Introduction to Unit 2 Psychology Unit 2 Research

Introduction to Unit 2 Psychology

Unit 2 • Research methods • Memory • Intelligence • Abnormality

Research Methods • Research methods is a fundamental part to studying psychology and within this topic we will explore the different research methods employed by psychologists to carry out research. We will look at the structure of a psychological report in preparation for students carrying out their own research. We explore statistical analysis using this to draw conclusions within research. •

Memory • This topic explores different models of memory in explaining how we store information in the brain. In addition to this we also look at reasons why we forget.

Abnormality • We explore depression and schizophrenia in this topic focusing on explanations of the disorders. We also learn about modern day treatments for these illnesses comparing their effectiveness in rehabilitating people.

Intelligence • This topic looks at theories of intelligence and explore evolutionary psychology. We explore how species have evolved and adapted to aid survival and how brain size is relative to the species.

Assignment 3 • 2000 word Research Project • Due w/c 21 st April • Investigate one model of memory and report your research findings in a formal academic report.

Assignment 4 • 2 hr Exam • 3 rd of June • Will be to do with Depression and Intelligence

Introduction to Experiments • The aim of today’s lesson is to investigate the use of laboratory experiments in psychology.

Carrying out research in psychology: Aim • In order to carry out a study we must firstly decide upon the aim. • The aim is a statement of what we are intending to research. • For example: to investigate the effects of binge drinking in the North East amongst different age cohorts.

Hypothesis • Before we carry out research in psychology we write a hypothesis. • A hypothesis is a specific and scientific statement of what we are intending to find. • There are two different types of hypotheses which we write: Alternative hypothesis and Null hypothesis

Alternative hypothesis • This is a precise statement which always states that a difference will be found between the groups being studied. • EG There will be a difference in the amount of binge drinking in different age cohorts in the North East

Null Hypothesis • This is a precise statement which always states no difference will be found amongst the groups being studied. • We also usually write at the end of a null hypothesis ‘any differences found will be due to chance’ • EG There will be no difference in the amount of binge drinking in different age cohorts in the North East

Directional or non-directional • There also two different types of alternative hypothesis: directional and non-directional. • A directional hypothesis will always state the precise direction in which the results will go in. • Hint! Directional hypotheses always have words in them such as more, less, increase, decrease to indicate direction

Non directional • A non directional hypothesis will state that a difference will be found between the two groups but doesn’t state where that difference will be.

What is an experiment ? • An experiment is a controlled situation in which the researcher manipulates one variable to discover its effect on another variable, while the other variables are held constant.

Variables • In any experiment there must be two “variables” • The independent variable is what we manipulate • And the dependent variable is the result/what we measure because it depends on what we do !

Jacobs: General Theory • “Sort Term Memory has a limited capacity” • This is a sensible idea, but it doesn’t give us any ideas about how we will test the hypothesis, the general shape of the experiment • So we need an experimental hypothesis, a starting point for the actual experiment

Jacobs: Experimental Hypothesis • • Independent Variable affects Dependant Variable So…. Number of items affects chance of remembering But we still need to be more exact – what items will we use and how will we measure the chance of remembering? • We need exact details….

Operational Hypothesis • Puts the research hypothesis into operational terms- things we can measure and record

OK – I’ve thought about all the variables – now let’s experiment

Laboratory Experiments • An experiment is a controlled situation in which the researcher manipulates one variable to discover its effect on another variable, while all the other variables are held constant. • We will begin with laboratory experiments, which are the closest to “pure science” because they give us the most control over those variables

Labs • Advantages of lab experiments • In a lab it’s easy to control the independent variable. • All other variables can be “held constant” • The experiment can be replicated at any time in the future. • Disadvantages of lab experiments • May lack ecological validity • (This means what happens in the lab may not be true to life. ) • Some situations simply cannot be created in lab conditions. • (Suppose we want to study why people commit suicide )

Experimental Design • There are three basic ways to compare run a psychology experiment. • These are called experimental designs. Independent measures design Repeated measures design Matched pairs design

Sometimes we need one group • Suppose we were studying the effect of brain surgery on a particular psychiatric illness. • It makes sense that we would want to study the same group before and after the surgery, so we could see if they had improved. • So this would have to be a repeated measures design – test the participants before AND after.

But in many cases a repeated measures design would be spoilt by “order effects” • Some things are just not the same the second time around: • The situation may only happen once in a person’s life – like learning to read • People may get better at the task with practice • They may get worse due to boredom and fatigue • They could work out the aims of the experiment and respond accordingly – demand characteristics. • So we would need two groups

This would be an independent measures design: • Experimental Group • Control Group: • This is a group that is not exposed to the independent variable.

Sometimes neither method works: • Suppose we wanted to test a new method of teaching maths. • We would teach one group of kids with the old method and we would teach one group with the new method. • We couldn’t use both methods with the same group – why not ? • But what if one group was just better than the other ? • So here we would use a Matched Pairs Design – we use two groups, but we make sure that the people in each group balance each other up.

Matched Pairs Design • Does anyone remember “picking teams” when you played games ? • Matched pairs is a bit like that. • The group are divided up as equally as possible. • The only problem is with psychology experiments it might much more be difficult to work out who is good at what.

Whole class activity: • Going back to that alcohol study • The hypothesis might be that drinking alcohol made people louder, less inhibited, more easily amused. • Alcohol is the IV • Level of conversation is the DV • But which design would we use? • How many groups would we need?

One group or two ? Could we use a repeated measures design ? • We could use one group of people. • On Friday night we give them alcohol and record their behaviour. • On Saturday we give them non -alcoholic drinks and record their behaviour. • Then we compare the two recordings. • But they could be more relaxed on Saturday because they haven’t been to work. • They could be hung over from the Friday experiment, • They may not even turn up ! • All these things distort the results.

One group or two ? Could we use an independent measures design ? • We could use two groups of people • We could give one group alcoholic drinks. • We could give the other group non-alcoholic drinks. • Then we could compare the behaviour of members of each group • But one group may have more people who are naturally outgoing. • One group may have an alcoholic. • Maybe someone just got the sack or had some bad news about their health. • All these factors could change the results

One group or two ? What about matched pairs ? • Our third option is to balance up the groups by picking people who are similar. • So each team gets a loud person. • Each gets a quiet one. • Each gets a heavy drinker • But how difficult is that going to be when we are dealing with complex psychological issues?

Order effects • No matter what design you use there can still be problems with order effects. • Suppose you wanted to see whether different music made people stay on a slot machine longer – by the time they move on to the second machine they could already be bored and lose interest. • This is a simple example of an order effect.

Counterbalancing • These problems can be dealt with by asking your subjects to carry out the conditions in a different order, and so balance out the order effects. This is called counterbalancing. • Half of the group could do Condition A, followed by condition B • The other half could do Condition B followed by Condition A • Just remember ABBA

ABBA

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