UniPicker White Paper

Electronic draw is a drawing method that randomly selects winners using 'computer random numbers'. It generates random numbers within a specific range and assigns them to each entry, and then selects the winner who received the fastest random number or matches the randomly generated number.

A computer generates random numbers using various calculation logic, known as a 'random number generation algorithm'. This can be understood as a type of 'function' that produces an output value depending on the input value.
The computer's random number generation algorithm also requires input values to output random numbers.
To generate a large quantity of random numbers, previously generated random numbers are used as input values for the algorithm to generate the next set of random numbers. In other words, by passing an input value to the random number generation algorithm only once, we can repeatedly follow the procedure outlined above to generate a large number of random numbers.
The initial input value passed to the 'random number generation algorithm' is called the 'seed'.

All random numbers generated by the 'random number generation algorithm' are determined by the initially inputted 'seed', so the 'seed' can be considered as the factor that decides whether you win or not. If you input the same 'seed' and the same draw data into two different draws and use the same 'random number generation algorithm' to draw lots, the results of the two draws will be exactly the same.

Fair digital draw require transparent disclosure and explanation of how the 'seed' was determined, in addition to disclosing the 'seed' and 'random number generation algorithm' used for the draw.

UniPicker manages the 'seed' fairly according to the following procedure. ( storage period: up to 2 years )

1. UniPicker operates a 'seed server' and randomly generates a 'seed' through a disclosed 'seed generation algorithm' ( 'seed generation algorithm' is a type of 'random number algorithm' )
2. The user's 'seed request PC time' and 'seed request receiving server time' are converted to Unix time and added together, and then passed as input values to the 'seed generation algorithm' for the draw. This policy is to prevent UniPicker or the draw operator from unilaterally determining the important 'seed' that determines the winning result.
3. UniPicker publicly discloses the 'seed server' in real-time, so any UniPicker member can monitor the seed issuance status and can retrieve the seed info for previous draws using the 'seed request key'.

UniPicker selects winners using the following logic.

1. Obtains a 'seed' from the 'Seed Server'.
   The 'seed' is then used as input to the 'Random Number Generation Algorithm'.
2. Assign a random number to each entry.
3. Sort the entries based on the assigned random numbers.
4. The group drawing type also assigns a random number to the draw setting info.
   Group draw refers to the drawing of winners by group. For this type of draw, you need to input drawing setting info that determines the number of winners by group info(such as rank or prize, house room number).
   UniPicker assigns random numbers not only to applicants but also to draw setting info.
5. Sort the draw setting info based on the random numbers
6. The sorted entries are picked in order and assigned(win) to the sorted draw setting info.
   * When sorting the entry (or draw setting) info, it is sorted based on the random number assigned to each entry. If the seed is odd, it is sorted in ascending order, and if it is even, it is sorted in descending order. In the case where multiple entrants are assigned the same random number, the priority is given to the entrant who was registered first to prevent any biases towards certain entrants.

The random numbers used in the weighted winner selection process are generated using either the SHA-256 (Seed|N) method¹ or the xoshiro (Seed) method², excluding the seed generation process.

UniPicker applies the Weighted Win Range Draw Method as follows.

1. Shuffle the entries.

   Shuffle the entries. Shuffle the entry list using the Fisher–Yates shuffle algorithm³.
   The entries are arranged according to the shuffled order, and each entry is assigned a Win Range proportional to its weight.

2. Shuffle the draw info.

   Shuffle the draw info using the Fisher-Yates shuffle algorithm³.

3. Generate the 'Win Value'.

   (1) The 'Win Value' ranges from 1 to the 'Total Weight'.

   (2) Generate a random number within this range and use it as the 'Win Value'.

   Ex: If the 'Total Weight' is 600,
   the 'Win Value' ranges from 1 to 600.

4. Select the winner.

   Iterate through the entries in order. If the 'Win Value' falls within an entry's 'Win Range',
   that entry is selected as the winner.

