The candidates' time allowance was equal and given the fact that both candidates used approximately the same number of words, it can be concluded that the global cadence of speech is similar.

Although I am not surprised that ratio of the total number of used words is similar (Obama delivered 7,529 words, 7% more than McCain's 7,043), the fact that the total number of unique words was nearly identical for both candidates (1,376 vs 1,380) was a shock. Though both Obama and McCain can be considered articulate, Obama presents as verbally sharper than McCain and his delivery has a greater nimbleness to it, which is reflected in his slightly higher volume of word delivery. During his unscripted deliveries, Obama's manner hints at a significant command of the English language and suggests that his verbal abilities are not stretched. For this reason, I was expecting his unique word count to be higher.

The fact that the unique word count is identical suggests a high degree of rehearsal and preparation. It may well be that both candidates spent significant amount of time being coached to effect the best delivery that would reach the most number of people. It may also be that through the process of political selection, both candidates epitomize an archetype of spoken word delivery.

It also came as a surprise that the total number of unique words used by both candidates was only 2,115. Initially, I felt this to be low — surely the matters of state require more than two thousand words. For both candidates, I suspect a significant amount of coaching towards conformity to the average American's comprehension.

a c b d

a :: total number of words b :: proportion of words in the debate c :: unique words in (a) d :: (c) relative to (a) bar :: proportion of (a-c):c

Obama's absolute stop word count is higher than McCains (4,263 vs 3,922) but Obama's total word count is also higher. When the total number of words is considered, Obama and McCain stop word delivery is similar, at 56.6% and 55.7%, respectively.

Stop word counts do not reveal significant difference between the two candidates.

a c b d

a :: total number of words, for a given category (all, stop, non-stop) b :: (a) relative to words in the debate if category=all, otherwise relative to words by the candidate c :: number of unique words with set (a) d :: (c) relative to (a) bar :: proportion of (a-c):c

Both Obama and McCain average word frequency is similar, at 2.63 and 2.51, respectively. 50% of Obama's speech is composed of words he used 4 times or fewer — identical to McCain. 90% of Obama's (McCain's) speech was composed of words used 24 (21) times, or fewer, with the difference not being significant.

a b c

a :: average word frequency b :: largest word frequency in 50% of content c :: largest word frequency in 90% of content bar :: proportion of a:b:c

Obama's sentences are 9% longer (17.4 vs 15.9) when all words are considered and 8% longer (7.7 vs 7.1) when stop words are removed. This sentence size difference is commensurate with the difference in total word delivery, suggesting that the total number of sentences by the candidates was similar. In fact, Obama delivered 449 sentences and McCain 460 (not shown).

a b c

a :: average sentence size b :: largest sentence size for 50% of content c :: largest sentence size for 90% of content bar :: proportion of a:b:c

The composition of the candidates' speech by part of speech is remarkably similar. The relative breakdown of nouns, verbs, adjectives and adverbs for Obama is 53:25:15:7 and 54:26:14:5 for McCain. I am more than mildly surprised at such an incredible uniformity in the speech of the candidates. The ratio of noun:verb:adjective:adverb reduces to about 8:4:2:1.

Within each POS category, the number of unique words is nearly identical for both candidates, with Obama (McCain) having 39% (41%), 46% (45%), 45% (45%) and 34% (39%) of their nouns, verbs, adjectives and adverbs unique. The largest difference is in the use of adverbs, with McCain having 39.2% of all his adverbs unique, whereas Obama's adverbs have a unique component of 34.3%.

Note that Obama uses adverbs more than McCain (6.8% vs 5.5%) — his speech included 213 adverbs (73 unique) whereas McCain used 166 adverbs (65 unique).

a c b d

a :: total number of words for a given POS (all, noun, verb, adjective, adverb) b :: (a) relative to all words by candidate c :: unique words in (a) d :: (c) relative to (a) bar :: proportion of (a-c):c

This table hints at a significant difference in verb and adverb use.

As indicated in the previous table, McCain used fewer total adverbs than Obama (166 vs 213), but his unique adverb fraction was higher (39.2% vs 34.3%). It looks like Obama really likes adverbs, and really likes repeating them too. Obama's average adverb frequency was 2.92, compared to McCain's 2.55. Moreover, 90% of Obama's adverbs were used with a frequency of 36 times or less, whereas 90% of McCain's adverbs were used with a frequency of 13 or less.

