ISC- GRADE XI HUMANITIES ( ) PSYCHOLOGY. Chapter 2- Methods of Psychology

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1 ISC- GRADE XI HUMANITIES ( ) PSYCHOLOGY Chapter 2- Methods of Psychology OUTLINE OF THE CHAPTER (i) Scientific Methods in Psychology -observation, case study, surveys, psychological tests, experimentation steps. Psychological tests and their uses. The application of scientific methods in the study of behaviour. What is meant by scientific observation? controlled and uncontrolled observation; longitudinal and cross-sectional studies; the case history method; the experimental method - variables and controls - steps in an experiment; surveys and use of questionnaires/self reports. Meaning of samples - random, biased, representative population. Psychological tests - definition, uses. (ii) Interpretation of research results use of statistics in interpretation of data understanding of why statistics is used (descriptive & inferential). Basic statistical concepts statistics, sample, population. Why statistics is used in Psychology - interpretation of findings: describing and summarizing data, comparing individuals/ groups, investigating relationships between variables, predicting. Descriptive statistics - for summarizing scores. Inferential statistics - to determine whether observed differences between groups are likely/unlikely to have occurred by chance. How scores are grouped into frequency distributions; central tendency of a frequency distribution - mean, median, mode and when each measure is used; dispersion: the extent to which scores are spread out - range, variance, standard deviation; why both central tendency and variability are important in psychology. ( 1 )

2 i. Scientific Methods in Psychology 1. Systematic Observation: A basic method of science in which the natural world, or various events or processes in it are observed and measured in a very careful manner. Naturalistic Observation: A research method in which behaviour is studied in the settings where it usually occurs. Also known as uncontrolled observation. Scientific Observation- The researcher decides where the observation will take place, at what time, with which participants, in what circumstances and uses a standardised procedure. The researcher systematically classifies the behavior they observe into distinct categories. Scientific observation is reliable and more standardized than general observation. Also known as controlled observation. It is natural, flexible and economical. The data obtained from structured observations is easier and quicker to analyze It is suitable for studying the developmental characteristics of children s habits, interests, and other personality traits. It can prove useful only for collecting data on the observable behavior of individual not the subjective state of mind. The researcher might be subjective with the results of the study, hence loses the objective nature of a psychological research. This method is dependent on time and place, and hence it lacks replicability of the natural situation. It cannot establish cause and effect between the variables. 2. Case-study Method: A research method in which detailed information about individuals is used to develop general principles about behaviour. The researchers then use this information to formulate principles or reach conclusions that, apply to large numbers of persons- to all human beings. ( 2 )

3 It seems to provide insights into various aspects of behavior where individuals can be studied over a long period of time. These cases involve individuals who experienced specific kinds of damage to the brain, showed certain kinds of memory loss. If the persons studied are unique, it can be misleading to generalize from them to other human beings. There is a risk of being emotionally involved with the individual cases studies and as a result, one might lose their scientific objectivity. 3.Survey Method A research method in which large numbers of people answer questions about aspects of their views or their behaviour. Here, instead of focusing in detail on a small number of persons, researchers obtain a very limited sample of behaviour from large numbers of individuals, usually through their responses to questionnaires. Sometimes, a self-report can also be used. A self-report is any method which involves asking a participant about their feelings, attitudes, beliefs and so on. Examples of self-reports are questionnaires and interviews; self-reports are often used as a way of gaining participants' responses. Surveys are used for many purposes to measure attitudes towards specific issues, voting preferences, and consumer reactions to new products. Surveys can also be repeated over long periods of time in order to track changes in public opinion or other aspects of behaviour. For instance, surveys of job satisfaction-individuals attitudes toward their jobs have continued for more than forty years. This method involves use of questionnaires and reports. ( 3 )

