introdction to psychology research methodology n.
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  2. Topics: • Research in Psychology • Quantitative Research: The Experiment • Quantitative Research: Correlational Studies • Qualitative Research • Qualitative Research Methods • Ethics in Psychological Research

  3. What is Psychology? • Psychology is a broad and diverse area of endeavor, one that has evolved from relatively humble beginnings in the nineteenth century into a science that is now concerned with a great many different aspects of our lives. • Modern psychology is comprised of many specialty areas that are interwoven PAVLOV FREUD SPERRY SKINNER

  4. Psychology Should: • Be supported by empirical evidence and be based on this evidence. • Be falsifiable, it should be possible for the theory or study to be proven. • Be a history of attempts to replicate the theory or study.

  5. How it Began: • Under the influence of Charles Darwin and his theories of evolution, people began to become interesting in studying animals and animal intelligence.

  6. Clever Hans • Clever Hans was a horse that was owned by Wilhelm von Olsten. Olsten claimed he has taught the horse to solve arithmetic problems. A special commission was assigned in Germany to determine if it was a fraud and they concluded that it was not. Clever Hans would tap his hoof in response to the number that was the answer.

  7. Oskar Pfungst • Oskar Pfungst carried out his own independent investigation and determined that Clever Hans really did not know how to solve the equations but was taking cues from Olsten and even the audience. • Pfungst successfully tested several hypothesis…

  8. Alternate Hypotheses: • Maybe the spectators were given clues to the horse. In the absence of spectators the horse was still giving the correct answers. • Maybe Olsten was giving clues to the horse. Another questioner was used but the horse still got the answers correct. • What if somehow the questioner is giving the answer away? So blinders were used. When the blinders were used Hans could not answer correctly so it was something with the questioner. • In future trials the questioner was not given the answer. When they did not know the answer, Hans could not answer correctly.

  9. Clever Hans was Not So Clever or was he? • As it turns out after further trials, it was determined that the questioner would become more tense and change their facial expressions when approaching the correct answer. • They concluded that the horse could sense these changes. Hans was clever but he was not able to solve mathematical equations.

  10. Artifacts • As a result of the Clever Hans research it was discovered that if an experiment is not carefully controlled it could produce artifacts. • Artifacts are results that are associated with the effect of unforeseen factors.

  11. What is Behavior? • The empirical approach to research relies on observation as a means of data collection. • Behavior is everything that can be registered by an independent observer. Over actions, gestures, facial expressions, verbal responses…

  12. Quantitative versus Qualitative • Quantitative research involves variables which is anything that can take on different values. • Qualitative research involves an in-depth study of a particular phenomenon. Qualitative studies cannot also measure what is being studied and may have more of a degree of subjectivity.

  13. What is a variable? • A variable is something that can take on different values. It is any characteristic that can be objectively registered and quantified. • There are independent and dependent variables in an experiment.

  14. In psychology there are lot of “internal” characteristics that cannot be directly observed. • There is a important distinction between constructs and operationalizations. • A construct is any theoretically defined variable such as violence, attraction, memory, aggression, love, anxiety. Constructs cannot be directly observed they are based on a theory. • To operationalize means to express the construct in terms of an observable behavior. For example to look at aggression you may look at the number of swear words a person uses in a period of time. • How would you operationalize some of the other examples listed above? Operationalization

  15. Three Types of Quantitative Research • Experimental Studies • Correlational Studies • Descriptive Studies

  16. Experimental Studies • In the simplest form an experiment will contain one independent variable (IV) and one dependent variable (DV). • The independent variable is manipulated by the researcher. • The experiment is the only method that allows cause and effect inferences.

  17. Correlational Studies • Correlational studies are different in that the researcher does not manipulate a variable.. • Variables are measured and the relationship is quantified.

  18. Descriptive Studies • The relationship between variables is not studied. • Each variable is approached separately. • An example would be a public opinion survey. • The researcher is interested in the distribution of answers. • They are often used in sociology.

  19. Sampling, Credibility, Generalizability and Bias • Sampling, credibility, generalizability, and bias are some of the characteristics used to describe a research study and determine its quality. • These characteristics are universal for social science but can be approached differently.

  20. Sampling • A sample is the group of individuals who are taking part in the study. • Sampling is the process of finding and recruiting individuals to participate. • The sample should suit your aim. • Example: If you are trying to determine how teenagers would react to a situation, you would need to have the sample consist of teenagers.

  21. Credibility and Bias • Credibility is the degree to which the results can be trusted to reflect reality. • To be credible, results must not reflect bias. • There are many circumstances that can create bias. For example the subjects may have determined the aimor the subjects are trying to please the researcher.

  22. Generalizability • This refers to what extent the results can be applied beyond the sample. • Can the results be maintained cross culturally? • The sample is the group of people to be studied and the target population is the group that the results may be applied to.

