Research Methods 1 - Level 5

Question 1

a-level

Answer 1

the probability of making a type 1 error (usually this value is 0.05).

Question 2

adjusted mean

Answer 2

in the context of the analysis of covariance, this is the value of the group mean adjusted for the effect of the covariate.

Question 3

alternative hypothesis

Answer 3

the prediction there will be an effect (i.e., that your experimental manipulation will have some effect or that certain variables will relate to each other).

Question 4

Analysis of covariance

Answer 4

a statistical procedure that uses the F-statistic to test the overall fit of a linear model, adjusting for the effect that one or more covariates have on the outcomes variable. In experimental research, this linear model tends to be defined in terms of group means and the resulting ANOVA is, therefore, an overall test of whether group means differ after the variance in the outcome variable explained by any covariates have been removed.

Question 5

Bar Chart

Answer 5

a graph in which summary statistic (usually the mean)is plotted on y-axis against a categorical variable on the x-axis (this categorical value could represent for example, groups of people, different times or different experimental conditions). The value of the mean for each category is shown by a bar. Different coloured bars may be used to represent levels of a second categorical variable.

Question 6

Bimodal

Answer 6

A description of distribution of observations that has two modes.

Question 7

Bonferroni correction

Answer 7

a correction applied to the α-level to control the overall type I error rate when multiple significance tests are carried out. Each test conducted should use a criterion of significance of the α level (normally 0.05) divided by the number of tests conducted. This is a simple but effective correction, but tends to be too strict when lots of tests are performed.