Research Methods 2 Definitions

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Created by Just_Yasmin over 8 years ago


Research Methods 2 Flashcards on Research Methods 2 Definitions, created by Just_Yasmin on 05/02/2013.

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Question Answer
Effect Size Difference between two means in terms of standard deviations
Placebo Group experience exactly the same conditions as the experimental group expect for the level of the independent variable is thought to affect the dependent variable.
Non-Parametric Test significance test that does not make estimations of parameters of and underlying distribution.
Independent Variable one group of participants is subject to the experimental condition while an entirely different group of people participates in the control condition. These two conditions are the levels of the independent variable that was manipulated by the experiment.
Deduction Logical argument using rules to derive a conclusion from premises
Continious Scale there is no limit to the sub divisions of points that are possible and meaningful, though there will be limits in practice, depending on the type of measuring instrument used
Data Set group of data points or values which can be summarized or analyzed
Snowball Sample a technique often employed in qualitative research where the information is required from key people in an organization or from those whose have personal or professional experience with the research issue.
Central Tendency formal term for any measure of the typical or middle value in a group.
Pre-test Measure of participants before an experiment in order to balance or compare groups, or to asses changes by comparison with scores after the experiment.
Hypothesis testing research that analyses data for a predicted effect
Order effects effects from the order in which people participate in conditions.
Dispersion technical and general term fro any measure of the spread of scores in a sample of the population data.
Related design a score in one condition is discretely paired with a score in the other condition
Categorical Variable each value id a discrete and qualitatively separate categories
Measured Variable We can use a number to indicate where along a scale a person lies on this variable
Unrelated design the 'independent samples' or 'between groups'. Each score in one group or condition cannot in anyway relate to any specific score in the other group or condition.
Range the distance between the top and bottom values of a set
Reification the tendency to treat abstract concept as if it had independent existence.
Factors another name for independent variables
Construct Validity the extent to which our measure actually coincides with the construct
Inter-quartile range distance between the first and third quartile in the distribution
Operational definition definition of phenomenon in terms of the precise procedures taken to measure it.
Hypothetical construct phenomenon or construct assumed to exist and used to explain observed effects, but as yet unconfirmed; stays as an explanation of effects while evidence supports it.
Asymmetrical order effect an order effect that has greater strength in one particular order and where, therefore, counterbalancing would be ineffective
Semi inter quartile range half the distance between first and third quartile in a distribution
Reliability The extent to which findings or measures can be repeated with similar results. Consistency of measures
Baseline Comparison Measure of what would occur if no experimental level of the independent a
Deviation value/ score the amount by which a particular value deviates from the mean
Validity the extent to which instruments measure what they intended to measure. Also the extent to which a research effect can be trusted as real or as not 'contaminated' or confounded.
Population all the existing members of a group
Sample A group selected form the population for an investigation
Simple Random Sample every case in the target population has an equal chance of selection and so does every possible combination of cases
Systematic Random Sample select every nth case form the population where n is an number. before selection is started every case must have an equal chance of being in the sample
Sampling Frame the population from which we will sample from
Factorial Design experiment in which more than one independent variable is manipulated
Mean Deviation measure of dispersion- mean of all absolute deviations
Non-equivalent Groups A possible confounding variable where two or more groups in a independent samples design experiment differ on a skill or characteristic relevant to the dependent variable
Standard Score number of standard deviations a particular score us from it's sample mean.
Sampling Distribution Theoretical distribution that would be obtained by taking the same statistic from many same size samples
Stratified Sample A sample is selected so that specified groups will appear in numbers proportional to their size in the target population; within each sub-group cases are selected randomly.
Cluster Sampling groups in the population selected at random from among other similar groups and assumed to be representative of a population.
Sampling Error difference between a sample statistic and the true population statistic, usually to assumed to be random in origin
Degrees of freedom common term in statistical analysis having to do with the number of individual data points that are free to vary given that overall summary values are known.