4 Information can be gathered quickly and efficiently from many thousands of persons. Since surveys can be constructed quickly, public opinion on new issues can be obtained almost as soon as the issues arise. Disadvantage: Another issue deserving careful attention is the way in which surveys are worded. Even changing a single word in a question can sometimes shift the meaning-and strongly influence the results. Some people may find it hard to convey feelings in survey questions and maybe unable to decide 4. Correlation Method: A research method in which researchers attempt to determine whether and to what extent different variables are related to each other. Some variables are related to each other. As one changes the other appears to change too. For instance, as people grow older, they often seem to gain weight, that when interest rates drop, the stock market rises, and that the richer the people are the more conservative they tend to be. When such relationships between events exist, we say that the events are correlated with each other. This means that as one changes, the other tends to change too. The ability to make such predictions is one important goals of science and psychologists often attempt to make predictions about human behaviour. In the correlational method, make careful observations of each variable and then performing statistical analysis to determine whether and to what extent variables are correlated-to what extent changes in one are related to changes in the other. Correlations range from to and the more they depart from zero, the stronger the correlation. E.g. a correlation of is stronger than one of Positive correlations indicate that as one variable increases, the other increases too. For instance, the greater the number of hours students study for their psychology tests, the higher their grades tend to be. Negative correlations indicate that as one variable increases, the other decreases. For example, the less satisfied people are with their jobs, the more likely they are to search for another one to leave. ( 4 )

5 Correlation coefficient: A statistic indicating the degree of relationship between two or more variables. It can be used to study a large group of dat. It can help in understanding the relationship between two variables. It cannot establish a causal relationship between the variables. 5. Longitudinal studies where the differences in an individual or group of some individuals are studied over a long span of time. For example, by learning the pattern of growth and development with regard to physical, mental, emotional, social or moral dimensions of personality, we can study a particular infant or a number of infants as they normally grow and develop through successive ages. Advantage: It allows the researcher to study in detail about the individuals. They are effective in determining variable patterns over time. Disadvantage: However, this type of study would require quite a long span as the researcher has to wait for the normal course of development to occur. It is time consuming. Cross- sectional studies is when we study the different individuals across different age groups to determine the pattern of growth and development at different ages. Thus this takes place at a single point of time. Advantage: It gives the understanding about what is happening with the person at present. Data on all variables is only collected once and can be collected quickly. Disadvantage: It does not help in predicting that one variable causes the result or change in the other variable. ( 5 )

6 It cannot be used to analyze behavior over a period to time. 6. Experimental Method: The steps include: 1. On the basis of existing evidence a theory is formulated. Theories are frameworks for explaining various events or processes. 2. This theory which consists of some basic concepts and statements about how these concepts are related, helps to organize existing information and makes predictions about observable events. 3. These make predictions known as hypotheses derived from theories, are then tested by actual observations- by research. 4. If results of new observations are consistent with theory, confidence in it is increased. If they are not, the theory is modified and further tests of its predictions are performed. 5. Ultimately, the theory is accepted as accurate or rejected as inaccurate. Experimental method is a research method in which researchers systematically alter one or more variables in order to determine whether such changes influence some aspect of behavior. This involves two steps: 1. The presence or strength of some variable believed to affect behaviour which is systematically altered. 2. The effects of such alterations are carefully measured. For instance, exposure to a low amount of the variable should result in one level of behaviour, while exposure to a higher amount should result in a different level. The factor systematically varied by the researcher is termed independent variable, while the variable that is measured in an experiment is dependent variable. The researcher can then carefully measures the research participants behaviour to determine whether it does in fact differ depending on the level of independent variable to which they are exposed. To illustrate the basic nature of experimentation in psychological research, let s examine the possible effects of magnets on muscles or joint pain. One way in which a psychologist can study this is through the experimental method. ( 6 )

