dreams provide a psychic safety value to discharge unacceptable feeling.
-Dreams manifest content may also have a symbolic meaning (latent content) that signify our acceptable feelings.
Information Processing
Dreams may help sift, sort, and fix a days experiences in our memories.
-dreams may relate to life stressors that have found their way into you sleeping thoughts
Activation-synthesis theory
suggests that the brain engages in a lot of random neural activity. Dreams make sense of this activity
Hypnosis
A social interaction in which one person suggests to another that certain perception, feeling, thoughts, or behaviors will spontaneously occur.
Psychoactive Drug
A chemical substance that alters perceptions and mood (effects consciousness).
Depressants
Drugs that reduce neural activity and slow body functions.
1) Alcohol
2)Barbituates
3) Opiates
Alcohol
affects motor skills, judgement, and memory... and increase aggresiveness while reducing self awareness.
-slows down body processes
Barbibtuates (Tranquilizers)
Drugs that depress the activity of the central nervous syestem, reducing anxiety but impairing memory and judgement.
Opiates
Opium and its deratives.
-depress neural activity, temporarily lessening pain and anxiety
-brain eventually stops prodicing its own endorphins causing extreme discomfort of withdrawl.
Stimulants
drugs that exite neural activity and speed up body functions.
1) CAffenie
2) Nicotine
3)Cocaine
4)Ecstasy
5)Amphetamines
6)Meth
Caffeine and Nicotine
increase heart and breathing rates and other autominic functions to provide energy.
Amphetamines
stimulate neural activity causing accelerated body functions and associated energy and mood changes, with devasting effects.
Methamphetamine (Meth)
(speed)with the use over time it lowers dopamine levels, leaving the user with permanently depressed functioning
Ecstasy (MDMA)
a stimulant and mild hallucinogen. It produces a euphoric high and can damage serotonin-producing neurons, which results in a permanent deflation of mood and impairment of memory.
Cocaine
induces immediate euphoria (15-30 mins) followed by a crash. Crack, a form of cocaine, can be smoked, other forms can be sniffed or injected.
-rush depletes brain supply if dopamine, serotonin,norepinephrine causing agitated depressoin
Hallucinogens
are psychedelic (mind-manifesting) drugs that distort perception and evoke sensory images in the absence of sensory input.
LSD
powerful hallucinogenic drug that is also known as acid.
THC
is the major active ingredient in marijuana that triggers a variety of effects, including mild hallucinogens.
Sensation
a process by which our sensory receptors and nervous system receive and represent stimulus energy.
Perception
a process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
Pain
our body's way of telling us something has gone wrong
Gate-control Theory
theory that the spinal cord contains neurological "gate" that blocks pain signals or allows them to pass on to the brain.
-"gate" opened by activity of pain signals traveling up small nerve fibers
-"gate" closed by activity in larger fibers or by information coming from the brain.
Top-down processing
information processing guided by higher-level mental processing
-as when we construct perceptions drawing on our experience and expectations
Bottom-up processing
analysis that begins with the sense receptors and works up to the brain's integration of sensory information
Signal detection theory
Predicts how and when we detect the presence of a faint stimulus amid background stimulation
-assumes that there is no single absolute threshold
-detection depends partly in person"s: experience, expectations, motivation, and level of fatigue
Weber'slaw
to perceive as different, 2 stimuli must differ by a differ a constant min. percentage.
-light intensity: 8%
-weight: 2%
-tone frequency: .3%
Absolute Threshold
min. stimulation needed to detect a particular stimulus 50% of the time.
Difference Threshold
min. difference between 2 stimuli required for detection 50% of the time.
- just noticeable difference (JND)
Parallel processing
processing of several aspects of a problem simultaneously
Young- Helmholtz Trichromatic Theory
Simply states the retina has 3 types of color receptors.
Opponent- process theory
theory that opposing retinal processes enable color vision (cells in visual system). Complementary pairs.
Visual information processing
information form the retina's receptor cones and rods is received and transmitted by the ganglia cells, whose axons make up the optic nerve, which shoots information to the brain.
Place Theory
different sound waves trigger activity at different places along the cochleas basilar membrane
Frequency theory
suggest an alternative explanation. whole basilar membrane vibrates with the incoming sound wave, triggering neural impulses to the brain of the same rate as the sound wave.
Taste
is a chemical sense.
-taste receptors reproduce themselves every week or so (tongue burn)
-as you get older the number of taste buds decreases; as does your taste sensitivity.
Smell
a chemical sense.-Olfaction receptors recognize odors individually
-our ability to identify scents peaks in early adulthood and gradually declines.
Gestalt- an organized whole
when vision competes with our other senses, vision usually wins- a phenomenon called visual capture
-We organize it. Gestalt psychologists showed that a figure formed a "whole" different than its surroundings.
