Where does smear collide?

In cytopathology and haematology, a smear is a thin film of cells (such as blood or exfoliated cells) spread across a slide, stained, and examined under the microscope to assess cell morphology. Mohan (2017), in Practical Pathology, describes peripheral blood smear preparation and examination. Here a smear is a cell film for diagnosis, not a clay layer along a fault or a statistical retransformation.[1]

Unit

One stained cell film on a slide.

Recovery means

Spread cells into a thin film on a slide, stain, and read the morphology.

Measured by

By light microscopy of the stained film.

In structural geology, shale smear is the layer of clay-rich material dragged along a fault plane as it slips, which can seal the fault against fluid flow across it. Aydin and Eyal (2002), in the AAPG Bulletin, anatomize a normal fault with shale smear and its implications for fault seal. Here smear is a clay membrane along a fault, not a cell film on a slide or a statistical correction.[2]

Unit

One shale-smear layer (its continuity and thickness along the fault).

Recovery means

Trace clay dragged along a fault and assess whether it is continuous.

Measured by

By shale-smear factor / clay-smear potential from throw and bed thickness.

In statistics, the smearing estimate is a nonparametric way to retransform predictions from a model fitted on a transformed scale (such as log) back to the original scale without assuming a particular error distribution. Duan (1983), in the Journal of the American Statistical Association, introduced the smearing estimate. Here smear names a retransformation correction, not a cell film or a fault-sealing clay layer.[3]

Unit

One smearing factor (the averaged retransformed residual).

Recovery means

When back-transforming a log-scale fit, apply the averaged residual correction.

Measured by

Computed from the model residuals on the transformed scale.