7 First, the psychologist would recruit persons who had considerable muscle or joint pain as participants in the research, through ads etc. In order to provide clear information about the cause and effect relationships, experiments must meet two key requirements. The first involves random assignment of participants to conditions. This means that all participants in an experiment must have an equal chance of being assigned to each group in the study, i.e. Experimental Group (EG) and Control Group (CG)- an equal chance of being exposed to each level of the independent variable. The reason for this is if participants are not randomly assigned to each condition, it may later be impossible to tell whether differences in their behavior stem form differences they brought with them to the study, from the impact of IV or both. The second requirement is: to as great a degree as possible all factors other than the independent variable that might also affect the participants behavior must be held constant. Consider what might happen in the study of magnets if those who get the real magnets are treated in a kind and soothing manner by the experimenter while those who get the non-magnetic disks are treated in a rude and harsh way. Then the ones who receive magnets will report less pain. Why? We can t tell because of confounding variables- confusion that occurs when factors other than the independent variable are permitted to vary across experimental conditions, can invalidate the apparent results of an experiment. To the extent that variables other than the independent variable are permitted to change in an experiment, the value of the study may be greatly reduced or eliminated. One important source of confounding is the subtle differences in experimenters behaviour that can influence research participants. For instance, a researcher who believes that magnets do have beneficial effects may act in a slightly friendlier or more reassuring manner toward participants who receive real magnets than those who do not. This can result in experimenter effects/bias- the unintended effects, caused by researchers on participants behaviour, and they can be deadly to the scientific value of a research project. Techniques used: ( 7 )

8 The Single-Blind research method is a specific research procedure in which the researchers (and those involved in the study) do not tell the participants if they are being given a test treatment or a control treatment. This is done in order to ensure that participants don't bias the results by acting in ways they "think" they should act. Many studies employ a double-blind procedure, in which the researchers who have contact with the participants do not know the hypothesis under investigation. Or the conditions in which the participants have been assigned. It is used to establish the cause and effect relationship. It can be replicated, generalized and is scientific in nature. It cannot be used to study all kinds of behavior. It is costly and time consuming. It is not possible to control all confounding behaviour. PSYCHOLOGICAL TESTS: A psychological test is "an objective and standardized measure of a sample of behavior". A psychological test is a structured technique to generate selected sample of behavior. Uses: It is used for hiring and recruitment It is used in schools and educational settings for measurement of IQ and Personality tests. It is used to identify abnormal or psychological problems. Types of test: 1. Intelligence Tests: They measure one s ability to understand the reasoning and problem solving skills and the ability to deal with the environment. E.g. Stanford-Binet Intelligence Test based on age. ( 8 )

9 Wechsler Test it is based on test items. 2. Interest tests: They attempt to match the interests of persons in careers. This also helps in giving a perfect fit for a job. 3. Personality Tests: These assess the characteristics that of a person. a. Objective tests: are paper pencil tests that have the options of a person answering in yes or no e.g. questionnaires and Minnesota Multiphasic Personality Inventory (MMPI) b. Projective test: These are subjective tests of personality. E.g. Rorschach Inkblot Test and Thematic Apperception Test 4. Aptitude tests and Achievement Tests: are designed to measure one s aptitude and achievement in the given filed and how much knowledge has one acquired. E.g. in math, comprehension. (ii) Interpretation of research result Why statistics is used in Psychology? interpretation of findings describing and summarizing data, comparing individuals/ groups, investigating relationships between variables, predicting behaviour Statistics: A branch of mathematics concerned with describing and interpreting data. Population: a collection of subjects that share a common characteristic. Sample: is a sub-set or a portion of population. It has to represent the population in order to be able to generalize the results. Types of Sample: ( 9 )

10 Random sample: A sampling method in which all members of a group (population or universe) have an equal and independent chance of being selected. Biased sample: In research method, sampling bias is a bias in which a sample is collected in such a way that some members of the intended population are less likely to be included than others. If this is not accounted for, results can be erroneously attributed to the phenomenon under study rather than to the method of sampling. Representative sample: A representative sample is one that has strong relationship to the target population the sample is meant to represent. That is, the characteristics of the sample have to match those of the group at large, so the sample to represent the group well. This will help to generalize the results to the entire population. Descriptive statistics: Statistics that summarize the major characteristics of an array of scores. Frequency Distribution: The frequency with which each score within an entire distribution of scores. Measures of Central Tendency: It represents the middle (or center) of a distribution of scores. Mean: A measure of central tendency derived by adding all scores and dividing by the number of scores. Properties: Advantage: It is sensitive to all of the scores. If one score in the distribution is changed, the mean will change too. Median: A measure of central tendency indicating the midpoint of an array of scores Properties: It is not sensitive to all the scores. It is most useful with skewed distributions. How to calculate the Median: Put all the numbers in numerical order. If there is an odd number of results, the median is the middle number. ( 10 )

