Unit 1 - Extra Bits Flashcards
(Extra Bits) What does descriptive statistics relate to?
Ways of summing up and presenting your findings.
(Extra Bits) What can descriptive statistics be contrasted to? Give an example.
Inferential statistics, i.e. statistical tests.
(Extra Bits) What does inferential statistics relate to?
Working out what your findings are telling you (i.e. what you can infer/conclude from them, principally in terms of which hypothesis has been supported).
(Extra Bits) State the 6 ways of displaying data.
- Frequency tables (tally charts)
- Line graphs
- Pie charts
- Bar charts
- Histograms
- Scatter diagrams
(Extra Bits) What level of data do pie charts work well with?
Nominal level data.
(Extra Bits) What do pie charts enable the researcher to present?
Percentages from within an overall total and show proportions of a whole.
(Extra Bits) What are line graphs useful for showing?
Change over time.
(Extra Bits) What do histograms convey?
Information about the frequency with which something occurs, through the area of the bars.
(Extra Bits) What do bar charts convey?
Information about frequencies through the height of the bars.
(Extra Bits) When and why would you use a histogram?
When you have continuous data and want to emphasise the role of category width a well as frequency.
(Extra Bits) What do inferential statistics enable you to work out?
Which hypothesis (null/alternative) has been supported by the data from either an experiment or a correlation study. They enable you to draw conclusions/inferences from your findings.
(Extra Bits) What non-parametric inferential test would you use if you had: nominal data & a test of difference with unrelated data (i.e. independent measures)?
Chi Square test
(Extra Bits) What non-parametric inferential test would you use if you had: ordinal data & a test of difference with unrelated data (i.e. independent measures)?
Mann-Whitney U test
(Extra Bits) What non-parametric inferential test would you use if you had: interval/ratio data & a test of difference with unrelated data (i.e. independent measures)?
Independent t-test
(Extra Bits) What non-parametric inferential test would you use if you had: nominal data & a test of difference with related data (i.e. repeated measures/matched participants design)?
Binomial Sign test
(Extra Bits) What non-parametric inferential test would you use if you had: ordinal data & a test of difference with related data (i.e. repeated measures/matched participants design)?
Wilcoxon Signed Ranks test
(Extra Bits) What non-parametric inferential test would you use if you had: interval/ratio data & a test of difference with related data (i.e. repeated measures/matched participants design)?
Related t-test
(Extra Bits) What non-parametric inferential test would you use if you had: nominal data & a test of correlation)?
N/A
(Extra Bits) What non-parametric inferential test would you use if you had: ordinal data & a test of correlation)?
Spearman’s Rho Correlation Coefficient
(Extra Bits) What non-parametric inferential test would you use if you had: interval/ratio data & a test of correlation)?
Pearson’s Product Moment
(Extra Bits) State the 3 criteria that has to be met for using a parametric test.
- The data has to interval or ratio.
- The data has to have a curve of normal distribution.
- The variances should be similar.
(Extra Bits) What does an alternative hypothesis always predict?
A significant outcome (difference or relationship).
(Extra Bits) What does a null hypothesis always sate?
That any difference or relationship ‘could be due to chance factors’.
(Extra Bits) What is the standard level of significance?
1/20
(Extra Bits) If the standard level of significance is not reached, how would this be expressed, and what hypothesis would be supported?
p>0.05 (probability of results being due to chance is greater than 1/20). The null hypothesis would be supported.
(Extra Bits) If the standard level of significance is reached, how would this be expressed, and what hypothesis would be supported?
p≤0.05 (probability of results being due to chance is less than, or equal to, 1/20). The alternative hypothesis would be supported.
(Extra Bits) If the standard level of significance is exceeded, how would this be expressed, and what hypothesis would be supported?
The psychologist would express this by writing the highest level of significance that has been achieved by their results. The alternative hypothesis would have been strongly supported.
(Extra Bits) Explain what a type 1 error is?
The alternative hypothesis is accepted and the null hypothesis is rejected, and the behaviour shown was really due to chance.
(Extra Bits) Explain what a type 2 error is?
The rejection of the alternative hypothesis and acceptance of the null hypothesis when the independent variable is having a significant impact on the dependent variable.
(Extra Bits) Out of type 1 and type 2 errors, which mistake would researchers most likely make?
Type 1 because if you accept your alternative hypothesis you have a greater chance of your research being published (unethical reason).
(Extra Bits) What is this symbol: =
Equals