Depth Perception
ability to see objects in three dimensions
-allows us to judge distance
Binocular Cues
help the brain compute distance
-retinal disparity and convergence
Retinal disparity
Images form 2 eyes differ. "Finger sausage"
Convergence
Neuromuscular cues. when 2 eyes move inward (towards the nose) to see near objects and outward (away from nose) to see faraway
Monocular cues
available to each eye separately
Interpostion
closer object blocks distant object
- objects that occlude (block) other objects tend to be perceive as closer
Relative Clarity
hazy object seen as more distant
- because light from distant objects, we perceive hazy objects to be far away than those objects that appear sharp and clear.
Texture gradient
indistinct (fine) texture signal an increasing distance.
-coarse= close
-fine= distant
Relative Height
higher objects seen as more distant
- in our field of vision to be farther away than those that are lower
Relative motion
closer objects seem to move faster
-fixation point
Linear perspective
Parallel lines appear to converge in the distance. The more the lines converge, the greater their perceived distance
Light and Shadow
Nearby objects reflect more light into our eyes than more distance objects. Given 2 identical objects, the dimmer one appears to be farther away.
Relative size
how big and close something is
Motion perception
objects traveling towards us grow in size and those moving away shrink in size. The same is true when the observer moves to or from an object.
Phi Phenomenon
When lights flash at a certain speed they tend to present illusions of motion.
Perceptual constancy
perceiving objects as unchanging even as illumination and retinal image change
-color, shape, and size
Lightness constancy
We perceive an object as having a constant lightness even while its illumination varies
Color constancy
Perceiving familiar objects as having consistent color even when changing illumination filters the light by the object
Crystallized Intelligence
one's accumulated knowledge and verbal skills
- tends to increase with age
Fluid Intelligence
ones ability to reason speedily and abstractly
-tends to decrease during late adulthood
Zygote
first stage of prenatal development
-attaches to uterine wall and forms a placenta through which nourishment passes
Embryo
after 2 weeks, the zygote develops into this.
- last 6 weeks
- heart begins to beat and th organs begin to develop
Fetus
after 9 weeks, by the 6th month, the stomach and other organs have formed enough to survive outside the mother.
- at this time the baby can hear sounds and respond to light.
Assimilation
interpreting one's new experience in terms of one's existing schemas
- mental process that modifies new schemas
Examples of assimilation
-A toddler may call all 4 legged animals doggies
- An infant will suck a bottle the same way he or she sucked a breast
Accomodation
adapting one's current understanding to incorporate new information
Sensorimotor stage
Children give mainly reflexive or motor responses to stimulation
- very little thinking involved
- coordination of their body parts to grasp and explore attractive objects
-- avoidance of things they dislike
Object permanence
the awareness that things continue to exist even when no perceived
Pre-operational stage
The ability to represent objects mentally.
Emerging sense of self as distinctive form other people and objects in the environment.
- the ability to solve simple problems using mental representation
Egocentrism
the inabilty to realize that there are other view points beside one's own
Pre-operational stage: Conservation
being aware that there are 2 glasses that have the same amount of liquid. however, when the liquid is poured into a taller narrow glass: the indication is that there is more liquid in the taller one.
Concrete Operational stage
Children can now understand that the short glass hols the same amount as the tall narrow glass.
Conservation
understanding that the thought properties of an object or substance do not change when the appearances change, but nothing is added or taken away.
Attachment
an emotional tie with another person
- shown in younger children by their seeking closeness to the caregiver and displaying distress on separation
Harlow's Experiment
Reared monkey with 2 artificial mothers: one with a bare wire cylinder with a wooden head and an attached feeding bottle; the other with no bottle but covered with foam rubber and wrapped with cloth
-monkeys preferred contact with the comfortable mother, while feeding from the nourishing wire mother.
Imprinting
Process by which certain animals form attachments during a critical period very early in life.
-children become attached to what they've known
-ex. Watching the same movies
Authoritative
- both demanding and responsive
- set rules, but explain reasons and encourage open discussion
Authoritarian
Parents impose rules and expect obedients
Permissive
Submit to children s desires, make few demands, use little punishment
Kohlberg
sought to describe the development of moral reasoning
- his findings led him to believe that as we develop intelligence, we pass thru 3 basic levels of moral thinking
Kohlberg's moral ladder
As moral development progresses, the focus of concern moves from the self to the wider social world.
Erik Erikson
stated that each stage of life has its own psychological task.
- a crisis that needs resolution
Erikson's stages of psychological development
Identity
One sense of self
-the adolescents task is to solidify a sense of self by testing and integrating various roles
Intimacy
the ability to form close, and loving relationships
-a primary developmental task in late adolescence and early childhood
Behavior Genetics
study of the relative power and limits of a genetic and environmental influences on behavior
Twin studies
Identical twins: show remarkable similarities in: Intelligence, temperament, gestures, posture, and pace of speech
-can be genetically influenced
Fraternal twins and other sib;ings show fewer similarities which suggest that heredity forces are at work.
Temperament
A person's characteristic emotional re-activity and intensity
- EX. Fidgety, easygoing, quiet, placid, intense, unpredictable, cheerful, relaxed.
Molecular Genetics
the sub-field of biology that studies the molecular structure and function of genes.
