Tutorial 2 Data Collection, Coding, and Analyse

Question 1

What is sampling?

Answer 1

• Sampling is a process used in statistical analysis in which a predetermined number of
  observations are taken from a larger population.
• By performing an analysis on a selection of the elements in a population, we may draw
  conclusions about the entire population

Question 2

Why do we sample? (3)

Answer 2

• Because of cost considerations (fast and cheaper)
• Because researchers cannot analyze the whole population
• Samples can produce sound results if proper rules are followed for the draw

Question 3

What are the four steps of the sample process?

Answer 3

1. Define the population
2. Determine the sampling frame
3. Select the sampling procedure
4. Determine the sample size

Question 4

What is the advantage of a multi-item scale compared to single-item scale? (5)

Answer 4

• Less variables in your regression formula
• Multi-item scale mostly has a higher reliability compared to a single item scale.
• Higher construct validity & criterion validity
• More precise segmentation possible
• In case of missing values, imputation methods based on correlations between indicators of the same construct is possible.

Question 5

What kind of analysis would we perform if we asked a ‘simple’ yes or no question (1-0 coded variable)?

Answer 5

Logistic regression

Question 6

Define correlation

Answer 6

Correlation –> when two or more events are related to each other and change together.

Question 7

Define causality

Answer 7

Causality –> when one event contributes to the production of another event. Where the cause is partly responsible for the effect, and the effect is dependent on the cause.

Question 8

Give an example of a case where correlation is present between two variables but for which a causal relationship is quite unlikely

Answer 8

• Correlation between ice cream sales and sunglasses sold.

or

• The amount of firefighters sent to a fire, and the amount of damage that is done.