Consensus Calculation Example - Radio button/Combobox

 
Surveylet offers different statistical measures for Consensus and Group Stability calculation, which settings are configurable for survey questions individually. Depending on the type of the question, different options are available for us to choose from. See Consensus Measurement for more information.
 
This is an example for the Radio Button or Combobox question type when Consensus measurement is set to use the Mean statistic, and Group Stability is set to use the Coefficient of Variation (CV) statistic. 
 
In this example below, we will calculate the consensus score, choice of consensus, group stability and consensus status.
 
For the sample question, we ask the likelihood of an event happening on a 5-point Likert scale :
 
rank 1 - Very Unlikely
rank 2 - Unlikely
rank 3 - Neutral
rank 4 - Likely 
rank 5 - Very Likely
 
We have 9 panelists who submitted a response to this question. Here are their answers:
 
user name
user selection
user score
User A
Very Unlikely
1
User B
Very Unlikely
1
User C
[I don't know]
 
User D
Neutral
3
User E
Neutral
3
User F
Very Likely
5
User G
Very Unlikely
1
User H
[I don't know]
 
User I
Unlikely
2
 
Let's calculate stability and consensus from the above data set.
 

Group Stability Calculation 

 
 
There are 9 participants who answered the question.
2 of the 9 participants selected the [I don't know] option, therefore their answers are removed from calculation.
7 of 9 participants provided answers to the question.
 
Number of users: 7
Total sum of all user scores: 16
Mean (Arithmetic Mean) = 16 / 7 = 2.285714286
Standard Deviation (StDev Sample) = 1.496026483
Coefficient of Variation (CV) = StDev / Mean = 1.496026483 / 2.285714286 = 0.65451158623 = 65.45%
Group Stability = 100% - CV = 100% - 65.45% = 34.56%
 
Group Stability is rounded up to the nearest whole number, when displayed in the stability gauge.
 

Consensus Score Calculation

 
The consensus score is calculated from the Average (Arithmetic Mean), which is 2.285714286 for this question (as calculated above). The 2.285714286 value means that the group consensus is between rank 2 (Unlikely) and rank 3 (Neutral).
 

Choice of Consensus Calculation

 
The Consensus Score value of 2.285714286 is rounded up to its nearest integer number to get the ranking position of the Choice of Consensus, which is in this case 2 - "Unlikely".
 

Stability Threshold Value

For this example, the Consensus Threshold value which is set to 50%, meaning that the group stability value must be greater than 50 for the group consensus to be established.
 

Consensus Status Calculation

 
Now we need to calculate the status of consensus, which is based on the Consensus Threshold value which is 50%. This means that we need over 50% group stability for the group-decision for this question to be flagged as Agreement, otherwise it is flagged as Disagreement. Since the group stability is 34.56% which is lower than the required 50%, the group did not reach agreement.