Obama, however, is significantly less repetitive with verbs, with 90% of his verbs used 16 times or less, compared to 90% of McCain's verbs which were used 25 times or less. Thus, although the candidates' total and unique verb count was similar (see previous table), Obama's distribution in verb frequency was skewed towards less repetition.

a b c

a :: average word frequency b :: largest word frequency in 50% of content c :: largest word frequency in 90% of content bar :: proportion of a:b:c

Obama had consistenly more total and unique pairings than McCain. This is largely due to the fact that Obama had longer sentences (7.7 non-stop words) than McCain (7.1 non-stop words).

The largest pairing difference was seen in the adverb/adverb category, where obama had nearly twice as many pairings (84 vs 49) than McCain. In other POS pairing categories, McCain' numbers were consistently 70-85% that of Obama's.

When unique pairings are compared, the candidates fare more equally, both having 80-90% of pairings unique. The only exception was adverb/adverb pairs, with Obama's unique component being 78.6% compared to McCain's 91.8% (Obama repeats adverbs).

a c b d

a :: total number of pairs, for a given category (e.g. verb/noun) b :: (a) relative to all pairs c :: number of unique pairs within set (a) d :: (c) relative to (a) bar :: proportion of (a-c):c

a c   d b e

a :: total number of pairs for Barack Obama b :: relative unique pairs for Barack Obama c :: total pairs for John McCain d :: (c) relative to (a) (i.e. John McCain relative to Barack Obama) e :: relative unique pairs for John McCain bars :: values of (a), (b), (c) and (e)

Previous tables indicated that speech delivery for the candidates is incredibly uniform. This table shows each candidate's contribution to unique words in the debate.

There were a total of 1,034 unique nouns used in the debate, with 371 (35.9%) used only by Obama, 389 (37.6%) by McCain and 274 (26.5%) by both. In fact, for all parts of speech the candidates had more words that they used exclusively than those they shared with each other. Even for adverbs, which is the least populated group of words, the candidates shared only 30 adverbs, and had 43 (Obama) and 35 (McCain) that they used exclusively.

It is not surprising that the proportion of unique words was larger for the set of exclusive words than for the set of shared words. Typically, the unique proportion within exclusive words were around (60-70%) but much lower at 12-15% for shared words. This indicates that the words spoken by both candidates were repeated much more frequently.

a d b e c f

a :: total number of words unique to a candidate, for a given POS group b :: (a) relative to all unique words to the candidate c :: (a) relative to all words d :: unique words in (a) e :: (d) relative to (a) f :: (d) relative to all unique words bar1 :: normalized ratio of (a-d):d bar2 :: absolute ratio of (a-d):d for all POS groups (first column) or POS group (other columns)

Obama has +4.0% more noun phrases than McCain (855 vs 851). The difference between the fraction of unique noun phrases, however, is smaller between Obama and McCain, whose noun phrase uniqueness is 84.3% and 83.3%. Relatively to the number of noun phrases, the number of top-level phrases is similar between them, as is the top-level uniqueness ratio.

a c b d

a :: number of noun phrases b :: (a) relative to number of all noun phrases c :: number of unique phrases d :: (c) relative to (a) bar :: normalized ratio of (a-c):c

The ratios here are very similar. Extremely similar, in fact, with the exception of the ratio of unique noun phrases to unique nouns, which is 1.16 for Obama and 1.07 for McCain. The interpretation is that Obama constructed a greater diversity of distinct concepts with his nouns.

a b	a :: ratio of the number of noun phrases to number of nouns b :: ratio of the number of unique noun phrases to number of unique nouns bar :: ratio of a:b

Values are nearly identical for both candidates. Both repeat noun phrases an average of 1.19-1.20 times, and have 2.73-2.76 words per noun phrase.

a b c

a :: average b :: 50% weighted cumulative value c :: 90% weighted cumulative value bar1 :: normalized ratio of a:b:c

Obama's Windbag Index is +14.7% when compared to McCain's, at 422 vs 368.

The index is a compound score, with contributions from nine terms. Individually, Obama does better at the verb, adjective and noun phrase components. McCain, on the other hand, has superior contributions from word counts, nouns and adverbs.

