Quantitative Research Analysis

Question 1

Define dependent and independent variables

Answer 1

Dependent Variable = The variable that is being measured

Independent Variable = The variable that is systematically manipulated by the
investigator.

Question 2

Explain the differences between nominal, ordinal, interval and ratio measurement scales

Answer 2

Nominal - categories named
Ordinal - categories named and ordered
Interval - categories named, ordered and intervals defined
Ratio - categories named, ordered and intervals defined, and true zero exists.

Question 3

Explain the difference between standard deviation and standard error

Answer 3

SD - variability within a sample
SE - variability across samples

Question 4

Explain the difference between type 1 and 2 statistical error

Answer 4

Type I error = rejecting the null hypothesis
when it is true

Type II error = accepting the null
hypothesis when it is false

Question 5

Explain what is meant by effect size

Answer 5

Effect sizes tell you how meaningful the relationship between variables is (which can also be how meaningful the distance between your result and the mean is) – indicating the practical significance of a research outcome.

Question 6

Explain p-values

Answer 6

P-values evaluate how well the sample data support the argument that the null hypothesis is true

Question 7

Explain the disadvantages of a large sample size

Answer 7

Resources.

Unnecessary testing.

Harder to detect smaller effects.

Question 8

Explain t-tests and its assumptions.

Answer 8

T-tests are used to determine if there is a significant difference between the means of two groups.

Assumes data is independent, normally distributed, and have similar amount of variance.

Question 9

State the two tails of t-tests

Answer 9

Two-tailed - only care about if two groups are different

One-tailed - if you wanna know if one population is greater or lesser than the other

Question 10

Explain when ANOVA would be used over t-tests

Answer 10

When the difference between means of more than two groups needs to be calculated.

Question 11

Explain the idea of sampling

Answer 11

Samples allow us to represent a population. To do so accurately, we must minimise sampling error and bias. We do this by randomising and collecting larger samples.