Standard error the distribution has a standard deviation
Quota Sampling Consists of obtaining people from categories, in proportion to their occurrence in the general population but the selection from each category is entirely determined by the researcher
Self selecting Sample researcher use participants that are readily available
Variation ratio proportion of non-modal values to all values
Central Limit Theorem Used in theoretical estimations of standard error of sampling distribution from standard deviation of a sample.
Opportunity/Convenience Sample a sample selected because they are easily available for testing
Confidence Intervals limits to the likely interval within which a population mean lies based on an estimate from a sample mean and standard error
Haphazard Sample A sample selected from the population with no conscious bias ( but not likely to be truly random)
Sample statistics measures of a sample. they are frequently taken as an estimate of the same measures of a population
Purposive Sample The selection choice is made by the researchers on the basis of those who are more representative for the research issue or who are likely to have expertise in the matter
Line charts chart joining continuous data points in a single line
Skewed Distribution non-normal distributions that have a lot more scores on one side of the mode than the other
Natural Experiments. events beyond the researcher's direct control but where an Iv and DV can be identified.
Participant Variable Variations between persons acting as participants & which are relevant to the study
time-series line chart showing measures of variable at progressive time intervals.
Sampling Bias The weighting of a sample with an over-representation of one particular category of people
Ceiling Effect occurs where a measure produces most values near the top end of a scale
Floor Effect phenomenon where measures produce very many low scores
Group difference studies a post facto study that compares the measurements of an existing variable in two contrasting conditions.
Kurtosis the overall shape of a distribution in terms of height and width compared with normal distribution
Frequency Polygon histogram showing only the peaks of class intervals
Platykurtic non-normal distribution that is widely spaced out and low in the centre
Leptokurtic Non-normal distribution that is closely bunched in the center and tall
Significance test test performed in order to decide whether the null hypothesis should be retained or rejcted
Explanatory data analysis close examination of data by a variety of means before submitting them to significance testing
Null Hypothesis Assumption of no effect in the population from which the samples are drawn
Alternative Hypothesis assumption that an effect exists
Mundane realism feature of design where experiment resembles everyday but is not necessarily engaging
Participant Variable person variables differing in proportion across different experimental groups and possibly confounding results
standardized procedure Testing or measuring behavior with exactly the same formalized routine for all participants
Experimenter realism effect of attention-grabbing interesting experiment in compensating for artificiality or demand characteristics
Cumulative frequency distribution that shows the number of cases that have occurred up to and including the current category
Significance Level levels of probability at which it is agreed to reject the null hypothesis. if the probability if obtained results under the null hypothesis is less than the set level then the null hypothesis is rejected
Error Variance Variance among scores caused by the operation of randomly acting variables.
Box plots based on ordinal measurements of the set of data. The give us a graphical representation of the inter-quartile range
Experimental Validity The truth of conclucions drawn about an experiment.
Deception Leading participants to believe tat something other than the true independent variable is involved or withholding information such that the reality of the investigative situation is masked or distorted
Raw data the unprocessed data gathered directly from participants before they are organized or treated statistically.
Frequency Distribution distribution showing how often certain values occurred in categories
Debriefing informing participants about the full nature and rationale of the study they've experienced and attempting to reverse any negative influences
Threats to Validity any influence on research variables that might provide an alternative explanation of our effect or that might limit generality of what we appear to have found.
Stress and Discomfort psychological investigators should guarantee the safety of their participants and that everything possible should be done to protect them from harm of discomfort
Percentile point of on a measured scale that marks off a certain percentage of cases in a data set
Decile Point on a measured scale that marks off each 10% of the data set of the population
The Right to Withdraw in all research that involved individual participation the investigator is obliged to - 1. give participants at to likely levels of discomfort, 2. remind them of their right to withdraw & 3. terminate the experiment if discomfort levels are higher than anticipated
Normal Distribution continuous distribution, bell shaped, symmetrical about its mid-point.
