/false）
Point Estimation
Estimating the population statistic based on a single sample statistic。
Pons
Part of the brain that plays a role in the regulation of states of arousal； including sleep and dreaming。
Population
The entire group to which research is hoping to generalize （e。g。； males； adults； U。S。 citizens）。
Population Mean
The true mean of the entire population often estimated using the sample mean。 Abbreviated with the lowercase Greek letter mu。 （m）
Population Standard Deviation
The true standard deviation of the population often estimated by using the sample standard deviation。 Often abbreviated with the lowercase Greek letter sigma。 （s）
Positive Correlation
A correlation where as one variable increases； the other also increases； or as one decreases so does the other。 Both variables move in the same direction。
Positive Reinforcement
Something positive provided after a response in order to increase the probability of that response occurring in the future。
Positive Skew
A curve or distribution of scores that has extreme scores above the mean that are atypical of the majority of scores
Power
The strength or the data to find a difference when there truly is a difference。 Power is abbreviated with the capital Greek letter beta （b）。
Predictive Validity
A measurements ability to predict scores on another measurement that is related or purports to measure the same or similar construct
Prejudice
Negative beliefs； attitudes； or feelings about a person's entire character based on only one characteristic。 This belief is often based on faulty information。
Preoperational Stage
Piaget's second stage of cognitive development in which a child develops objects permanency and language。
Pretest…Posttest Method
A method of determining the amount of change that occurred in a set of data by measuring the data prior to treatment and then after treatment and paring the two measurement outes。
Primacy Effect
The tendency to remember the first bit of information in a series due to increased rehearsal。
Primary Reinforcer
A reinforcer that meets our basic needs such as food； water； sleep； or love。
Proactive Interference
Interference in memory due to prior learning。
Probability of Error
The likelihood that error caused the results of data analysis。 If the probability of error is greater than the predetermined acceptable level of error then the results are said to be 'not significant。'
Probability Sample
Also called representative samples； a probability sample consists of characteristics that are close to the population that they represent。
Projection
In Psychoanalytic Theory； the defense mechanism whereby we transfer or project our feelings about one person onto another。
Projective Techniques
A generic term for the psychological procedures used to measure personality which rely on ambiguous stimuli。
Psychiatrist
A medical doctor with training in mental illness。
Psychoanalysis
Developed by Sigmund Freud； this type of therapy is known for long term treatment； typically several times per week； where the unresolved issues from the individual's childhood are analyzed and resolved。 These issues are considered to be primarily unconscious in nature and are kept from consciousness through a plex defense system。
Psychoanalytic Theory
Theory developed by Freud consisting of the structural model of personality； topographical model of personality； defense mechanisms； drives； and the psychosexual stages of development。 The primary driving force behind the theory is the id； ego and superego and the division of consciousness into the conscious mind； the pre/subconscious； and the unconscious。
Psychodynamic Therapy
A modern adaptation of psychoanalytic therapy which has made sometimes minor and sometimes major changes to Freud's original theories。
Psychotherapy
The treatment of mental illness or related issues based on psychological theory。
Psychology
The study of emotion； cognition； and behavior； and their interaction。
Psychosis
Break from reality； usually identified by hallucinations； delusions； and/or disorientation。
Psychotropic Medication
Prescription medication used primarily to treat mental illness。
Punishment
The adding of a negative stimulus in order to decrease a response （e。g。； spanking a child to decrease negative behavior）。
Q
Quasi…Experimental Research
Any research study that uses specific experimental methods but does not randomize subjects
R
R
Symbol used for the Pearson…product moment correlation （correlation coefficient）
Random Assignment
Assigning subjects to experimental groups based on chance。
Random Sample
A group of subjects representing the population who are selected through chance。
Range
the difference between the highest and lowest score in a distribution （often 1 is added to the result when puting statistics to allow for the 0。5 on either end lost due to rounding）。
Rank…Ordered Array
A table consisting of data in order of highest to lowest or lowest to highest where each data is given a numbered rank depicting it's difference from the highest or lowest score
Ratio Scale
Any scale of measurement possessing magnitude； equal intervals； and an absolute zero
Rational Emotive Therapy
A Cognitive Therapy based on Albert Ellis' theory that cognitions control our emotions and behaviors； therefore； changing the way we think about things will affect the way we feel and the way we behave。
Rationalization
A defense mechanism where one believes or states an acceptable explanation for a behavior as opposed to the real explanation。
Raw Data
The initial data gathered that has not yet been graphed； organized； or analyzed。
Reaction Formation
A defense mechanism where unacceptable impulses are converted to their opposite。
Reality Principle
According the Freud； the attempt by the ego to satisfy both the id and the superego while still considering the reality of the situation。
Recency Effect
The tendency to remember the last bit of information due to the shorter time available for forgetting。
Reconstruction
Tendency to fill in the gaps in our memory and often believe these represent true memories。
Referent Power
Power given to an individual due to respect and/or desire to be similar to that individual。
Reflection
A therapeutic technique in humanistic therapy where the feelings and thoughts of the client are reflected or reworded back to the client to assist in understanding them。
Regression Analysis
Used with a correlation to determine a regression equation that predicts or estimates a persons score on one variable if the other is known。
Rehearsal
Repeating information in order to improve our recall of this information。
Reinforcer
Anything that follows a behavior that increases the chances of that behavior occurring again。
Regression
A defense mechanism where one reverts to an earlier stage of development。
Reliability
A statistical measure of a tests consistency； or ability to result in similar scores if given repeatedly。
Reliability Coefficient
The correlation coefficient is called the reliability coefficient when a correlation is used to determine or estimate reliability。
Replication
The strength of a research study is only as good as its ability to be replicated。 In other words； if a study has significant results but can not be done again； it is difficult to assess whether it was a good study or a result of error。
Representative Sample
A sample or subgroup of the population that possesses the same characteristics of the population
Representativeness Heuristic
A rule of thumb where similarity to a prototype or similar situation dictates a decision。
Repression
In Psychoanalytic Theory； the defense mechanism whereby our thoughts are pulled out of our consciousness and into our unconscious。
Resistance
In psychoanalysis； the client's refusal to participate in a therapeutic intervention due to underlying issues unrelated to the intervention。
Response Prevention
A therapeutic technique where stimuli is presented to the client but the client is not permitted to exercise his or her typical re