Calculating the nearest political party
Volebný kompas shows the overlap between the parties’ positions and the users preferences. In order to simplify the interpretation of the results, the latter are expressed in terms of a percentage of overlap. 0% indicates that a political party and a user’s preferences do not overlap at all, 100% indicates that they completely overlap.
Technically, for calculating the overlap, we use the so called “Manhattan (or „city-block“) distance”, which expresses how close the two respective points are one from another in an n-dimensional space.
At the heart of Volebný kompas lies a series of political or policy-related short arguments – the statements – on which it is possible to take a position. For example, Volebný kompas offers to users to take a position regarding the statement "People who earn higher wages should have a higher income tax rate ". Users can choose from the following answer categories: 'Completely agree', 'Tend to agree', 'Neutral', 'Tend to disagree' and 'Completely disagree'. Volebný kompas also allows users to choose the option 'No opinion'.  
For calculating the overlap, we first translated the answers given by the users into numbers, using the following key:

Completely disagree = 0
Tend to disagree = 25
Neutral = 50
Tend to agree = 75
Completely agree = 100

The same values were given to the positions taken up by the parties. We then started off to calculate the distance between the positions of each user and political party on every statement, and then the average matching percentage across all the 39 statements.

Calculation of Uni-dimensions
Every statement can have some effect on one uni-dimensions, or two. The resultant effect is defined with values: 1 (positive polarity), -1 (negative polarity). Positive polarity means that only positive answers (75-100) increase the value and negative polarity means that only negative answers (0-25) increase the resulting value. Statements with polarity 0 are not included in a uni-dimension calculation.
The resulting value regarding all answered questions for a political party or user can vary from 0 to 100, where 100 means total agreement.
For example, if five statements pertain to the uni-dimension “Environment”, the first one has a polarity value of -1 for the dimension and the remaining four have a polarity of 1, the user has to answer “Completely disagree” to the first one and “Completely agree” to the remaining four statements to get maximum score on the dimension (i.e., be placed on the right end of the economic growth/environmental protection continuum).
The following list documents how the statements were grouped in order to lead to the scores for the five uni-dimensions. The * asterisk indicates those statements (two in total) that have an effect on two diferent uni-dimensions.

MULTILEVEL GOVERNANCE: MORE POWER TO THE REGIONAL LEVEL (-) vs. MORE POWER TO THE CENTRAL LEVEL (+)
For a more homogenous regional development, poorer regions in Slovakia should be helped out at the expense of richer ones (-)
The powers of the regions and localities should be strengthened at the expense of the central government (-)
* Teachers' salaries in the regions should be different according to the average salary in a given region (-)

FORM OF GOVERNMENT: LIBERAL DEMOCRACY (-) vs. AUTHORITARIAN REGIME (+)
Liberalism (a set of views trying to assert the freedom and rights of the individual and the idea of progress) poses a threat to Slovakia (+)
Slovakia needs a leader similar to Viktor Orban in Hungary (+)
NGO funding should be subject to greater state control (+)

ENVIRONMENT: MORE EMPHASIS ON ECONOMIC GROWTH (-) vs. MORE EMPHASIS ON ENCIRONMENTAL PROTECTION (+)
Banning the production of new cars with internal combustion engines after 2035 is the right step (+)
Tackling climate change has a higher priority over achieving higher economic growth (+)
Renewable sources of energy (e.g. solar or wind energy) should be supported even if this means higher energy costs (+)

EUROPEAN UNION: MORE NATIONAL AUTONOMY (-) vs. MORE EUROPEAN INTEGRATION (+)
Membership of the European Union is more beneficial than harmful to Slovakia (+)
The European Union should  punish Member States that violate the commonly agreed rules (+)
The European Union should abandon the principle of unanimity of member states in making foreign policy decisions (+)