The tag clouds for all words used by each candidate powerfully show the difference in word frequency distribution between Obama and McCain. In a few tables, I indicated the average and 50%/90% weighted cumulative values for frequencies, but did not explicity show a distribution. Well, these tag clouds show that.

McCain's cloud has a significantly more large words, when compared to Obama's, indicating that McCain repeated a larger subset of words throughout the debate. For example, McCain's use of the word "nuclear" was nearly as frequent as his use of the word "Obama". On the other hand, Obama's use of "nuclear" was smaller than his use of the word "McCain".

It is also interesting to see that Obama very frequently used "John", calling his opponent by his first name, whereas McCain never used Obama's first name, Barack.

The tag cloud composed of words used exclusively by McCain' indicates a high degree of relative repetition of a small subset of the words. The center of McCain's tag cloud is bloated with large text, indicating high relative usage of words like "afraid", "serious", "fragile", and "badly". Remember, these are words unique to McCain — Obama did not use these words.

Obama's tag cloud shows relatively less repetition among the words used only by Obama. In general, the words used by Obama that were not used by McCain are more uniformly distributed in frequency. It is surprising words like "recognize", "strategic", "solve", "invest", and "agree" are unique to Obama (they were not used by McCain).

Not surprisingly, the candidates' most frequent noun was Obama (for McCain) and John (for Obama). As I mentioned previously, it is curious to find that McCain never refered to Obama by his first name, Barack.

The cloud of green words around the central core of the tag cloud indicates that nouns unique to Obama appeared at a higher relative frequency than McCain.

Some interesting nouns for Obama are "alternative", "fundamentals", "medicare", and "diplomacy". On the other hand, words like "restraint", "failure", "corruption" and "maverick" are unique to McCain.

The top verb unique to McCain was "control", closely followed by "fought" and "succeed", followed by verbs like "defeat", "win", and "legitimize". For Obama, the top unique verb was "getting", followed by "invest", "funded", "recognize", "agree" and "rebuild", but those were of relatively lower frequencies than for words at the same rank in McCain's list. McCain repeats strong verbs.

If the verbs are an indication of action planned for and supported by the candidates, then McCain is someone who wishes to "legitimize" and "succeed [at] control", whereas Obama is more conciliatory and positive with "invest", "focused", "solve" and "recognize".

McCain's exclusive use of "afraid", "serious" and "fragile" are interesting and hint at fear mongering.

Adverbs are the least frequent of the four parts of speech, so the tag cloud here is less complex. Both candidates use strong and certain action modifiers like "completely" (McCain) and "absolutely" (Obama). As for other parts of speech, McCain had high relatively frequency of terms unique to him, and this is evident by a more large blue words in this tag cloud.

It is interesting to see Obama exclusively use words like "responsibly" and "structurally".

When all parts of speech are combined into one tag cloud, Obama's unique words swamp out those of McCain', suggesting that when parts of speech are combined, Obama repeated terms exclusive to him more frequently.

The major contributors to Obama's word pair tag clouds are open-ended word pairs such as "last several" (adjective/adjective), "correct just" (adjective/adverb), "mccain senator" (noun/noun). A couple of concepts such as "al qaeda" (qaeda was tagged as a verb by the Brill tagger), "north korea" were prominent, but these are proper nouns and reflect the topic under discussion.

Obama touched on many concepts, as indicated by the relatively flat distribution of sizes in the noun/noun tag cloud. Some of these were "care health", "biodiesel energy", "oil world", "energy wind". Some curious ones were "john spending", "crisis day", "afghanistan iraq", "deal russia". These should be contrasted to noun/noun pairs for McCain (below), which focused on threats and the military.

McCain' pair tag clouds have significantly different morphology than those of Obama. Primarily, due to McCain' repetitive use of certain words, the tag clouds are overwhelmed with these frequent (therefore large) pairs.

His adjective/noun tag clouds has an apocalyptic theme: "nuclear threat", "important thing", "long way", and (this is fascinating) "old russian" and "next states".

The noun/noun tag cloud size distribution is relatively flat, like that of Obama, and indicates topics such as "threat weapons", "business tax", "ahmadinejad extermination" and "aggression georgia". The majority of McCain's noun/noun concepts were threat- and military-related (contrast this to Obama, who was focused more on energy and economy). Environment? What environment?