5. Assign the winner to the draw info.

   Assign the selected winner to the shuffled draw info.
   Repeat the process from (3) to (6) until all draw info has been assigned.

6. Exclude the selected winner.

   Ex: Total Weight 600 → Winner Weight 160 → Next Win Value: 1 to 440

UniPicker applies the following Weighted Winner Selection Method based on Key values.

1. Assign a random number to each entry.

   Generate a random number (u) between 0 and 1 for each entry.

2. Generate a Key value for each entry.

   Calculate the Key value using the assigned random number (u) and the entry's weight (w).

   Entries with higher weights are more likely to generate smaller Key values. The winning priority is determined by the Key values in ascending order.
3. Sort the entries in ascending order of their Key values.
4. Assign a random order to the draw info.

   Shuffle the draw info using the Fisher-Yates shuffle algorithm¹.

5. Assign the entries sorted by Key value to the shuffled draw info in order.

UniPicker applies the following ball number seed draw logic.

1. Assign random number to each entry.

   * Assign first 10 digits(UniPicker random seed) after removing the decimal point.

2. Multiply the random number of the entry and the ball number.

   * The ball number drawn on-site is used publicly.

3. Entries are sorted based on the last 8 digits of the multiplied value.
4. The sorted entries are processed in order for winning.

   * When sorting the entry info, each entry is sorted based on the assigned winning random number. the input ball number is an 'odd number', the entries are sorted in ascending order. the input ball number is an 'even number', the entries are sorted in descending order.
   If multiple entrants have the same number, priority is given to the first registered entrant to avoid biases.

   * This draw does not randomly shuffle the draw setting info.
   This is a policy to determine the winner based on the sorting order of transparently disclosed entry numbers.

Fair digital draw must be tamper-proof and capable of proving that they have been conducted without tampering.
Tampering with a drawing refers to the act of intentionally manipulating the results to favor a particular entrant, or manipulating the fair results after the drawing has been conducted.

1. Draw Uniqueness Guarantee
   1. (1) Public Record Policy
      The policy of disclosing the history of the draw member is in place to prevent the repetition of the draw until the desired outcome is achieved.
   2. (2) Provides Draw Unique Code
      UniPicker generates a code that hasn't been used for the same draw name before to prevent member from repeatedly participating with multiple accounts
2. Methods To Prevent Tampering Of Draw Program
   1. (1) Releasing Seed Generation Algorithm Verification of Seed Value Generation
   2. (2) Real-time Disclosure of Seed Status Prevention of Seed Value Manipulation
   3. (3) Using Open-source Algorithm Verify the random numbers assigned to entries
   4. (4) Disclosure of Drawing Logic Verification of winner order per entry
   5. (5) Draw Screen Record Function Confirmation of various input data used in the draw
      - Draw PC Time
      - Entry Info
      - Draw Setting Info
      - Seed history
      - Draw Results
3. Prevent Invention Device
   1. (1) Draw Data File and of Draw Result file hash code storage
   2. (2) Original Data file checking system

      * A file hash code is a unique value calculated for a file using a specific hash algorithm.
      It changes if the file data is modified, making it useful for verifying the original file.

4. Verification Of Draw Results

   Digital draw using seeds can perfectly replay the drawing results. By inputting the seed value and original data used in the previous drawing to the UniPicker verification draw, the same draw results as the previous drawing can be confirmed. UniPicker can also be used to verify whether the seed value and data used in the previous draw are genuine. If a different seed value or manipulated input data is used for the actual draw, it will result in different draw results, and this can be considered a failure in verifying the draw results .

UniPicker is a reliable and fair draw software used by numerous public institutions, including courts and local governments. Using UniPicker can earn the trust of entries in the draw fairness, the most fair way to conduct a draw is through a 'public draw' using UniPicker. Notifying the entry of the UniPicker Public Record ID and draw date, and conducting a live YouTube broadcast or on-site public draw in accordance with the notified schedule is the best way to prevent complaints by disclosing the all draw process to the entries.