difficult instances

USAGE SUMMARY

The phrase "difficult instances" is correct and usable in written English.
It can be used to refer to challenging situations or examples that are hard to deal with or understand. Example: "In the study, we analyzed several difficult instances where the data did not align with our expectations."

✓ Grammatically correct

Science

News & Media

Human-verified examples from authoritative sources

Exact Expressions

14 human-written examples

"[González] had the character to kick two penalties at very difficult instances," said Díaz.

The Guardian - Sport

A testbed of difficult instances of the problem are created to evaluate the performance of the GA.

Computers & Operations Research

Moreover, quantum annealing proved competitive when compared with the best algorithms on most of the difficult instances from the DIMACS benchmarks.

Discrete Optimization

Difficult instances with up to 50 potential plants and 100 customers, and largest easy instances, can be solved in one CPU hour.

European Journal of Operational Research

The CoDE has been used to solve three difficult instances of the design problem, and the optimization goal in each example is easily achieved.

Scientia Iranica

However, as we will show in this paper, some general purpose methods and the ideas on which they are built can provide guidance towards the efficient solution of difficult instances.

European Journal of Operational Research

Human-verified similar examples from authoritative sources

Similar Expressions

45 human-written examples

The reasons were essentially those already observed, but interestingly enough, the two tools did not (usually) fail on the same instances, meaning that a difficult instance for one tool might not be so difficult for the other.

Algorithms for Molecular Biology

The fact that CCP is intractable (coNP-complete) means that there exist difficult problem instances that take exponential time in the worst case, while efficient algorithms for CCP exist when the number of policies is not too large.

EURASIP Journal on Wireless Communications and Networking

Running times never exceeded the imposed deadline of 12 hours and altogether the tool failed only on few very difficult problem instances (always due to memory shortage).

Algorithms for Molecular Biology

Furthermore, the emerging consolidated model is compared to relevant algorithms from the literature for a set of difficult bidimensional instances from lattice protein models.

BioData Mining

That makes it difficult, for instance, for women who need maternity leave.

The Guardian

Expert writing Tips

Best practice

To enhance clarity in technical writing, follow up the phrase "difficult instances" with a concise explanation of what makes those instances challenging, such as complex variables or conflicting data points.

Common error

Avoid using "difficult instances" as a vague label for all challenges. Instead, clearly specify the characteristics or factors that make these instances particularly complex, ensuring your audience understands the precise nature of the difficulty.

Linguistic Context

The phrase "difficult instances" primarily functions as a descriptive phrase. It serves to characterize specific examples or situations as challenging or complex. As confirmed by Ludwig, the phrase is correct and usable in written English.

Expression frequency: Uncommon

Frequent in

Science

50%

News & Media

47%

Formal & Business

3%

Less common in

Encyclopedias

0%

Wiki

0%

Reference

0%

Ludwig's WRAP-UP

The phrase "difficult instances" is a grammatically sound and usable expression that serves to pinpoint challenging or complex examples within a given context. Ludwig confirms its correctness and usability. Predominantly found in scientific and news-related domains, it allows for focused analysis and problem-solving. While alternatives like "challenging cases" or "complex situations" exist, "difficult instances" provides a specific emphasis on the challenging nature of the examples at hand. When using the phrase, ensure clarity by specifying what makes these instances difficult and avoid overgeneralization.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

challenging cases

Replaces 'instances' with 'cases', emphasizing the specific occurrences being challenging.

complex situations

Substitutes 'difficult' with 'complex' and 'instances' with 'situations', highlighting intricacy.

problematic examples

Uses 'problematic' instead of 'difficult' and 'examples' in place of 'instances', focusing on the troublesome nature of the examples.

tricky situations

Replaces 'difficult' with 'tricky', suggesting a need for careful handling.

complicated scenarios

Substitutes 'difficult' with 'complicated' and 'instances' with 'scenarios', highlighting the complexity of the situations.

tough cases

Replaces 'difficult' with 'tough', suggesting resilience is needed.

hard examples

Uses 'hard' instead of 'difficult', directly indicating the examples are not easy.

demanding circumstances

Substitutes 'difficult' with 'demanding' and 'instances' with 'circumstances', focusing on the high requirements.

critical junctures

Replaces 'difficult' with 'critical' and 'instances' with 'junctures', emphasizing moments of high importance.

sensitive situations

Substitutes 'difficult' with 'sensitive' and 'instances' with 'situations', suggesting the situations require tact.

FAQs

How can I use "difficult instances" in a sentence?

You can use "difficult instances" to describe challenging examples or situations, such as, "The algorithm struggled with certain "difficult instances" due to incomplete data".

What are some alternatives to "difficult instances"?

Alternatives include "challenging cases", "complex situations", or "problematic examples", depending on the context.

When is it appropriate to use "difficult instances" in writing?

It's appropriate when you need to specifically highlight examples or situations that present significant challenges or complexities in a particular context, such as data analysis or problem-solving.

What makes "difficult instances" different from "difficult problems"?

"Difficult instances" typically refer to specific occurrences or examples that are challenging, whereas "difficult problems" refer to broader, more general issues that need resolution. The former is more granular and context-specific.