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Debt Analysts' Views of Debt-Equity Conflicts of Interest

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TABLE 1<br />

Accuracy <strong>of</strong> Naïve Bayes classification algorithm<br />

This table presents out-<strong>of</strong>-sample and within-sample accuracies <strong>of</strong> the Naive Bayes classification by comparing the<br />

algorithmic classifications with the manual classifications. To calculate the Naive Bayes out-<strong>of</strong>-sample accuracy,<br />

presented in Panel A, we randomly partition the manually coded training dataset into two equally sized parts. One<br />

part is used to estimate the Naive Bayes model, while the other is used to test the accuracy <strong>of</strong> the model’s predicted<br />

classification. For an example, refer to the first row <strong>of</strong> Panel A. Out <strong>of</strong> a total <strong>of</strong> 262 manually classified negative<br />

text extractions, 124 were classified correctly as negative by the s<strong>of</strong>tware — an accuracy rate <strong>of</strong> 47.3%. To evaluate<br />

the Naive Bayes within-sample accuracy, we use the entire manually coded training dataset to develop the Naive<br />

Bayes model, and then compare the model-predicted classifications with the manual classifications. For an example,<br />

refer to the first row <strong>of</strong> Panel B. Out <strong>of</strong> a total <strong>of</strong> 524 manually classified negative text extractions, 340 were<br />

classified correctly as negative by the Naive Bayes model — an accuracy rate <strong>of</strong> 64.9%.<br />

Classified by Algorithm Manually Accurately<br />

Negative Neutral Positive Classified classified<br />

Panel A: Naïve Bayes algorithm out-<strong>of</strong>-sample accuracy<br />

Negative 124 104 34 262 47.3%<br />

Neutral 284 1,707 240 2,231 76.5%<br />

Positive 71 256 146 473 30.9%<br />

Total 479 2,067 420 2,966 66.7%<br />

Panel B: Naïve Bayes algorithm in-sample accuracy<br />

Negative 340 144 40 524 64.9%<br />

Neutral 594 3,305 562 4,461 74.1%<br />

Positive 110 344 494 948 52.1%<br />

Total 1,044 3,793 1,096 5,933 69.8%<br />

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