stats tests Flashcards
(20 cards)
characteristics of non-parametric tests
- 30 data sets or less
- data is not normally distributed
- ordinal or nominal
types of non-parametric tests
tests of difference = chi square, Mann-whitney U, Kruskal-Wallis
relationship = spearman’s rank
nominal data
names
ratio data
%, metres
interval data
celcius
ordinal data
categories eg. survey
characteristics of parametric tests
- more than 30 data sets
- data is normally distributed
- interval/ ratio scale
types of parametric tests
difference = t-test, ANOVA relationship = Pearson's correlation
interpreting regression analysis
- R^2 value to % shows the variability of one can explain the other
- F ratio- if greater than 1 can say that the explained is greater than the unexplained. Also compare F ratio to p value eg. F ratio is greater than 1 at 95% confidence level so the regression model is significant
- if p value is lower than 0.05 then at 95% confidence level the regression coefficient is statistically significant
- overall: comment on proportion of variability between the variables, explained variance, regression coefficient
overall, is the regression model viable in nature?
how to do a normality & null hypothesis question given output and p value
- state the null and alt hyp
- work out at 95% and say if significant
- see if you can say it’s NOT normally distributed
- 99% level
is it good to have an F ratio greater than 1?
yes- means that the explained is greater than the unexplained
what do you say if the F ratio is less than 1?
at (confidence level) the regression model is not significant
what does p < 0.05 mean?
the p value is less than 0.05
discontinuous data
ordinal and nominal (weaker)
continuous data
ratio and interval (stronger)
what is the t-statistic?
regression coefficient
what does Butler argue that participatory research is used for?
- include diverse voices
- understand varied ways of framing energy problems and solutions
what can qualitative methods provide?
- potential for important critical forms of engagement with processes of energy system change
- they can provide deeper (and different) understandings of the nature of the problem and what we might need to do to address it (Butler et al. 2018)
example of ethnography in research
in Danial Fisher’s research on asylum seekers in the EU, it enables the understanding of asylum journey beyond abstract numbers or narratives of pity
spearman’s correlation thresholds
0-0.19 very weak
- 2-0.39 weak
- 4-0.59 moderate
- 6-0.79 strong
- 8-1.0 very strong