Lecture 5

Question 1

Factors influencing the a error

Answer 1

Size of the effect - the larger the measured effect the lower the probability of error

Dispersion of the measurement values - the greater the dispersion of the measurement values, the greater the probability of error

Sample size - the larger the sample, the lower the probability of error

Question 2

What statistical level should be set for power (1-B)

Answer 2

Objective: increase: the higher the values the higher the probability that one will also find an effect

Thresholds: value falls with a decreasing a level

Relevance: practitioners: searching for useful

To users: practitioners sometimes use higher significance levels than academics (eg <20%)

Question 3

Regressions coefficient concept

Answer 3

Regression coefficient concept is minimising the deviations of the actual observations from the regression line