Intro to Psych + Stats Flashcards
Define psychology.
The study of the mind and its processes.
Distiguish between psychologist and psychiatrist.
Psychologists follow a scientific approach; they provide treatment strategies and can diagnose disorders. Psychiatrists can do the same things, but they have a medical approach and can prescribe medication.
What is a social worker?
They offer support to immediate problems, help people process emotions and assist in their everyday lives.
Why is psychology a science?
It uses a scientific approach. (posing a question, conducting research, drawing conclusions based on
data)
Describe the scientific method.
A standardised way of making observations, gathering data, testing hypotheses and interpreting results to
establish theories in order to describe and measure human behaviour.
Distinguish between extraneous variables and confounding variables.
Extraneous variables have a chance of affecting the DV despite not being the IV. A confounding variable is when it actually happens; it does affect the DV.
What is the null hypothesis?
When it is predicted the IV will have no effect on the DV. It is assumed to be correct unless significantly proved otherwise.
What is the alternate hypothesis?
When it is predicted the IV will effect the DV.
Distinguish between populations and samples.
A population is a larger group of participants. A sample is a smaller group of selected participants.
Define convenience sampling.
When researchers use people easily accessible to them. Subject to bias.
Distinguish between random and stratified sampling.
Random is where every person in a population has an even chance of being selected. Stratified is where population is divided into sub-populations, and samples are drawn from each one.
What is the repeated measures experimental design?
Each participant is part of both the experimental and control group. Tested on two (or more) occasions
What is the matched participants experimental design?
Different participants in the experimental and control groups. Each group contains subjects matched on a particular variable
What is the independent groups experimental design?
Different participants in the experimental and control groups
Describe the placebo effect.
Participants’ behaviour is influenced by their expectations/beliefs. The single-blind procedure and eliminate this.
What is the experimenter effect?
Experiment being unintentionally (or intentionally) influenced by the experimenter. The double-blind procedure can eliminate this.
What is the correlational design?
Correlational research designs are non-experimental. there is no independent variable to manipulate. They measure two variables for statistical relationship
Distinguish between subjective and objective data.
Subjective refers to opinions with no external criteria. Objective refers to external criteria involvement.
Scales of measurement?
Nominal data: qualitative data that has no ranking or ordering of the values
implied.
Ordinal data: data that has a definite sequence but the gap between one level
and the next is not constant.
Interval data: data is measured on a scale with
regular intervals, but zero does not mean that the
property doesn’t exist.
Ratio data: measurements that represent quantities
with regular intervals and an absolute zero point of
origin.
Distinguish between parametric and non-parametric data.
Parametric data is when the data is distributed normally, interval and ratio data, variences are similar and sample sizes do affect it. Non-parametric is not normally distributed, nominal and ordinal data and has small sample sizes.
Distinguish between reliability and validity.
Reliablilty refers to the consistancy and stability of the measuring instrument. Validity refers to if the instrument is measuring what it needs to measure.
What are skews?
A positive skew is when the peak of the curve happens sooner. A negative skew is when the curve happens later. (refer to slide 77 of psychology tool box).
What are p-values?
the inferential tests will give a probability that the difference is caused by chance. If p= .03, then there are 3 chances in 100 (3%) that the difference is caused by chance. tells you the probability of observing the measured results of an experiment to determine if no effect is present.
What are t-tests?
Tests whether two variables are similar or not.
Mann-Whitney U test?
Tests if two variables are equal or not.
Types of error?
A type I error (a false positive) has occurred if the null hypothesis is incorrectly rejected.
A type II error (a false negative) has occurred if the null hypothesis is incorrectly kept.
What is the r-value?
represents the strength
and direction of the relationship between two variables.
Distinguish between Pearson’s correlation and Spearman correlation.
Pearson product moment correlation measures the linear relationship between two continuous variables: a change in one
variable is associated with a proportional change in the other variable.
Spearman correlation measures the
relationship between two ordinal variables and looks
at how they change together (not at a constant rate).
