Fishery View

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Fishery View
Improvement of Time Series Line Chart
Visualization of Fishery Data

• Project Team
• Ying Zhang, Lan Wu

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Fishery View

• Background
• The Fishery Department at UBC uses a tool called
  Ecopath to perform the analysis on the
  relationship of marine species in a food network
  and impact of humans fishing strategy on them.
• Ecopath uses a line chart system to draw the
  trends of all fish populations.
• The line chart is as the following

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Can anyone see problems with this graph?
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Problems

• Currently fish groups are represented by
  different colors of lines on the graph.
• However, due to the number of lines drawn on the
  screen, the chart suffers from an overload of
  visual information because of cluttering and
  overlapping.

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Proposed Solution 1

• Line Layering with Brushing through the Names of
  Fish Species
• The diet matrix describes the relationship of
  eating and being eaten (related and unrelated).
• By moving the mouse onto the top of a specific
  fish species , all the lines of its related fish
  species will be highlighted based on the diet
  matrix using a multiple color scheme. Any other
  lines of unrelated fish species will be put in
  the background in gray color.

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Proposed Solution 2

• Difference Graph
• This is to present the change of all kinds of
  fish population before and after a fishing
  strategy is applied. By only plotting the
  difference on the graph, the impact of fishing
  strategy on fish population will be clearly
  shown.

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Proposed Solution 3

• Line Clustering.
• We first sample M time points along the time
  series and record the population of each of the N
  fish species at that time point.
• With the matrix describing the fish population on
  the M time points provided, we calculate the
  sum-of-square-difference between each two of
  these N fish populations. With these data, we can
  construct the 'clustering matrix'.
• By searching in the 'clustering matrix', we can
  find the most similar fish species based on
  sum-of-square-difference, and then cluster them
  into one group.

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Proposed Solution 4

• Line Chart Zooming
• For the current line charts, all the lines drawn
  overlap with each other seriously.
• Zooming can enlarge a specific area of the line
  chart to a certain scale, so that the difference
  among the lines can be easily viewed.