> ## Documentation Index
> Fetch the complete documentation index at: https://instance.bio/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# specificity_scores

Summarized specificity scores assessing candidate selectivity across target and off-target antigens. Specificity scores compare the binding signal of a candidate against its intended target antigen to the signal observed against off-target antigens at equivalent concentrations. Replicate measurements are averaged across samples, and each tested concentration is pivoted into its own column.

**Grain:** one row per `(candidate_library_id, sino_catalog_id, variant_id)`.

### Fixed columns

| Column | Type | Description |
| :- | :- | :- |
| `candidate_id` | `string` | Identifies this candidate across the dataset. Two candidates with identical sequences share the same `candidate_id`. |
| `candidate_library_id` | `string` | Identifies the pooled candidate library that was expressed and tested. |
| `candidate_name` | `string` | The customer-provided name for this candidate. |
| `candidate_sequence` | `string` | The customer-provided sequence for this candidate. |
| `variant_id` | `string` | Identifies the specific sequence variant observed for this candidate. Equals `candidate_id` when the observed sequence matches the candidate sequence exactly. |
| `variant_sequence` | `string` | The observed sequence variant after sequencing. |
| `sino_catalog_id` | `string` | Identifies the antigen using its Sino Biological catalog number. |
| `antigen_gene_name` | `string` | Gene name of the antigen. |
| `antigen_sequence` | `string` | Amino acid sequence of the antigen. |
| `is_expressed` | `boolean` | Indicates whether this candidate was expressed in at least one sample. |

### Dynamic concentration columns

For each antigen concentration tested, the table includes a `log_specificity_score_{conc}nM` column and a matching `log_specificity_score_{conc}nM_std` column. The standard workflow uses 5, 50, and 500 nM.

| Column | Type | Description |
| :- | :- | :- |
| `log_specificity_score_5nM` | `float` | Mean log specificity score at 5 nM, averaged across replicates. |
| `log_specificity_score_5nM_std` | `float` | Standard error of the mean log specificity score at 5 nM across replicates. |
| `log_specificity_score_50nM` | `float` | Mean log specificity score at 50 nM, averaged across replicates. |
| `log_specificity_score_50nM_std` | `float` | Standard error of the mean log specificity score at 50 nM across replicates. |
| `log_specificity_score_500nM` | `float` | Mean log specificity score at 500 nM, averaged across replicates. |
| `log_specificity_score_500nM_std` | `float` | Standard error of the mean log specificity score at 500 nM across replicates. |

## replicate\_specificity\_scores

**File:** `replicate-specificity-scores-YYYYMMDD.parquet`

Sample-level specificity measurements across individual replicate samples and antigen concentrations. Use this table to inspect variation in selectivity between replicates and verify that candidate binding is specific to the intended target rather than cross-reactive with off-targets.

**Grain:** one row per `(expression_sample_id, binding_sample_id, variant_id)`.

| Column | Type | Description |
| :- | :- | :- |
| `candidate_id` | `string` | Identifies this candidate across the dataset. Two candidates with identical sequences share the same `candidate_id`. |
| `candidate_library_id` | `string` | Identifies the pooled candidate library that was expressed and tested. |
| `candidate_name` | `string` | The customer-provided name for this candidate. |
| `candidate_sequence` | `string` | The customer-provided sequence for this candidate. |
| `variant_id` | `string` | Identifies the specific sequence variant observed for this candidate. Equals `candidate_id` when the observed sequence matches the candidate sequence exactly. |
| `variant_sequence` | `string` | The observed sequence variant after sequencing. |
| `binding_sample_id` | `string` | Identifies the binding sample this measurement is based on, matching <Tooltip tip="Uniquely identifies a physical sample in the run. Other tables reference this value to indicate which sample a record came from.">*sample\_id*</Tooltip> in `dim_samples`. |
| `expression_sample_id` | `string` | Identifies the expression sample this measurement is based on, matching <Tooltip tip="Uniquely identifies a physical sample in the run. Other tables reference this value to indicate which sample a record came from.">*sample\_id*</Tooltip> in `dim_samples`. |
| `sino_catalog_id` | `string` | Identifies the antigen using its Sino Biological catalog number. |
| `antigen_concentration_nM` | `float` | Concentration of the antigen used for this measurement, in nanomolar (nM). |
| `antigen_gene_name` | `string` | Gene name of the antigen. |
| `antigen_sequence` | `string` | Amino acid sequence of the antigen. |
| `log_specificity_score` | `float` | Specificity score for this candidate in this sample at this concentration. Empty when Unique Molecular Identifier (UMI) counts do not meet quality thresholds. |
| `is_expressed` | `boolean` | Indicates whether this candidate was expressed in this sample. |


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.