How to use

DB

Scores DB

• Scores DB records examinees' names, scores, and subjects line by line
  • Subjects are relation and linked to the Subjects DB

Subjects DB

• In addition to displaying histograms, the Subject DB allows you to select colors and maximum scores
  • The histogram outputs a histogram of the Score DB scores related with the subject.
    • For a detailed explanation of this function → Explanation of source code
  • Colors can be specified for each line, so you can change the color for each subject.
  • Changing the maximum value is reflected in the histogram scale value

Histogram Settings DB

• Histogram Settings DB allows you to set values that are common to all histograms

  • Bar Width

    • If the width of the bar is too small or too large, the graph will be difficult to read.

      • Good：Bar Width=10

        

      • Bad：Bar Width=25

        

  • Max Bar Length

    • This value can be adjusted in case the graph is cut off depending on the card size or device used for the gallery view.

      • Good：Max Bar Length=65

        

      • Bad：Max Bar Length=150

        

How to read the histogram

Ticks

• Each tick value represents values greater than or equal to [tick value] and less than [tick value + width of the histogram bar].
  • For example, if the width of the histogram bar is 10, a tick value of "20" represents values greater than or equal to 20 and less than 30.
• The length of the bar to the right of the tick value represents the number of data points that fall within that range.

Mean

• The black line displayed on the graph represents the mean value.

  • Note: Due to limitations in graphical representation, the line may not be precisely plotted on the exact value.
  • In the left example, the mean value is 57.4, but the line representing the mean value is plotted just above 55.

• Due to limitations in graph representation, if the line representing the mean value coincides with the same bar as the standard deviation line, the line's color may not be black; it may be colored.

  • Example:

    

• In such cases, you can distinguish the mean value line because it slightly protrudes from the bar.

• Additionally, if the mean value and standard deviation lines are very close, it's recommended to reduce the width of the histogram bars in the graph settings.

Standard Deviation

• The colored lines displayed on the graph represent the lower and upper limits of the standard deviation.

  • Note: Due to limitations in graphical representation, the lines may not be precisely plotted on the exact values.

• Even if there are no bars directly above the tick values representing the lower or upper limits of the standard deviation, short lines are displayed on the tick values in the graph.

  • Example:

    

• What is Standard Deviation:

  • It represents the spread or dispersion of data (a concept similar to variance).
  • While a detailed explanation is omitted here, it's worth noting that between the lower and upper limits of the standard deviation, approximately 68% of the data points are contained.

Explanation of source code

• Source Code

Explanation of source code