  23. Confounding Variables • A confounding variable is an “extra” variable that you didn’t account for. • They can ruin an experiment and give you useless results. • They can suggest there is correlation when in fact there isn’t. • They can even introduce bias. • That’s why it’s important to know what one is, and how to avoid getting them into your experiment in the first place. Example: You manipulate X to see a change in Y but inadvertently change Z. Z is what is causing the effect in Y rather than X.

  24. SAMPLING TECHNIQUES Random: A random sample is one chosen by a method involving an unpredictable component. Stratified Sampling: is a probability sampling technique wherein the researcher divides the entire population into different subgroups or strata, then randomly selects the final subjects proportionally from the different strata. Convenience Sampling: This is when you recruit participants that are easily available. Self-Selected Sampling: this is when people choose to participate in the study by volunteering or signing up.

  25. Experimental Design How are the participants allocated to the different conditions? Independent Measures: Different participants are used in each condition of the independent variable. This means that each condition of the experiment includes a different group of participants. This should be done by random allocation. Matched Pair Design: this is similar to independent design but the researchers use matching to form the groups. Repeated Measures: The same participants take part in each condition of the independent variable. This means that each condition of the experiment includes the same group of participants. In repeated measures they could be subject to order effects. Counterbalancing is used to overcome order effects. You must justify your choice. Independent Measures Repeated Measures

  26. Validity Construct Validity: refers to the degree to which inferences can legitimately be made from the operationalizations in your study to the theoretical constructs on which those operationalizations were based. Internal Validity: this refers to the methodological validity of the experiment. External Validity: this refers to generalizability of the findings in the experiment. Population Validity: can the findings be generalized from the subjects to the target population. Ecological Validity: can the findings be generalized to other situations or settings.

  27. BIAS-Threats to Internal Validity • Bias in research usually comes from confounding factors that may influence the cause and effect relationship between the IV and DV. • On the following page are common threats to internal validity in experiments.

  28. Selection: There is some sort of variable before the experiment begins that makes the group selected unequal. History: Outside events might affect a participant in an experiment. This is more likely to occur in a longitudinal or lengthy experiment. Maturation: Participants may go through natural development such as fatigue or growth. Testing Effect: The first measurement of the DV might affect. Instrumentation: the instrument used to measure the DV changes slightly.

  29. Regression to the Mean: when the initial score on the DV is either really high or low. Experimental Mortality: some participants drop out during an experiment. Demand Characteristics: this is when the participants understand the purpose of the experiments and change their behavior. Experimenter Bias: the researcher unintentionally exerts influence on the study.

  30. What is a double blind design? • In this type of experiment, information is withheld from the participants and the researchers in order to reduce bias.

  31. Types of Experiments • Quasi-experiments: different from true experiments because the allocation to groups is not done randomly. • Field Experiments: are conducted in a real life setting. The researcher can manipulate the IV but outside influences cannot be controlled. • Natural Experiments: the researcher has no control of the IV or the DV.

  32. Correlational Studies • In this type of study no variable is being manipulated. • Two or more variables are measured and the relationship between them is mathematically quantified. • A correlation is the measure of linear relationship between the two variables.

  33. Statistical Significance Effect Size • The absolute value of the correlation coefficient is the effect size. • This shows the likelihood that a correlation of this size has been obtained by chance. • The sample size can effect the results and a smaller sample may not yield the same results of the original experiment.

  34. Limitations of Correlational Studies • The Third Variable Problem- a third variable may exist that correlates with X and Y. • Curvilinear Relationships-sometimes variables are linked non-linearly. This means the correlation can increase and decrease causing a curve. • Spurious Correlations: The study involves calculating multiple correlations between multiple variables. Some correlations could be due to random chance.

  35. Ethics in Psychological Research • Informed Consent: Participants must be voluntary and full understand the nature of their involvement. • Protection from Harm: participants should be protected from mental and physical harm at all times. • Confidentiality: Participation is confidential and results are not connected to a specific individual.

  36. Withdrawal: it must be very clear to the participants that they can leave the experiment at any time for any reason. • Deception: in many cases the aim cannot be revealed to the participants. Researchers should keep deception to the minimum. • Debriefing: After the study has concluded the participants should be informed about its nature and true aims.

  37. Cost-Benefit Analysis • Cost-Benefit Analysis: sometimes the participants cannot know the true aim and consent cannot be obtained prior to the experiment. • In some cases the experiment can potentially reveal information that can help a lot of people. • In most countries there are ethics committees who determine the cost-benefit and resolve ambiguous issues and approve research proposals.

  38. ETHICAL CONSIDERATIONS • Investigators must consider the ethical implications and psychological consequences for research participants. • Consent • Deception • Debriefing • Withdrawal from the investigation • Confidentiality • Protection from mental and physical harm • Observational Research

  39. Ethics of Animal Experimentation • This topic has been long debated in many fields. • Animals often times do suffer during experimentation. • Animal rights activists call for an end to the use of animals in experiments. • Scientists argue that advancements in science and medicine that better humankind could not have been made without the use of animals.