Research Methods - Biological Psychology

Question 1

What can you do with histograms?

Answer 1

Display your Frequencies

Question 2

What are the rules with histograms?

Answer 2

X Axis must be labelled frequency
Bars are coded so we know the group of tallies they stand for
Bars to touch
Blank space where frequency = 0

Question 3

What are descriptive statistics?

Answer 3

Analyse findings from a sample

Question 4

What are inferential statistics?

Answer 4

How sample’s resuults relate back to the target population where the sample was drawn

Question 5

Why are inferential statistics needed?

Answer 5

Are essential to see whether the results support the null hypothesis or rejecting it in favour of the alternative hypothesis

Question 6

Define the Mann-Whitney U-Test

Answer 6

For ordinal level data / experiments with independent groups design

Question 7

Define the Wilcoxon Test

Answer 7

For ordinal level data / experiments with repeated measures or matched pairs designss

Question 8

Define the Spearman’s Rho

Answer 8

For ordinal level data / Used for correlations

Question 9

Define Chi-Squared

Answer 9

For Nominal level data / Analysing independent variables in categories (i.e. most observations)

Question 10

How do you decide which test to use?

Answer 10

Step 1) Figure out the level of data collected (if nominal then, use Chi Squared)

Step 2)Is the study a correlation or a test of difference?(if correlation, then, use Spearmann’s Rho)

Step 3)Is the data independent or related?
(if independent groups design, then Mann Whitney - if otherwise, then Wilcoxon)

Question 11

How do you know is the data is nominal?

Answer 11

Data is nominal if researchers identify categories of response and simply count how many times they occur

Question 12

How do you know if the data is ordinal?

Answer 12

Data is ordinal if responses can be ordered from highest to lowest

Question 13

What the four levels of data collection?

Answer 13

Ratio level, interval level, ordinal level and nominal level data

Question 14

What is ratio level data?

Answer 14

A score on a scale.

The most important part of the data is that there is a meaning score of 0 (no data) which gives it a starting point.

Question 15

What is interval level data?

Answer 15

Also a score on a scale, but can go into negative figures (is used for things like temperature)
Has no fixed stating point

Question 16

What is ordinal level data?

Answer 16

A number score representing rank position (i.e. league tables) and can be turned into interval/ratio data by putting scores into rank order)
It demolishes distinctions between rankings
More psychological measures gather interval/ratio level data,so ranking is a must.

Question 17

What is nominal level data?

Answer 17

Puts participants into categories (categorical data i.e. tally marks) to produce frequencies and is easily turned to percentages
Interval/ratio level data can be turned into nominal by putting data into a frequency table in order to turn it into a histogram.

Question 18

What is the basic procedure for all inferential tests?

Answer 18

1) Calculate your observed value: meant to be as small as possible but in the case of Spearman’s Rho, it is the opposite (big as possible)
2) Choose your probability level: As these tests work out the likely-hood of your results as normality of results = acceptance of null hypothesis or very unlikely = refuting null for alternative hypothesis as shows a pattern at work
3) Find your critical value (part 1):Once selected a value for P and calculated your observed value, can consider a critical value table (different table for directional and non-directional hypothesis)

4)Find your Value of n or df: these are scores that represent the size of your sample (n = numbers of participants and df = degrees of freedom)
The more df, the more categories

5)Find your critical values (part 2): Compare observed values with critical value (found when counting along the table) to see if statistically significant

(Mann Whitney & Wilcoxon - U =or < critical value then is statistically significant
Chi Squared & Spearman Rho- id r =or > critical value then is statistically significant)

Question 19

How unlikely do results have to be before you take them seriously and treat them as a pattern?

Answer 19

Decision summed up by P (probability)

P