11 If there is an even number of results, the median will be the mean of the two central numbers. Mode: A measure of central tendency indicating the most frequent score in array of scores. Properties: There can be more than one. We can have bi or tri-modal distributions. Measures of variability or dispersion: A measure of variability for a data distribution is a number that conveys the idea of spread of the values in the data set around the mean. Range: The difference between the highest and lowest scores in a distribution of scores. Easy to calculate Takes into consideration extreme score The extreme scores could distort range. We cannot know whether most scores occur at the extremes of distribution. Variance: A measure of dispersion reflecting the average squared distance between each score and the mean. It is less distorted by extreme scores. It helps to understand how are the scores distributed around the average. It only relates to about 50% of the data, ignoring the rest. It is tedious to calculate Standard Deviation: A measure of dispersion reflecting the average distance between each score and the mean. ( 11 )

12 It is the most sensitive measure of dispersion as it is uses every score in the data and is not very distorted by the extreme scores. It considers all scores in the data. It is strenuous to calculate the SD. It does not give accurate score in a skewed data. Why both central tendency and variability are important in psychology? Measures of central tendency allow us to understand how closely the scores are related to the mean or average. Measures of variance allow us to understand how varied or separated the scores are from the mean or average. Inferential statistics: Statistical procedures that permit us to determine whether differences between individuals or groups are ones that are likely or unlikely to have occurred by chance. Suppose that a psychologist conducts an experiment to examine the impact of mood on memory. To do so, he exposes one group of participants to conditions designed to place them in a good mood. They watch a very funny video. The second is exposed to a neutral tape- one that has little impact on their mood. Both groups are then asked to memorize list of words, some of which refer to happy events like, party and success. Later, both groups are tested for recall of these words. Results indicate that those who watched the funny tape remember more happy words than those who watched the neutral, in fact those in the first group remember 12 happy words, whereas those in the second remember only 8- difference of 4.0, is this difference a real one? Inferential statistics begins with the assumption that there is no difference between the groups-that the mean of this distribution is zero. For a particular experiment or set of observations, researchers compute the odds that the obtained difference is due to chance sampling. The result is stated as a probability (p) or estimation that the ( 12 )

13 difference obtained is a chance one arising from sampling bias. For instance, if the p value is <0.01 there is less than 1 chance out of 100 that the difference obtained was due to chance sampling factors. These are pretty good odds, so the psychologists who made those observations would conclude that sampling bias was not the reason for the group differences. The difference between the groups is said to be statistically significant, because the odds of its being due to chance sampling bias are so low. In practice, odds of 1 in 20, or p values of 0.05 (5 out of 100) are usually accepted as statistically significant. Differences with higher odds (p = 0.10 for example) are said to be non-significant, meaning that chance sampling factors cannot be ruled out with confidence. Bibliography: Baron, R; Misra, Girishwar, Psychology 5 th Edition Pearson Education Inc, 2002 Morgan, C; King. R, Introduction to Psychology, 7 th Edition, Tata McGraw-Hill Edition, 2006 HOW TO PREPARE FOR THE CHAPTER 1. You are required to refer to your three textbooks (Morgan and King, Baron and Mangal) while preparing for this chapter, in order to gain a deeper understanding and prepare for your examination. 2. These notes are guidelines and are by no means ideal answers. You must supplement your answers with relevant examples wherever required as per the marks allotted in the question paper. Question Bank- Objective Questions 1. What is meant by systematic observation? 2. Define case study. 3. Define survey method. 4. What is the difference between longitudinal and cross-sectional studies? 5. What is meant by biased sample, representative sample and random sample? 6. Write the uses of statistics in psychology. 7. Define the terms- statistics and population. 8. What is the importance of measures of central tendency measures of variability? 9. Write the definitions of Descriptive and Inferential statistics. 10. Explain the concept of Mean. 11. Explain the concept of Median. 12. Explain the concept of Mode. 13. What is meant by Range? 14. What is meant by Variance? 15. What is meant by Standard Deviation? ( 13 )