item variances

USAGE SUMMARY

The phrase "item variances" is correct and usable in written English.
It can be used in contexts related to inventory management, accounting, or data analysis to refer to differences or discrepancies in items. Example: "The report highlighted several item variances that need to be addressed before finalizing the budget."

✓ Grammatically correct

Science

Human-verified examples from authoritative sources

Exact Expressions

12 human-written examples

had low item variances explained.

Evolution: Education and Outreach

Coefficient alpha is computed from the item variances with the ratio of variances as the sum of the n item variances divided by the total test variance.

Human-centric Computing and Information Sciences

Strict factorial invariance implies that the factor structure, factor loadings, item intercepts and residual item variances are equal across samples.

Plosone

Fourth, the residual item variances (not explained by the latent trait(s)) are equal across samples (homogeneity of the residual variances, 'strict factorial invariance').

Plosone

As a general observation, item variances were much larger than subject variances (Table 1).

Annals of the New York Academy of Sciences

An initial omnibus test of measurement invariance often entails a comparison of the covariance matrix of item variances and covariances between groups.

Health and Quality of Life Outcomes

Human-verified similar examples from authoritative sources

Similar Expressions

48 human-written examples

Four tests were conducted: 1. Equal item variance: Items measuring the same concept should have roughly equal standard deviations and should be around 1.0 (for 5-choice response scales) [ 13]. 2. Equality of item-scale correlations: Items in each scale should contain approximately the same proportion of information about the concept being measured.

Health and Quality of Life Outcomes

Seventeen and 15% of the item variance indicated that items differed in difficulty to a large extent.

Language Testing in Asia

Factor 1 (which accounted for 29% of item variance) was defined by six of the scale items.

Fields Mathematics Education Journal

Five statements were removed from the current analyses because of very low item variance for these items that was accounted for by their corresponding constructs.

Evolution: Education and Outreach

The third Factor was defined by five of the scale items, accounted for 8% of item variance, and was labeled value of mathematics.

Fields Mathematics Education Journal

Expert writing Tips

Best practice

When reporting "item variances", ensure you clearly define what constitutes an "item" in your specific context (e.g., survey question, test question, inventory product) to avoid ambiguity.

Common error

Avoid incorrectly attributing variance to "items" when the true source of variation lies in the subjects or respondents. Clearly differentiate between "item variances" (differences in how items perform) and subject variances (differences between individuals).

Linguistic Context

The phrase "item variances" functions as a noun phrase, typically acting as the subject or object of a sentence. It refers to the statistical dispersion or variability observed within a set of items, such as questions in a survey or tasks in a test. Ludwig confirms its use in various research contexts.

Expression frequency: Uncommon

Frequent in

Science

100%

Less common in

News & Media

0%

Formal & Business

0%

Academia

0%

Ludwig's WRAP-UP

In summary, "item variances" is a technical noun phrase primarily used in scientific and academic research to describe the variability among items in a measurement instrument. Ludwig AI confirms the phrase is grammatically correct and usable. The phrase is most commonly found in the context of science and statistics. Related phrases include "item variability" and "item-level variation". A key writing tip is to clearly define "item" in your specific context to avoid ambiguity. Common errors include confusing "item variances" with subject variances. Understanding and appropriately addressing "item variances" is critical for ensuring the reliability and validity of research instruments.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

item variability

Focuses on the degree to which items differ, highlighting the spread of values rather than the statistical variance.

item-level variation

Emphasizes that the variation is specifically at the individual item level, rather than across subjects or other groupings.

differences among items

A more general way to refer to the variations between items, avoiding statistical jargon.

variation in item responses

Specifies that the variation is related to how people respond to the items.

item score dispersion

Highlights the spread or scattering of scores for each item, implying a statistical distribution.

inconsistency across items

Focuses on the lack of uniformity or agreement among the items.

item response heterogeneity

Uses a more technical term, heterogeneity, to describe the differences in item responses.

item discrimination differences

Highlights how well each item differentiates between respondents with different levels of the measured trait.

item characteristic curve variation

Specifically refers to variations in the item characteristic curves, a concept from item response theory.

differential item functioning

A technical term referring to instances where items function differently for different groups of respondents.

FAQs

How are "item variances" used in statistical analysis?

"Item variances" are used to assess the variability within individual items of a scale or test. They are important for determining reliability, identifying problematic items, and understanding the structure of the data.

What does a low "item variance" indicate?

A low "item variance" suggests that responses to that item are very similar across all respondents, which may indicate that the item is not effectively discriminating between different levels of the construct being measured. It might be too easy or too difficult for the sample population.

How do "item variances" relate to Cronbach's alpha?

Cronbach's alpha is computed using the "item variances" and covariances. If the sum of "item variances" is greater than the scale variance, it can lead to a negative Cronbach's alpha, indicating instability in the scale, like with the two-item fishar subscale.

What are some factors that can affect "item variances"?

Factors such as negatively worded items, item difficulty, and the complexity of the items can influence "item variances". Also, sample characteristics and the design of the measurement instrument can play a role.