
Bar Graph (129)
Graph, variables on the xaxis is measured on a nominal/ordinal scale; because the xvariable isn't continuous, the bars don't touch.

Class Interval (128)
Subset of a range of scores; in a grouped frequency distribution, the number of participants who fall into each class interval is shown.

Cluster Sampling (119)
Sampling procedure in which the researcher first samples groups/clusters of participants, then obtains participants from the selected clusters.

Convenience Sample (124)
A nonprobability sample of whatever participants are readily available.

Crosssectional survey design (110)
Design in which a group of respondents is studied once.

Demographic Research (114)
Descriptive research that studies basic life events in a population, ex. patterns of births, marriages, deaths, & migrations.

Descriptive Research (109)
Describes in an accurate & systematic fashion the behavior, thoughts, or feelings of a group of participants.

Economic Sample (116)
provides a reasonable degree of accuracy at a reasonable cost in terms of money, time, & effort.

Epidemiological Research (114)
Studies the occurrence of disease in different groups of people

Epsem Design (117)
Sampling procedure in which all cases in the population have an equal probability of being chosen for the sample; (epsem stands for equalprobability selection method)

Error of Estimation (116)
The degree to which data from a sample is expected to deviate from the population as a while, (also called margin of error)

Frequency (127)
The number of participants who obtained a particular score

Frequency Distribution (127)
A table that shows the number of participants who obtained each possible score on a measure

Frequency Polygon (129)
A form of line graph.

Graphical Method (127)
Presenting and summarizing data in pictorial form, (graphs & pictures)

Group Frequency Distribution (128)
A table showing the number of participants who obtained each of a range of scores

Histogram (128)
A form of bar graph in which the variable on the xaxis is on a continuous scale

Internet Survey (112)
A survey in which respondents access & respond to research materials on the web

Longitudinal Survey Design (112)
A study in which a single group of participants is studied over time

Margin of Error (116)
The degree to which data obtained from a sample are expected to deviate from the population as a whole; also called Error of Estimation

Mean (132)
The mathematical average of a set of scores

Measures of Central Tendency (132)
Descriptive statistics that convey information about the average in a distribution; ex. mean, median, mode

Measures of Variability (133)
Descriptive statistics that convey information about the variability of a set of data; ex. range, variance, S.D.

Median (133)
The score that falls at the 50th percentile, middle score

Mode (133)
The most frequent score in a distribution

Multistage Sampling (120)
Cluster sampling in which large clusters of participants are sampled, followed by smaller clusters from within the larger clusters, followed by still smaller clusters, until participants are sampled from the small clusters

Negatively Skewed Distribution (134)
A distribution in which there are more high scores than low scores

Nonprobability Sample (123)
A sample selected in a way that the likelihood of any member of the population being chosen cannot be determined

Nonresponse problem (121)
The failure of individuals who are selected for a sample to agree to participate or answer all questions; nonresponse is a problem when probability samples are used in descriptive statistics

Normal distribution (134)
A distribution of scores that rises to a rounded peak in the center with symmetrical tails descending to the left & right of the center

Numerical Method (127)
Presenting & summarizing data in numerical form, ex. means, percentages, etc.

Outlier (133)
an extreme score; typically scores that fall farther than + or  3 standard deviations from the mean

Positively Skewed Distribution (134)
A distribution in which there are more low scores than high scores

Probability sample (117)
A sample selected in a way that the likelihood of any individual in the population being selected can be specified

Proportionate sampling method (119)
A variation of stratified random sampling in which cases are selected from each stratum in proportion to their prevalence in the population

Purposive Sample (124)
A sample selected on the basis of the researcher's judgement regarding the "best" participants to select for research purposes

Quota Sample (124)
A sample selected to include specified proportions of certain kinds of participants

Range (133)
A measure of variability that is equal to the difference between the largest & smallest scores in a set of data

Raw Data (127)
The original data collected on a sample of participants before they are analyzed

Relative Frequency (128)
The proportion of participants who obtained a particular score

Representative Sample (116)
A sample from which one can draw accurate, unbiased estimates of the characteristics of a larger population

Sample (115)
A subset of a population; group selected to participate in a study

Sampling (115)
The process by which a sample is chosen from a population to participate in a study

Sampling Error (116)
The difference between scores obtained on a sample & the scores that would have been obtained if the entire population had been studied

Sampling Frame (117)
A list of the member of a population

Simple Frequency Distribution (127)
A table that indicates the number of participants who obtained each score

Simple Random Sample (117)
A sample selected in a way that every possible sample of the desired size had the same chance of being selected

Standard Deviation (133)
A measure of variability that is equal to the square root of the variance

Stratified Random Sampling (119)
A sampling procedure in which the population is divided into strata, then participants are sampled randomly from each stratum

Stratum (119)
A subset of a population that shares a certain characteristics; ex. a population could be divided into the strata of men & women

Successive Independent Samples Survey Design (110)
A design in which different samples of participants are studied at different points in time

Table of Random Numbers (118)
A table of numbers that occur in a random order used to select random samples or to assign participants in a random fashion

Variance (133)
A numerical index of the variability in a set of data

Zscore (137)
A statistic that expresses how much a particular participant's score varies from the mean in terms of standard deviations; also called standard score