Categorical weekend variable where cases are merely placed into independent, separate categories
Informed Consent agreement to participate in research in the full knowledge of the research context and participant rights
Construct Validity whether our measures of a construct are really measuring it, and also the extent to which the construct itself is supported by psychological evidence
Measured Variable variable were cases measured on it are placed on some sort of scale that has a direction
Participant expectancy the expectation on the part of the participants that their behavior should alter in an experimental situation
Demand Characteristics cues in a study which help participants work out what is expected
Social desirability the tendency of research participants to want to look good and provide socially acceptable answers.
Anonymity keeping participants or clients identity away from publication or any inadvertent disclosure
Evaluation apprehension participants concern about being tested, which may affect results.
Reactive studies in which the participant is expected to react to being studied
Confidentiality keeping data from participants or clients away from publication
Single Blind participants do not know what condition they are in
Nominal Level level of measurement at which numbers are the only labels for the categories
Double blind an experimental procedure whether neither the participants or the experimenter knows what condition the participant is in
Expectancy control design half of the participants receive the experimental treatment and half do not as in the standard between groups design.
Intervention research that makes alteration to peoples lives beyond the specific research setting in some cases because there is an intention to ameliorate specific human conditions
Independent Variable The thing that is manipulated
Dependent Variables The resulting behaviour that is measured
True Experiment Participants are randomly assigned to conditions
Quasi-experiments Participants are already on groups
Between Participants divide the set of participants into two group. Each group has a different condtion
Within Participants Each participant does the task twice. Once in each condition
Population Validity the extent which an effect can be generalized from the sample to the sample population from which they were selected and to other populations
Frequencies number of cases in specific categories. These numbers are being used to count, they do stand for quantities.
One-tailed Hypothesis X will be bigger/smaller than Y
Critical Value value that the results of our test statistic must reach in order for the null hypothesis to be rejected.
Two- tailed Hypothesis X will be different to Y
Type II Error The probability of retaining the null hypothesis when it is false
ordinal level level of measurement at which cases are arranged in rank position
Ecological Validity the extent to which findings generalize to other settings
Internal validity when we can conclude that the independent variable brought about the observed changes in the dependent variable
Effect Size the size of the effect being investigated as it exist in the population
Interval level level of measurement at which units on a scale represents an equal change in the variable measured
External Validity The degree to which we can generalise our results to other participants, other conditions, other times and other places
Confounding Variables A variable that systematically changes with the independent variable and dependent variable
Power The probability of not making a type II error if a real effect size occurs. The probability of selecting a case or sample above the level of Beta in the population defined by the alternative hypothesis id 1 - Beta
Meta-analysis Statistical analysis of results results of multiple equivalent studies of the same or very similar hypotheses in order to assess more thoroughly an effects validity
One tailed Test test referring to only one tail of the distribution under the null hypothesis. May be used i alternative hypothesis is directional
Hawthorne effect effect on human performance caused solely by the knowledge that one is being observed
Two Tailed hypothesis test referring to both tails of the probability distribution. Must be used if the alternative hypothesis is non-directional
Critical Case A special case may sometimes highlight things that can be related back to most non-special cases
Lab Experiment conducted in a highly controlled artificial environment. There is a problem of low external validity
Parametric test Relatively powerful significance test that makes estimations of population parameters. The data tested must usually therefore satisfy certain assumptions.
Field experiment conducted in naturally occurring environment for participants
Focus Groups & Panels Researchers may bring together a panel of either experts, those with a particular interest in a topic or in the case of focus groups, simply a selection of people who are fairly representative of the general population.
Distribution Dependent Test significance test making estimations of population parameters.
Placebo Inert innocuous version of treatment resulting in psychosomatic placebo effect.
Quasi-interval scales scale that appears to be interval but where equal intervals do not necessarily measure equal amounts of the construct.
Sampling Bias Systematic tendency towards over- or under- representation of some categories in a sample
Difference Mean mean of differences between pairs of scores.
Ratio interval type scale where proportions on the scale are meaningful because there is an absolute zero point
Pooled Variance combining of two sample variances is to average in order to estimate population variance
Positivism Methodological belief that the world's phenomena are reducible to observable facts and the mathematical relationships between them.
Control Groups groups used as a baseline measure against which the performance of the experimental group is assessed
Discrete Scale each point is entirely separate from the next
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