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Quantitative Research. Descriptive Research. Also called “Survey Research” Describes the way things exist Data collected Test hypothesis Or to classify opinions on issues/topics. Descriptive Research. Most common research Surveys conducted
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Descriptive Research • Also called “Survey Research” • Describes the way things exist • Data collected • Test hypothesis • Or to classify opinions on issues/topics
Descriptive Research • Most common research • Surveys conducted • Many fields covered: education, politics, social and economic • More complicated than one may think
Descriptive Research • Classified by data collection method • Self report (survey) • Observation (participants watched)
Descriptive Research • Survey types • Cross-sectional • Data collected at one point in time • Longitudinal • More than once to measure growth or change
Descriptive Research • Cross-sectional survey • Single point in time may not provide perspective needed • Example: census survey
Descriptive Research • Longitudinal survey • Collected multiple times from different samples and groups • Four types of longitudinal surveys • Trend, cohort, panel, and follow-up
Descriptive Research • Trend survey • How are attitudes changing or consistent among changing sample groups • Cohort survey • Different samples from the same group are surveyed over several time periods
Descriptive Research • Panel survey • Same group and sample are surveyed over time • Follow-up survey • Similar to panel study, but performed after the panel study complete (examines later changes) • Usually to evaluate a college instructional program
Descriptive Research • Conducting self-report research • Standardized, quantifiable information collected • Questionnaire is written • Interview is an in-person Q&A session between researcher and participant
Descriptive Research • Conducting a Questionnaire study • Most efficient • Larger data sample collected • Mailing is preferred
Descriptive Research • Topic under investigation must be significant for subjects to respond • Problem defined in specific objectives • Each item on survey must directly relate to objectives
Descriptive Research • Participants • Chosen from appropriate sample • Possess needed information and are willing to share it
Descriptive Research • Questionnaire • Brief, easily answered • Structured (close-ended) response choices • Facilitate easy responses • Data analysis objective and efficient
Descriptive Research • Questionnaire • Structured items are scaled (ex. Likert) • Unstructured items – complete freedom of response • Provide more depth • Difficult to measure
Descriptive Research • Questionnaire • Item construction • Each questions focuses on one concept • Concisely worded • Concepts or terms with multiple connotations are defined • Avoid leading questions
Descriptive Research • Questionnaire • Pretesting • Smaller, but similar group • Data will indicate any measurement difficulties and suggest improvement • Make sure it measures what it is designed to measure
Descriptive Research • Questionnaire • Analyzing results • Indicate % of respondents who selected each alternative answer for each item • When possible, also analyze summed item clusters • Groups of items focusing on same issue • Variable relationships can be investigated (female vs. male responses) for each cluster
Descriptive Research • Interview Study • More in-depth data collected if successful • More expensive and time-consuming • Smaller sample population used
Descriptive Research • Interview Study • Written guide for administrator • Includes any prompts or additionally allowed probing • Standardized, comparable data requires all interviews must be conducted in same manner
Descriptive Research • Interview Study • Uses same guidelines from questionnaire construct • Responses recorded manually or by recording device (participants must consent)
Correlational Research • Data collected to determine: • Is there a relationship between two variables? • To what degree is the relationship? • Degree of relationship is expressed as a correlation coefficient
Correlational Research • Correlation coefficient • Measured on a scale from +1.00 to -1.00 • If variables highly related, correlation coefficient near +1.00 or -1.00 will be obtained • If not related, a correlation coefficient near .00 will be obtained
Correlational Research • Correlation coefficient • Interpretation • Lower than (+ or - ) .35 – low or none • Between (+ or -) .35 and .65 – moderate • Higher than (+ or -) .65 – High relationship
Correlational Research • Correlation coefficient • Interpretation • A high relationship between two variables doesn’t necessarily mean one causes the other • There may be a third variable that causes them both
Causal-Comparative Research • Determines cause for differences in behavior or status of groups of individuals • The effect and the cause have already happened • Mostly studied in retrospect • Example: Pre-school and social adjustment in 1st grade
Causal-Comparative Research • Prospective approach slightly different • Start with a cause and investigate its effect on a variable • Example: social promotion in 7th grade
Causal-Comparative Research • The independent variable • A behavior or characteristic believed to influence some other behavior or characteristic (pre-school attendance) • The dependent variable • The change or difference in a behavior or characteristic due to an independent variable (social adjustment in 1st grade)
Causal-Comparative Research • The independent variable • Not manipulated in Causal-Comparative Research • This is the major difference between this and Experimental Research • In Causal-Comparative Research, groups are already formed and divided by the independent variable
Causal-Comparative Research • The independent variable • Basic Causal-Comparative Research design finds two groups differing on some independent variable, and comparing them on a dependent variable
Causal-Comparative Research • Groups may differ in characteristics • Select samples that represent their respective populations
Causal-Comparative Research • Data analysis and interpretation • Descriptive statistics • The mean – average performance of group on a measure of some variable • Standard deviation – measure the “spread” of scores around the mean (are they relatively close together or widely spread)
Causal-Comparative Research • Data analysis and interpretation • Inferential statistics • t test – indicates if there is a significant difference between the means of two groups • Analysis of variance – significant differences between means of three or more groups • Chi square – does an event occur more frequently in one group than another?
Causal-Comparative Research • Data analysis and interpretation • Use caution • Alleged cause-effect relationship may be the effect or a third factor may cause the independent and dependent variables • Correct order of causality – which variable caused which? The one that occurred first
Experimental Research • Researcher manipulates at least one independent variable • Controls other variables • Observes effect on one more dependent variables
Experimental Research • Independent variable • a.k.a. experimental variable, cause, or treatment • Believed to make a difference in some performance
Experimental Research • Dependent variable • a.k.a. criterion variable, effect, or posttest • Outcome of the study • Measure of change or difference resulting from independent variable manipulation
Experimental Research • Experimental studies yield the soundest evidence when conducted well • Prove or disprove hypothetical cause and effect relationships
Experimental Research • The process • Select/define problem • Guided by one hypothesis • Researcher in control • Experimental group receives unique treatment • Control group receives different treatment
Experimental Research • The process • All other variables are equal to both groups that may effect dependent variable • After exposed to treatment for some time, researcher applies dependent variable and measures differences
Experimental Research • Manipulation and control • Sets experimental apart from all others • Three forms of independent variable manipulation • Presence versus absence (A vs. no A) • Presence varying degrees (much A vs. little A) • Presence of one kind/another kind (A vs. B)
Experimental Research • Manipulation and control • Control: efforts to remove outside influences of any variable (other than independent variable) that may affect dependent variable
Experimental Research • Two controlled variables • Participant variables • Members of different groups may have characteristic differences • Environmental variables • Any change in experimental setting that may influence performance differences
Single-Subject Experimental Research • Studies individual behavior change • Result of some treatment form • Repeated formula • Receives no treatment or intervention • Tested • Receives treatment / intervention • Tested