- are there age and sex differences in terms of levels of depression?
2 way between groups of ANOVA
ANCOVA
a statistical method of introducing random assignments when it was not possible to do so at the design stage
Dependent Variable (DV)
The outcome or variable of interest that you want to compare across different groups.
Independent Variable (IV)
The categorical variable that defines the groups being compared.
- differences between groups
2 grps- Pearsons correlation
3+ grps- ANOVA
categorical variables
2 types:
nominal variables( e.g. male or female)
ordinal variables(e.g. poor, good, excellent)
- to determine whether there is a relationship between short term memory span and reading ability
conduct correlation biviarate analysis
- to determine if there are differences in short term memory span across three class groups: (1) junior infants (2) senior infants (3) first class
conduct one way between groups ANOVA
correlation analysis
nature of relationship that exist between 2 variables
regression analysis
a special case of correlation analysis which is used for the purposes of prediction.
multiple regression analysis
whether a particular predictor variable is still able to predict an outcome, when the effects of another variable are controlled for/ used to investigate the relationship of multiple predictors with one continuous outcome variable
binary logic’s regression
used when the categorical criterion variable has 2 levels eg. smoker vs non smoker
multinomial logistic regression
used when the categorical criterion variable has 3 or more levels e.g. mild/ moderate/ severe depression
t tests
compare the mean values on some continuous variable for 2 groups or 2 occasions
independent t tests
compare the mean scores of 2 different groups
paired t tests
compares the mean scores of 2 different groups of people on 2 different occasions or conditions
- is there a significance difference in PTSD scores between males and females?
conduct an independent t test
- is there a statistically significant change in prisoners criminal social identity scores after 2 years in prison sentence in high security prison?
conduct a paired t test
ANOVA
tells us the difference between the variances of the groups e.g. comparing fitness levels between amateur, semi professional, professional
one way between groups ANOVA in spss- write up
one way between groups ANOVA was conducted to determine if there were differences in levels of… scores/ participants were divided into groups according to…./ there was no significant difference in levels of…..scores for the groups, f (…)=…, p=…./ effect size (eta squared= …)/ post hoc comparisons using turkey HSD test indicated that the mean scores…(m=….,sd=….)
correlation bivariate in spss- write up
check sig(2 - tailed) = p value if p<0.05 is means it is statistically significant/ check r-value/ positive or negative direction/ large strength( 0.5-1), small strength(0.10-0.28)
one way between groups ANOVA in spss- write up(short)
test of homogeneity of variance- if less than 0.05 f/sig
ANOVA table- also if less than 0.05
effect size- 0.01 small effect/ 0.06 medium effect/ 0.14 large effect