FOREIGN POLICY: ISOLATIONISM (-) vs. INTERNATIONAL ENGAGEMENT (+)
Membership of NATO is more beneficial than harmful to Slovakia (+)
Slovakia should stop providing military aid to Ukraine (-)
Russia should bear financial consequences for unleashing war on Ukraine (+)
Food self-sufficiency should be a priority for Slovakia (-)
Russia is the aggressor in the war in Ukraine (+)
It is unreasonable to demand that Slovakia spend 2% of its GDP on defense (-)

Political Landscape
The political landscape is based on similar assumptions as the uni-dimensions, but goes a step further. Namely, while the uni-dimensions represent the political spectrum in five separate dimensions, the political landscape further reduces the complexity of politics and offers only two major dimensions: an economic and a cultural one.
Both of these dimensions range from zero to one hundred. In order to determine the position candidates and users in this two-dimensional space, we need to calculate their respective coordinates on the X and Y axes.
The initial position of a political party on an axis is 50% (neutral). Its position on an axis is calculated over all statements using the same formula as the uni-dimensions. Statements with polarity 0 are not included in a landscape dimension calculation. 1 shifts the position on an axis to the positive, and -1 to the negative side.
The political landscape representation is based on the assumption that, in most political systems, citizens’ and political parties’ opinions on individual issues can be aggregated to a limited number of issue dimensions. In the graphical representation offered to the user, the position of parties (and of the user) on each axis is the average of all positions across issues pertaining to each dimension.
The computation of such averages, on each of the two axes, depends on a priori considerations, both in terms of which dimension an issue belongs to, and which side of the dimension a specific issue positions belongs to.
According to a structure of attitudes of the Slovak political space, we have assigned 16 (out of the 39 statements in total) to each of the two dimensions according to the following table:

ECONOMIC DIMENSION: LEFT (-) vs. RIGHT (+)
* Teachers' salaries in the regions should be different according to the average salary in a given region (-)
Real estate tax should be increased to lower labor taxes (-)
People who earn higher wages should have a higher income tax rate (-)
The retirement age should rise as life expectancy rises (+)
In the health care system, more emphasis should be placed on the personal responsibility of the individual (+)
Banks and big corporations should be taxed more heavily (-)
Health insurance companies should not generate profit (-)
The state should play an active role in regulating food prices (-)
During energy crises, the state must cover all extra household energy costs (-)
The state should provide targeted help to people who are struggling to repay their mortgages (-)
* Reducing the gender pay gap in Slovakia requires state intervention (-)

CULTURAL DIMENSION: LIBERAL (-) vs. CONSERVATIVE (+)
* Reducing the gender pay gap in Slovakia requires state intervention (-)
Same-sex partnerships should be legalised (-)
The personal use of marihuana should be legalized (-)
Abortion rights in Slovakia should be restricted (+)
Slovakia should make it easier to bring in foreign workers (-)
The State and the Church should remain separated (-)
Both the position of the user and the position of candidates are presented to the viewer as points in a two-dimensional space. Please note that this visualisation does not influence the “Party match” result. Also, five statements were included that do not pertain to any of the two dimensions of the political landscape, or any of the five dimensions of the uni-dimensions; therefore, these contribute to calculate the party matching percentage but do not influence the visualization tools.

Additional statements
Six additional statements have been included. These statements do not have a corresponding dimension, and therefore do not have poles and polarity as well. As such, they contribute to the calculation of the overall matching between user and parties, but do not impact on the uni-dimensions or the bi-dimensional landscape. These are:
Support mechanisms for refugees from Ukraine should be more limited
Section 363 of the Code of Criminal Procedure should be significantly restricted (the section allows the Attorney General to overturn a legally binding decision)
Plagiarists should not hold public office
Investigations and prosecutions of former high-ranking officials launched after 2020 are important for societal renewal
The state should take more active efforts to improve the quality of life of Slovakia's Roma popuation
The government should increase support for cultural and educational activities in the Hungarian language