Autocorrelation averages products across all shifted pairs

Evidence

Autocorrelation is not about a single pair of numbers—one entry and its partner straight across in the next column. Rather, if the second column has been displaced down by k places, the correlation c(k) of a list is computed as the average of all such products of the pairs across from each other, one from each list. — Eric J. Heller, Why You Hear What You Hear- An…, 389

Categorization

• DEFINE: Defines autocorrelation precisely: average of products across all pairs formed by a k-place shift.
• corroborated: 2 independent passages support this claim — Eric J. Heller, Why You Hear What You Hear- An…, 389
• XREF: connects to: Temperature autocorrelation reveals weather’s daily and seasonal periodicities.; Autocorrelation measures periodic self-similarity in a signal across time delays. — Eric J. Heller, Why You Hear What You Hear- An…, 369; The power spectrum is the Fourier cosine transform of the autocorrelation — Eric J. Heller, Why You Hear What You Hear- An…, 410 (+1 more)

Broader Connections

• Autocorrelation measures periodic self-similarity in a signal across time delays. #expands (0.95) — Eric J. Heller, Why You Hear What You Hear- An…, 369
• The power spectrum is the Fourier cosine transform of the autocorrelation #qualifies (0.80) — Eric J. Heller, Why You Hear What You Hear- An…, 410
• A signal’s autocorrelation is a cosine sum over its sinusoidal partials. #expands (0.80)