General observation

of speech style similarities among presidents.

General analysis of potential correlations between style and topics.

General analysis of factors influencing styles and topics.

Layout

• ForceAtlas2
  
• Visual distance = linguistic style distance. It visually represents the distance and similarities between presidents and clusters effectively. Position nodes in a way that reflects their relative distances or similarities.
  

Node Size

• The size of nodes reflects the degree to which a president's style is connected to others.
• Larger nodes indicate a stronger influence on other presidents' speech styles.

Controlling Variables

We maintained a same layout (style similarity) and same node size (style influence) while manipulating colors (to understand the factors influencing speech style).

Nodes Files

• basic-information-presidents.csv (created by processing preexisting dataset): ID (names of presidents), Years in Office, number (president number), party.
• topic-probability.csv (created through topic modelling): ID (names of presidents), 7 topics.
• When importing two nodes file into Gephi, two nodes file can be merged based on same column 'ID.'

Edges Files

• edge_file.csv (created from Stylo analysis)
  
• Source (names of presidents)
  
• Target (names of presidents)
  
• Weight (linkage between two presidents)
  
• Type (undirected).
  

Analyzing General Trend

Speech styles change over time and presidents often share similarities with their contemporaries.

The gradual darkening of colors from one end to the other signifies the changing speech styles over time. It indicates how presidents' speech styles evolved chronologically. Darker green represent more recent periods, while lighter green represent earlier periods.

Analyzing General Trend

Various clusters exist within the early periods, suggesting a style variety in the early periods.

The purple cluster represents modern times (after the 1920s), while other clusters represent earlier periods. Various colors indicate different clusters of linguistic styles. The substantial gap between the purple cluster and others indicates significant style changes during this specific period.

Analyzing General Trend

The various topic clusters align with clusters of linguistic styles as well as with the timeline.

The gradient colors indicate topics, with darker red representing a higher probability of a specific topic, and lighter red indicating a lower probability. This intensity of color illustrates which presidents focus more on these topics.

Analyzing General Trend

Franklin Roosevelt stands out as the largest node, suggesting that he is the turning point for style changes.

At the boundary of the purple cluster (modern periods after 1920s), Franklin Roosevelt stands out as the largest node, suggesting that he is the turning point for style changes. Although other presidents like Warren Harding also contribute to these changes, their smaller node size suggests a relatively lesser influence compared to Roosevelt.

Franklin Roosevelt emerges as one of the central figure in the topic about war and peace, whose style had a significant influence on others

Most frequent words: president, peace, people, united, war, nations, american, time, freedom, country, hope, congress, day, program, vietnam, forces, south, military, defense, policy.

Analyzing General Trend

Alignment of Topics and Timelines

Andrew Jackson, the key figure during the second political era, along with Matin van Buren, are the emerges central figure in this topic.

Most frequent words: united, government, public, congress, country, citizens, power, war, powers, time, subject, treaty, laws, duties, peace, mexico. The topic cluster align with the second political era (1829-1854).

Historical Events:

• Mexican-American War: 1846-1848
  
• Bank War: 1830s
  

Analyzing General Trend

Alignment of Topics and Timelines

Analyzing General Trend

Alignment of Topics and Timelines

Abraham Lincoln is the key figure in this topic.

Most frequent words: constitution, people, president, government, congress, union, question, power, law, authority, time, principle, federal, war, territory, slavery, country, military, south, political, north, civil. The opic cluster align with the 1860s.

Historical Events:

• 1863: Lincoln issues the Emancipation Proclamation.
  
• 1863: Union wins the Battle of Gettysburg.
  
• 1865: Civil War ends.

Key figures in this topic are Ronald Reagan, Bill Clinton, George H. W. Bush, Barack Obama.

Most frequent words: people, america, government, tax, security, children. The topic cluster align with the 1970s-2000s.

Historical Events:

• Reaganomics: 1980s
  
• Cold War: 1945-1991
  
• North American Free Trade Agreement (NAFTA, 1994):
  
• Americans with Disabilities Act (ADA, 1990)
  
• Affordable Care Act (ACA, 2010)
  

Analyzing General Trend

Alignment of Topics and Timelines

Key figures in this topic are Donald Trump and Joe Biden.

Most frequent words: people, president, america, country, united, time, iraq, applause, nation, job, workers, law, love, afghanistan, china. Topic cluster align with the 2010s-2020s.

Historical Events:

• The U.S. War in Afghanistan: 1999-2021
  
• US-China relations: a significant topic in recent years due to trade disputes, economic competition, and geopolitical tensions.
  

Analyzing General Trend

Alignment of Topics and Timelines

Analyzing General Trend

Alignment of Topics and Timelines

Key figures in this topic are Benjamin Harrison and Grover Cleveland.

Most frequent words: united, government, congress, law, department, service, legislation, secretary, report, american, commission. Topic cluster align with the 1870s-1910s.

Historical Events:

• Reconstruction Era (1865-1877): Followed the American Civil War, the U.S. government focused on rebuilding and reintegrating the Southern states into the Union.
  
• Progressive Era (1890s-1920s): Characterized by social and political reforms, with increased government intervention and regulation.
  
• Foreign Affairs: e.g., Spanish-American War (1898).
  

Key figures in this topic are Theodore Roosevelt, Herbert Hoover, etc.

Most frequent words: government, business, american, national, people, country, public, action, federal, war, law, life, labor, conditions, service, and power. Topic cluster align with the 1900s-1930s.

Historical Events:

• Progressive Era (1890s-1920s): This period saw significant social and political reforms aimed at addressing social injustices, improving labor conditions, and regulating big businesses.
  
• World War I: 1914-1918
  
• The construction of the Panama Canal: 1903-1914
  

Analyzing General Trend

Alignment of Topics and Timelines

Analyzing General Trend

Minimal impact of political party affiliation on linguistic styles and topics.

Different colors represent different political parties of presidents. The distribution of political parties on the network does not align with the patterns observed in the timelines, and clusters of speech linguistic styles or topics. There is no clear relationship between the political party a president belonged to and the way they spoke or the subjects they addressed in their speeches. The network analysis did not reveal a strong correlation between the party affiliation and the identified patterns.

Analyzing General Trend

Linguistic style and topics in US presidential speeches have changed over time, as indicated by the color gradient representing chronological evolution of speech styles.

1920s-1930s is a turn point of changes of speech linguistic styles.

Topic clusters align with linguistic style clusters and the timeline, indicating that a shift in the linguistic styles and topics addressed in presidential speeches were influenced by historical events.

Franklin Roosevelt has had a significant influence on the evolution of speech styles.

Political party affiliation does not have a significant impact on linguistic styles and topics in presidential speeches.