Data sources and weighting

We use data from different sources to get accurate data

Purpose
The purpose of having ratings on Jobindex is to give users an overview of the job market. Once they have seen a job ad, they would often like to find out more about the workplace. Jobindex works to promote greater job satisfaction in Danish companies, and we attempt to do so by giving our users the best, most accurate and complete overview of data on job satisfaction in Danish workplaces.

Star ratings
When a user completes a rating on Jobindex, they give their workplace between 1 and 5 stars. The stars are assigned within different categories, such as management, culture and meaningfulness, working environment and work-life balance. Next, the average of every user’s rating is calculated to get the user’s overall rating of the workplace.

We adjust all ratings by spreading out the star scale so that we use the entire scale. Without this adjustment, all of the large companies would end up in the middle of the scale with 3 or 4 stars. This is why we broaden the scale and translate the company ratings into a job satisfaction score on a 7-point scale from 0 to 6.

More specifically, the way we convert awarded stars to job satisfaction scores is as follows:

• 1 star equals a job satisfaction score of 0
• 2 stars equal a job satisfaction score of 1
• 3 stars equal a job satisfaction score of 3
• 4 stars equal a job satisfaction score of 5
• 5 stars equal a job satisfaction score of 6

Multiple data sources
In addition to the ratings on Jobindex, other data sources are also included in our calculations. We do so for two reasons:

1. We would like to assemble the most accurate and complete overview of the workplaces in Denmark
2. By having data from several different sources, we can better control that the data is not deceiving

Job Satisfaction Test
One of the sources is our Job Satisfaction Test, which is developed in cooperation with Ennova. The test gives rates all ratings on a scale from 0 to 100, which we then convert to a job satisfaction score on the 7-point scale.

QuickRatings
In addition to star ratings, where employees award stars overall and within a number of categories, we also offer users who have submitted their CVs the ability to provide a QuickRating for their former workplaces. This means that the user gives their workplaces an overall number of stars, i.e. an overall rating.

Jobberlife
Jobindex has bought the company Jobberlife, where we also receive ratings of workplaces in Denmark. These ratings are accompanied by 1 to 5 stars, and users are also able to give half stars as well.

Weighting of ratings over time
All ratings are weighted in relation to their age. Newer ratings are therefore given more weight than older ratings – and each is assigned a weight of one. Their weighting decreases over time in such a way that the difference in weight is greater between two ratings that are one and two years old than is the difference in weight between two ratings that are five and six years old.

A five to six-year-old rating will still, however, count for more than 50 %, as our data shows that job satisfaction changes at a very slow pace, and we would like to use all of the data we have on a workplace in our assessment of job satisfaction.

Ratings that stem from the Job Satisfaction Test or QuickRatings are only weighted half as much as a regular star rating. We do this because the Job Satisfaction Test is less direct and only measures personal job satisfaction, while QuickRatings measure the workplace overall and not on a nuanced level by category.

Fixed ratings
Further, we add in a number of fixed ratings in order to avoid giving companies top or bottom scores before we are sure. Even though most Danish workplaces are rather good places to work, if you take the average of what all employees think, there is a very big difference in what each individual employee in the same company thinks. There are very satisfied and very dissatisfied employees in every company. We do not want to criticise workplaces or name a workplace as one of the best in Denmark unless we have a sufficiently reliable, statistical basis upon which to assess the workplace.

Therefore, all companies, as a rule, are given what corresponds to 10 additional 3-star ratings in order to make the ratings at the top and bottom of the scale more reliable. This is called the Bayesian average: where you assume that a workplace is an average workplace until there is data to suggest otherwise. We do this to ensure that companies with very few ratings do not end up with a very high or very low score because of having so few ratings which are not statistically significant.

Without fixed ratings, workplaces with very few reviews will easily receive either 1 or 5 stars due to having so few ratings. With fixed ratings, the workplaces start out with 3 or 4 stars, and they only receive 1, 2 or 5 stars if we have a sufficient statistical basis upon which to assess them. As they receive more ratings, the fixed ratings will mean less and less.

Calculation of the number of stars
Finally, the ratings from various data sources are added up to form an overall rating. In order to do so, we must first convert them to a common currency. By recalculating all data sources to a common job satisfaction score, we can add up the ratings from the different sources.

The job satisfaction score is set to the nearest whole number of stars, which then becomes the overall rating score:

• A job satisfaction score of 0-1 equals 1 star
• A job satisfaction score of 1-2 equals 2 stars
• A job satisfaction score of 2-3 equals 3 stars
• A job satisfaction score of 3-4 equals 4 stars
• A job satisfaction score of 4-6 equals 5 stars

Questions about data sources and weighting
If you still have questions about how we calculate overall rating scores, you are welcome to write to us at evaluering@jobindex.dk.