Evolutionary Psychology
the study of behavior and the mind, using principles of natural selection.
Argument of critics vs. Brouchard
-the fact that twins reared together typically are more alike than those reared a part provides further testimony to the effect of environment.
-neither heredity nor environment ever acts alone to produce behavior or mental processes.
-they always interact
-from a developmental perspective, heredity and environment work together throughout a person's life.
Adoption studies
adopted children tend to resemble their biological parents in their personality (thinking, feel, acting), and their adoptive parents in their values, attitudes, manners, faith, and politics.
Medulla
Base of the brain-stem
-controls heart beat and breathing
Reticular Formation
a nerve network in the brain-stem that plays an important roll in controlling arousal and the ability to focus attention
Thalamus
the brain's sensory switch board, located on top of the brain stem
-Receives sensory information in the cortex and transmits replies to cerebellum and medulla
Cerebellum
- the "little brain" attached to the rear of the brain-stem.
- it helps coordinate voluntary movement and balance
Limbic System
- a doughnut- shaped system of neural structures at the border of the brain-stem and cerebral hemispheres
- associated with emotions and drives
- includes the hypothalamus, hypocampus, and amygdala
Amygdala
- 2 almond- shaped neural clusters that are components of the limbic system
- emotional control center
- Memory
Hypocampus
involved in memory processing
Hypothalamus
Neural structure lying below the thalamus; directs several maintenance activities
-hunger, thirst, body temperature, and sexual arousal
Helps govern the endocrine system via the pituitary gland
Is linked to emotion
Frontal lobe
involved in speaking and muscle movements and in making plan and judgement
- contains Broca's area
Parietal Lobe
include the sensory cortex
Occipital lobe
include the visual areas, which receive visual information from the opposite visual field
- Right half of each retina goes to left occipital lobe and Vice versa.
Temporal lobe
include the auditory areas
-contains Wernicke's area (Speech/language development)
Specialization and Integration
Brain Plasticity
The ability for our brains to form new connections after the neurons are damaged
-the brain's capacity for modification, as evident in brain reorganization following damage
- the younger you are the more plastic your brain is
William James
Wrote the principles of Psychology and discussed functionalism
- Focused on how mental and behavioral processes enable the organism to adapt, survive, and flourish
- in reality these ideas don't have much impact on how psychologists think today.
William Wundt
first psychological laboratory and his grad. student Edward Titchener's concept of introspection in Germany 1879.
- Looking inward to discover the elements of mind.
Psychoanalysis
The wave of thinking started by Freud
-we protect ourselves from our real feeling by using defense mechanisms
Psychodynamic perspective
Focuses on the unconscious mind.
We are motivated primarily by the energy of irrational desires generated in our unconscious minds
- we repress many of our true feelings and are not aware of them
- in order to get better, we must bring forward the true feelings we have in our unconscious.
Behavior Perspective
Focuses on observable behaviors while putting feelings to the side.
- we behave in ways because we have been recondition to do so.
- To change behaviors, we have to recondition the client
Humanist Perspective
Our actions are hugely influenced by our need for personal growth and by our need for personal growth and fulfillment
- Happiness is defined by the distance between our "self- concept" and "ideal self"
Cognitive Perspective
Focuses on how we encode, process, store, and retrieve information
- Cognitive therapists attempt to change the way you think
Nature- Nuture Controversy
the relative contribution that genes and experience make to development of psychological traits and behaviors
Industrial/organizational psychologists
study and advise on behavior in the workplace
Hindsight Bias
the "I-knew-it-all-along" phenomenon
-After learning the outcome of an event, many people believe they could have predicted that very outcome
The Hawthorne Effect
But even the control group may experience changes
- just the fact that you know you are in an experiment can cause change
Independent Variable
a factor manipulated by the experimenter
- The effect of this variable is a focus of the study
Dependent Variable
a factor that may change in response to an independent variable
- it is usually a behavior or a mental process
-this variable would be the effect of the drug
Case Study
A technique in which one person is studied in depth to reveal underlying behavioral principes
Random Sampling
If each member of a population has an equal chance of inclusion into a sample (unbiased). If the survey sample is biased, its results are not valid
Naturalistic Observation
Watch subjects in their natural environments
- Do not manipulate the environment
-Ex. Observing and recording the behavior of animals in the wild
Correlation
Expresses a relationship between 2 variables
- when 1 trait or behavior accompanies another we say the 2 correlate
-Ex. Smoking and lung cancer
-this does not necessarily mean causation
Positive correlation
Variables go in the same direction
Negative Correlation
Variables go in opposite directions
Correlation and causation
Double Blind Procedure
In evaluating drug therapies, patients and experimenters assistants should remain unaware of the real treatment and which patients had the placebo treatment
Statistics
tools that help us see and interpret what the unaided eye might miss.
Normal Curve
Representative samples
better that biased samples
- not exceptional and memorable cases one finds at the extremes
Less Variable observations
more reliable than more variable ones
- the average is more reliable when it comes from scores with low variability
More cases are better than fewer cases
average based on may cases and not just a few