*iotarelr* provides routines and tools for assessing the
quality of content analysis on the basis of the Iota Reliability
Concept. The concept is inspired by item response theory and can be
applied to any kind of content analysis which uses a standardized coding
scheme and discrete categories. It is also applicable for content
analysis conducted by artificial intelligence. The package provides
reliability measures for the complete scale as well as for every single
category. Analysis of subgroup-invariance and error corrections are
implemented. This information can support the development process of a
coding scheme and allows a detailed inspection of the quality of the
generated data.

The tools are able to provide answers to the following questions:

- How reliable is the scale of a coding scheme?
- How reliable is a single category within a scale?
- Does the coding scheme work similarly for different groups of materials or different groups of people?
- How do coding errors bias the generated data?
- How can the generated data be corrected for errors?

A brief introduction on how to use the package can be found via Get started. Articles describing how to conduct advanced analysis can be found via Articles.

You can install the package from CRAN with:

`install.packages("iotarelr")`

You can install the development version of *iotarelr* from GitHub with:

```
# install.packages("devtools")
::install_github("FBerding/iotarelr") devtools
```

*iotarelr* calculates the following components of the *Iota
Reliability Concept*.

**On the level of every single category:**

Matrix containing the probabilities to assign a coding unit truly belonging to category i to category j.*Assignment Error Matrix:*Probability to assign a coding unit of category i to category i.*Alpha Reliability:*Probability to assign a coding unit of category j to category i.*Beta Reliability:**Iota Reliability:*Value ranging between 0 and 1, reflecting how well the generated data of category i really reflects category i.*Iota:*Value describing how many coding units are missing in the data for category i.*Iota Error I:*Value describing how many coding units from*Iota Error II:**other*categories are part of the data for category i.

**On the scale level:**

Measure for describing the reliability of a scale. Zero indicates the absence of reliability. One indicates perfect reliability.*Iota Index:*Transformation of the original*Dynamic Iota Index:**Iota Index*to account for the uncertainty of reliability estimation. Zero indicates the absence of reliability. One indicates perfect reliability.

The parameter estimation of the components makes use of Maximum Likelihood Estimation (Expectation Maximization Algorithm), which comprises an additional conditioning stage. The following figure shows the extent to which the estimated parameters correspond to their true values based on a simulation study (Berding & Pargmann 2022).

In general, the parameter (Primary Parameters, Alpha and Beta
Reliability) estimates do not deviate from their true values by more
than 5 percentage points (see median in the figure). In most cases,
*Iota Index* deviates no more than .043 from its true value. The
estimates are more accurate, the greater the sample size and the more
raters are involved in coding. Furthermore, the estimates are more
accurate for higher values of true reliability.

Please note that the high deviation for Beta Reliability under the condition of very high reliability results from rare cases with perfect Alpha Reliability. For more details please refer to Berding & Pargmann (2022).

Studies investigated the power of the Iota Concept for predicting the
quality of data generated by content analysis and compared the Iota
measures with other existing measures of inter-coder reliability. The
figure shows *R²* for both nominal and ordinal data.

For the case of nominal data, the *Dynamic Iota Index*
performs similarly or even better to *Krippendorff’s Alpha* when
predicting the deviation between the estimated sample association and
the true sample association. Alike applies for estimating the risk of
Type I errors and the chance for correctly classifying the effect size
into categories proposed by Cohen (1988).

In the case of ordinal data, the *Dynamic Iota Index* shows a
slightly inferior performance compared to *Krippendorff’s Alpha*,
but the predictive power of both measures remains very high.

The Iota Concept provides cut-off values for several measures on the scale level. The following table reports the values that are currently recommended.

measure | minimum | satisfactory | good | excellent |
---|---|---|---|---|

Dynamic Iota Index | 0.829 | 0.961 | 0.985 | 1* |

Static Iota Index | 0.686 | 0.853 | 0.898 | 1* |

Average Iota | 0.693 | 0.847 | 0.875 | 1* |

Minimum Iota | 0.623 | 0.785 | 0.812 | 1* |

The *minimal* values imply the expectation that the estimated
and true association/correlation do not deviate more than .3.
Furthermore, these values justify the expectation that the risk of Type
I errors is less than 10%.

The cut-off value for *satisfactory* justifies the expectation
that the estimated and true association/correlation do not deviate more
than .1 and that the risk of Type I errors is less than 5%.

The values for *good* imply that the estimated and true
association/correlation do not deviate more than .3 with a certainty of
95%. Furthermore, these values guarantee that the risk of Type I errors
is less than 10 % with a certainty of 95%.

Values of the category *excellent* ensure with a certainty of
95% that the risk of Type I errors is less than 5% and the deviation
between estimated and true sample association/correlation exceeds not
more than .1. Please note that this degree of certainty is not
completely reached for all measures.

The presented cut-off values are only rules of thumb. They are
derived from the situations demanding the most reliability. More
situation-specific cut-off values can be calculated with the function
`get_consequences()`

. Please refer to the vignette
“Calculating consequences and cut-off values”.

Florian Berding and Julia Pargmann (2022). Iota Reliability Concept of the Second Generation. Measures for Content Analysis Done by Humans or Artificial Intelligence. Berlin: Logos. https://doi.org/10.30819/5581

Florian Berding, Elisabeth Riebenbauer, Simone Stuetz, Heike Jahncke, Andreas Slopinski, and Karin Rebmann (2022). Performance and Configuration of Artificial Intelligence in Educational Settings. Introducing a New Reliability Concept Based on Content Analysis. Frontiers in Education. https://doi.org/10.3389/feduc.2022.818365