Up to 33% of total A level from Research Methods and Statistics Lesson 4 Research Methods and Statistics - Unit 2 – Also questions in Unit 1 & 3 Up to 33% of total A level from Research Methods and Statistics 10% of total A level from applying maths skills

Prep for lesson 5 Go to the ‘first two weeks 2018’ on psych205 and complete the ‘prep for lesson 5’ work for next lesson. Also…..

…. The Mathematics test You completed some mathematics homework over the summer Go to the VLE and click on the Icon on the year 1 psychology section. Once you agree to start this, you only have 30 minutes to complete it. The results will be logged and there will be a formal record of this attempt with your score. It is open now, and the deadline to complete this is 3.45pm on Wednesday 26th September Please note that the answers are very sensitive. Like the exam, if you forget to put a % after an answer asking for percentages, you will not receive a mark. Similar, watch out for advice on decimal places. Good luck.

Analysis of the experiment We are going to analyse our experiment today by… Collation of data Analysis of data Analysis of further patterns in data Can we support or reject the hypothesis Conclusions – does this support or refute informational social influence as a theory? Criticism of our experiment in terms of validity, sample technique, research design

Changed Answer on Question 4 Data Analysis Please have your data in front of you We are going to fill in this 2x2 contingency table (2x2 contingency table: it’s what this type of table is called). But first, can you think of a title for this table (all tables must have a well described title) Changed Answer on Question 4 Did Not Change Answer On Question 4 Quiet reflection Group estimate sheet

Changed Answer on Question 4 Data Analysis 2x2 contingency table showing how many participants did or did not change their estimates on a question about road length depending on weather they were exposed to group estimates or not The AQA exam board want students to give detailed titles to tables and graphs Changed Answer on Question 4 Did Not Change Answer On Question 4 Quiet reflection Group estimate sheet Such a common mistake. Please write ‘whether’

Changed Answer on Question 4 Data Analysis Lets collate the data: put your hand up if the cell applies to your participants (you should only put your hand up twice) 2x2 contingency table showing how many participants did or did not change their estimates on a question about road length depending on whether they were exposed to group estimates or not Changed Answer on Question 4 Did Nott Change Answer On Question 4 Quiet reflection Group estimate sheet

Now convert these scores into percentages Changed Answer on Question 4 Data Analysis Now convert these scores into percentages Click for hint on how to do this Cell score / total of all scores x 100 2x2 contingency table showing the percentage of participants who did or did not change their estimates on a question about road length depending on whether they were exposed to group estimates or not Changed Answer on Question 4 Did Nott Change Answer On Question 4 Quiet reflection Group estimate sheet

Now convert the actual scores into a bar chart Data Analysis Now convert the actual scores into a bar chart Detailed title: A bar chart showing the number of participants who did or did not change their estimates on a question about road length depending on whether they were exposed to group estimates or not Why would we use a bar chart with this data? Discrete data (in categories) Should the bars be separate or next to each other? Separate Should number of participants be on X or Y axis? Y axis Should the first bar be right next to the Y axis or a little distant apart? Apart Should you include a key? Depends on how well you have labelled your X axis

An example of what a bar chart should look like A bar chart showing the number of participants who did or did not change their estimates on a question about road length depending on whether they were exposed to group estimates or not

Analysis of the Results Given these findings, do you think we have an experimental effect? What should we do about our experimental hypothesis? support it or reject it. Why? Does our study support the theory of informational social influence? Why/why not?

Null and Alternative Hypothesis The null hypothesis: If the experiment does not have an effect, then both groups will have a similar number of people who have changed their answer. If this is the case, we would support a null hypothesis. Simply speaking “Nothing has changed”. The alternative to this is that there is an experimental effect and that “Something has changed”. This is known as the alternative hypothesis (sometimes called the experimental hypothesis) In an experiment, a psychologist will predict both a null hypothesis and an alternative hypothesis. Complex statistical analysis (see year 2) allows psychologists to support one or the other with a certain level of probability. More of that as the course progresses.

Hypothesis recap Hypotheses are statements that predict the outcome of an experiment. Hypotheses Experimental Directional Non-directional Null Predicts that there won’t be a difference between groups. Predicts which group (condition) of scores will be larger than the other. Used when there is strong evidence from previous research Predicts there will be a difference in scores (conditions) but not which group will be larger? Used when there is no previous research.

