quantitative- quasi experimental designs

Question 1

Definition of quasi-experimental design

Answer 1

Quasi-experimental designs are those in which participants cannot be randomly assigned to conditions
Or
A quasi-experiment exists whenever causal conclusions cannot be drawn because there is less than complete control over the variables in the study

Question 2

Threats to internal validity

Answer 2

all third variables 
-in a quasi experiment you can't randomly assign which means you are especially vulnerable to: 
history
maturation
selection bias
regression to the mean

so you match

Question 3

What are the advantages of quasi-design?

Answer 3

-increased external validity because you are working with real-world conditions

Question 4

2 types of quasi design

Answer 4

1. nonequivalent control group designs

2. interrupted times series design

Question 5

Nonequivalent control group deign

Answer 5

purpose: evaluate effectiveness of a treatment programme

Experimental group: observation 1 -> treatment -> observation 2

control group:
observation 1 -> observation 2

Question 6

best outcome for treatment effectiveness

Answer 6

the control group stays level and the experimental group improves

Question 7

how to rule out regression to the mean

Answer 7

if the line of the experimental group is heading to the control group line then it could be regression but if it is moving away then it is not regression

Question 8

Interrupted time series design

Answer 8

Observation 1, O2, O3, O4, Treatment, O5, O6, O7, O8

Question 9

iatrogenic

Answer 9

when the treatment causes the problem