QUANTITATIVE RESEARCH Intervention Research: - Experimental Research Non-Intervention Research: - Correlation Research - Survey Research
EXPERIMENTAL RESEARCH An experiment research is a research situation where at least one independent variable, called the experimental variable, is deliberately manipulated or varied by the researcher. The purpose of experimental research is to study cause and effect relationships.
VARIABLE Independent Variable experimental or treatment variable (it is the cause) Dependent Variable/Measured Variable is what is measured to assess the effects of the independent variable
INSTRUMENT tools researchers use to collect data for research studies (alternatively called “tests”) The types of instruments: 1. Cognitive Instruments 2.Affective Instruments 3.Projective Instruments
COGNITIVE INSTRUMENTS Measure an individual’s attainment in academic areas typically used to diagnose strengths and weaknesses. Types of cognitive instruments:
provide information about how well the test takers have learned what they have been taught in school
measure the intellect and abilities not normally taught and often are used to predict future performance
Affective instruments Measure characteristics of individuals along a number of dimensions and to assess feelings, values, and attitudes toward self, others, and a variety of other activities, institutions, and situations.
Types of affective instruments: attitude scales self-reports of an individual’s beliefs, perceptions, or feelings about self, others, and a variety of activities, institutions, and situations values tests measure the relative strength of an individual’s valuing of theoretical, economic, aesthetic, social, political, and religious values personality inventories an individual’s self-report measuring how behaviors characteristic of defined personality traits describe that individual
Projective instruments Measure a respondent’s feelings or thoughts to an ambiguous stimulus Primary type of projective test:
participants react to a stimulus such as a picture, inkblot or word onto which they project a description.
Two issues in using instruments 1.Validity: the degree to which the instrument measures what it purports to measure 2.Reliability: the degree to which the instrument consistently measures what it purports to measure
Types of validity 1. Content validity the degree to which an instrument measures an intended content area. 2.Criterion-related validity an individual takes two forms of an instrument which are then correlated to discriminate between those individuals who possess a certain characteristic from those who do not 3.Construct validity a series of studies validate that the instrument really measures what it purports to measure
Types of reliability... 1.Stability (“test-retest”): the degree to which two scores on the same instrument are consistent over time 2.Equivalence (“equivalent forms”): the degree to which identical instruments (except for the actual items included) yield identical scores 3.Internal consistency (“split-half” reliability with Spearman-Brown correction formula , Kuder-Richardson and Cronback’s Alpha reliabilities, scorer/rater reliability): the degree to which one instrument yields consistent results