Range The difference between the highest and lowest values + Easy to calculate - Affected by extreme values Standard Deviation The average distribution that each piece of data is from the mean for the group + Takes each piece of data into account so very sensitive +...
Research Methods
Presentation of Quantitative Data
Bar charts Used to represent data which is divided into categories (discrete data) e.g. yes or no Line graphs Used to represent data in numerical form (continuous data) e.g. the age of a person Histograms Represent continuous data. Bars represent each score rather...
3 Types of Measurement:
Nominal level: category data e.g. yes/no Ordinal level: data that is a score or ranked on a scale e.g. 1st 2nd Interval data: standard unit of measurement e.g. seconds, KG Why are statistical tests important? Tell us the probability of the results being due to chance...
Type I and Type II Errors
The significance level is 5% or 0.05 to provide a good balance between being too strict or lenient about whether the results of research are significant OTHER THAN WHEN GIVEN OTHERWISE. However, 0.05 gives best chance of avoiding these 2 errors Type I – false...
Assessing Which Statistical Test to Choose:
1.) What kind of data do I have? Nominal level (non-parametric): category data e.g. yes/no Ordinal level(non-parametric): data that is a score or ranked e.g. 1st 2nd Interval data (parametric)– standard unit of measurement e.g. seconds, KG Criteria of parametric data...
Structure of long answer Q’s: Write an informed consent form
Dear Participant, Thank you for agreeing to take part in a study on the effect (AIM) You will be asked to do this and that (PROCEDURE) There will be medical support provided throughout if you need it and you can withdraw at any time All data will be treated with...
Write a Debrief
start with ‘dear participant’ thank you for taking part in the study disclose the full aim of the study refer to previous research if given in Q remind pt of right to withdraw data reassure pts of confidentiality (no personal data published) state researchers contact...
Write Standardised Instructions
explain why or how to conduct a pilot study use a methods section (inc subheadings: design, procedure, pts, materials) write a results section (inc table of results, graph, selection of statistical test) evaluate the limitations of a study and make suggestions for...
Ethics
The rights and wrong about how we conduct research, which is governed by ethical guidelines set by BPS (British Psychological Society) Fully informed consent Participants should have knowledge of aims + procedures of research so they can decide if they want to be...
Reliability
A measure of consistency and the ability to repeat experiment and get similar results on another occasion Internal reliability: Whether a measure is consistent within itself when tested – eg a questionnaire generating similar results with all participants. Tested...
Validity
How true a study or theory is an explanation of behaviour Internal validity: Whether the research was designed ‘well’. Research with high internal validity, must be designed very carefully. Can be lowered through the interference of extraneous variables. Face...
Features of Science
Objectivity When the researcher is not being affected by their own expectations, keeping a distance from it. How to ensure objectivity: Data should be collected systematically under controlled conditions e.g. lab Research method should be fully standardised so less...
Features of a Scientific Report
TITLE: normally phrased as a question. Refers to the aim ABSTRACT: brief summary of aims and hypotheses, previous research, results, methods and conclusion. 150-200 words. Written at the end but on front page INTRODUCTION: includes past research (theory and studies)...
Data Handling and Analysis
Quantitative data Data in numerical form which can be put into categories, or in rank order, or interval data, and is used to make graphs and tables of raw data - e.g. correlations, experiments, closed questions easily summarised into graphs or statistics = identify...
Measures of Central Tendency:
Mode Most common or most frequent value (used with nominal data) + Easy to calculate + Can be used with nominal data - Doesn’t tell us anything except which thing happens most - Multimodel distributions can be uninformative Median Middle number when data is in rank...
Research Methods
Aim: An intention of investigation Hypothesis: A predictive, operationalised statements of expected outcome Null hypothesis: Predicts IV has no effect on DV Alternative hypothesis: Predicts that there will be a significant effect on DV because of the IV Directional...
Types of Variables
Dependent variable (DV) = measured Independent variable (IV) = manipulated Controlled variable (CV) = kept constant Extraneous variable (EV) = anything other than the IV that could affect the DV – individual differences Confounding variable = EVs have that already...
Experiments
Choice of experiment is dependent on: - How much control we have over IV - How much control we have over extraneous variables - Decision between reliability OR validity In an experiment: - One variable is kept constant - Another measured to see if it changes (IV)...
Experimental Design
- Allocating participants to conditions - Independent measures, repeated measures, matched pairs Repeated measures Participants take part in both conditions + Any difference between conditions likely to be due to IV not pts variables + Controls individual differences...
Independent Measures
Divided randomly into 2 groups + each does a different condition of IV + Each pts sees only ½ of study = harder for them to work out aim of study = reduces demand characteristics + Avoids practice & order effects = pts only does 1 condition = cannot be affected by...
Self-report Studies
Questionnaires Self-report method in which a series of answers is given in a written format, either by making a choice/ answer (closed question) or an extended answer (open question) + Collect large amount of data quickly from large sample (compared to techniques e.g....
Observation
Naturalistic observation Observation of behaviour in a natural setting, with no investigator interference + High in ecological validity + Used to generate ideas for experimental research / validate experimental findings - No manipulation of variables = cannot infer...
Types of Sampling Procedures
Event sampling= recording the number of times a certain behaviour occurs in a group Time sampling = recording behaviours in a given time frame e.g. recording every 30 seconds Correlational analysis Statistical analysis based on a relationship between co-variables...