So which hypothesis should be supported? Null Hypothesis: There will be no difference in the number of participants who have changed their answer on a question about road lengths between those who have been given a group estimate during reflection, and those who were given no information during reflection Alternative Hypothesis: Participants given a group estimate to a question about road length are more likely to change an initial answer than participants who are given no group estimates to the question on road lengths.

Further analysis Sometimes its interesting to see if there are differences between certain groups Collate the data for males and females and convert into percentages. Any interesting findings? Collate the data for different age brackets and convert into percentages. Any interesting findings?

Critical Analysis A vital part of scientific enquiry is the critical analysis of each experiment. There maybe questions with the design of the experiment, the running of the experiment, even the statistical analysis of the data which means that psychologists make weak or even false conclusions Task: On the BWBs, write as many flaws in the study as you can think of and why you think it is a flaw. Do not hold back with this, it is an important part of scientific investigation, so stick the boot in! Example: The participants were tested in different environments. This means that there we cannot tell if the participants’ behaviour was influenced by their unique environment rather than the experimental conditions

Populations and Sampling Researchers cannot study all humans (7 billion) Researchers have to consider what their ‘target’ population is. This is sometimes determined by a specific grouping that researchers wish to know about (e.g. All people living in Brighton and Hove between the ages of 16 to 18). Usually, researchers cannot study all the target population either, so they will take a sample from that target population Its best to get a sample that is representative of the target population. In reality, this is very challenging and is rarely achieved. This leads to a biased sample, which then limits conclusions about the study.

The Sampling Method Stratified Opportunity Random Systematic Volunteer With Psychology A level, the use of 5 sampling techniques are considered. Decide which definition matches the terminology. A) All people within a target population have an equal chance of being selected B) Participants have responded to a request to take part in an investigation, for example, they have seen an advert in a magazine C) The researchers choose the nth person from the target population D) The researcher decides on categories (strata) that are really important to be represented in the sample. Once the strata are established, participants are randomly selected from each strata. The proportion of the sample within each strata must mirror that of the total target population E) A researcher will use anyone who is available (and agrees to take part) at that given moment Stratified Opportunity Random Systematic Volunteer

Answers Identify which sampling method goes with these definitions A) = Random: All people within a target population have an equal chance of being selected B) = Volunteer: Participants have responded to a request to take part in an investigation, for example, they have seen an advert in a magazine C) = Systematic: The researchers choose the nth person from the target population D) = Stratified: The researcher decides on categories (strata) that are really important to be represented in the sample. Once the strata are established, participants are randomly selected from each strata from the target population. The proportion of the sample within each strata must mirror that of the total target population E) = Opportunity: A researcher will use anyone who is available (and agrees to take part) at that given moment

Prep for lesson 5: Complete similar notes for all 5 sampling techniques using pages 30-32 in the information pack on psych205

Examples – on MWBs on your own Identify which of these examples go with which sampling technique (just write the words in bold for speed) A criminologist chose every 10th prisoner at Ford prison from the register in alphabetical order for a study on the treatment of prisoners in an open prison A social psychologist chose 14 broad categories of ethnicity and randomly assigned the correct proportion relative to the population of Brighton and Hove to each category Neurobiologists advertised in a health magazine for participants to help with an experiment into sleep deprivation A second year BHASVIC psychology student was allowed access to the complete BHASVIC student register. They assigned a number to each name, and selected 50 numbers using a computer with random number generating software, and choose a sample of 50 students A social psychology post-graduate asked his students if they would take part in a study on memory

Examples - MWBs Answers Volunteer: Neurobiologists advertised in a health magazine for participants to help with an experiment into sleep deprivation Systematic A criminologist chose every 10th prisoner at Ford prison from the register in alphabetical order for a study on the treatment of prisoners in an open prison Stratified: A social psychologist chose 14 broad categories of ethnicity and randomly assigned the correct proportion relative to the population of Brighton and Hove to each category Random: A second year BHASVIC psychology student was allowed access to the complete BHASVIC student register. They assigned a number to each name, and selected 50 numbers using a computer with random number generating software, and choose a sample of 50 students Opportunity: A social psychology post-graduate asked his students if they would take part in a study on memory

Your experiment Which sampling method did we use for our experiment? Opportunity sample Identify one advantage and disadvantage of this sampling method (use pages 30-32 in information pack if required) How might this affect the conclusions of your experiment?

Prep for lesson 5 There is a lot to do for lesson 5 Sampling homework (see previously) Definitions of Internal and external validity Reliability Experimental design