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Suppose there exists a new airline named Jetco that flies domestically across North America. Jetco recently had a study commissioned that tested the boarding time of every airline, and it came out that Jetco had the fastest average boarding times of any airline.

What factors could have biased this result, and what would you look into?

What could potentially bias the average boarding time in favor of an airline that only flies domestically?

What could potentially bias the average boarding time in favor of an airline that only flies domestically?

Boarding Times Bias

A new airline came out as the fastest average boarding times compared to other airlines.  What factors could have biased this result and what would you look into?

Let’s say that your company is running a standard control and variant AB test on a feature to increase conversion rates on the landing page. The PM checks the results and finds a .04 p-value.

How would you assess the validity of the result?

Experiment Validity

Let’s say we have a table with an <code>id</code> and <code>name</code> fields. The table holds over 100 million rows and we want to sample a random row in the table without throttling the database.

Write a query to randomly sample a row from this table.

Input:

<code>big_table</code> table

<table>
<thead>
<tr>
<th>Columns</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>id</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>name</code></td>
<td>VARCHAR</td>
</tr>
</tbody>
</table>

Write a query to randomly sample a row from a big table.

Random SQL Sample

Nuwave Solutions Salaries by Position

Overview BigBear.ai is seeking a Data Engineer to support a program in Honolulu, HI. As a Data Engineer, you will play a crucial role in designing, developing, and maintaining our Advana data infrastructure, pipelines and systems. Proficiency in ETL, Databricks, Python, Spark, Scala, JavaScript/JSON, SQL, and Jupyter Notebooks is crucial for ensuring efficient data ingest, processing and analysis. You will develop and manage ETL processes and data pipelines across various government platforms, working with a wide range of data types. This is an ideal opportunity to be part of one of the fastest growing AI/ML companies in the industry. At BigBear.ai, we're in this business together. We own it, we make it thrive, and we enjoy the challenges of our work. We know that our employees play the largest role in our continual success. That is why we foster an environment of growth and development, with an emphasis on opportunity, recognition, and work-life balance. We give the same high level of commitment to our employees that we give to our clients. If BigBear.ai sounds like the place where you want to be, we'd enjoy speaking with you. What you will do <ul><li>Design, develop, and implement end-to-end data pipelines, utilizing ETL processes and technologies such as Databricks, Python, Spark, Scala, JavaScript/JSON, SQL, and Jupyter Notebooks. </li> <li>Create and optimize data pipelines from scratch, ensuring scalability, reliability, and high-performance processing. </li> <li>Perform data cleansing, data integration, and data quality assurance activities to maintain the accuracy and integrity of large datasets. </li> <li>Leverage big data technologies to efficiently process and analyze large datasets, particularly those encountered in a federal agency. </li> <li>Troubleshoot data-related problems and provide innovative solutions to address complex data challenges. </li> <li>Implement and enforce data governance policies and procedures, ensuring compliance with regulatory requirements and industry best practices. </li> <li>Work closely with cross-functional teams to understand data requirements and design optimal data models and architectures. </li> <li>Collaborate with data scientists, analysts, and stakeholders to provide timely and accurate data insights and support decision-making processes. </li> <li>Maintain documentation for software applications, workflows, and processes. </li> <li>Stay updated with emerging trends and advancements in data engineering and recommend suitable tools and technologies for continuous improvement. </li> </ul>What you need to have Bachelor's Degree and 0 to 2 years of experience; 6 to 8 years with no degree <ul> <li>Clearance:TS/SCI clearance </li></ul> <ul> <li>1+ years of Python experience including developing, running, packaging, and testing Python scripts </li> <li>Experience with distributed version control systems (VCS) </li> <li>Experience with the entire ETL/ELT pipeline, including data ingestion, data normalization, data preparation, and database design </li> <li>Experience with conducting exploratory data analysis to communicate qualitative and quantitative findings to analysts </li> <li>Experience processing and fusing structured and unstructured data </li> <li>Experience with data engineering projects supporting data science and AI/ML workloads </li> <li>Experience creating solutions within a collaborative, cross-functional team environment in team sprint cycles </li> <li>Bachelors degree </li> </ul>What we'd like you to have <ul><li>Experience with using Palantir products for data manipulation, correlation, and visualization </li> <li>Experience with AWS or other cloud computing services </li> <li>Experience with Kafka and NiFi development </li> <li>Experience with containerization tools, including Docker and Kubernetes </li> <li>TS/SCI with Counterintelligence Polygraph </li> </ul>About BigBear.ai BigBear.ai is a leading provider of AI-powered decision intelligence solutions for national security, supply chain management, and digital identity. Customers and partners rely on BigBear.ais predictive analytics capabilities in highly complex, distributed, mission-based operating environments. Headquartered in Columbia, Maryland, BigBear.ai is a public company traded on the NYSE under the symbol BBAI. For more information, visit https://bigbear.ai/ and follow BigBear.ai on LinkedIn: @BigBear.ai and X: @BigBearai. What you will do <ul> <li>Design, develop, and implement end-to-end data pipelines, utilizing ETL processes and technologies such as Databricks, Python, Spark, Scala, JavaScript/JSON, SQL, and Jupyter Notebooks. </li> <li>Create and optimize data pipelines from scratch, ensuring scalability, reliability, and high-performance processing. </li> <li>Perform data cleansing, data integration, and data quality assurance activities to maintain the accuracy and integrity of large datasets. </li> <li>Leverage big data technologies to efficiently process and analyze large datasets, particularly those encountered in a federal agency. </li> <li>Troubleshoot data-related problems and provide innovative solutions to address complex data challenges. </li> <li>Implement and enforce data governance policies and procedures, ensuring compliance with regulatory requirements and industry best practices. </li> <li>Work closely with cross-functional teams to understand data requirements and design optimal data models and architectures. </li> <li>Collaborate with data scientists, analysts, and stakeholders to provide timely and accurate data insights and support decision-making processes. </li> <li>Maintain documentation for software applications, workflows, and processes. </li> <li>Stay updated with emerging trends and advancements in data engineering and recommend suitable tools and technologies for continuous improvement. </li> </ul>What you need to have Bachelor's Degree and 0 to 2 years of experience; 6 to 8 years with no degree <ul> <li>Clearance:TS/SCI clearance </li></ul> <ul> <li>1+ years of Python experience including developing, running, packaging, and testing Python scripts </li> <li>Experience with distributed version control systems (VCS) </li> <li>Experience with the entire ETL/ELT pipeline, including data ingestion, data normalization, data preparation, and database design </li> <li>Experience with conducting exploratory data analysis to communicate qualitative and quantitative findings to analysts </li> <li>Experience processing and fusing structured and unstructured data </li> <li>Experience with data engineering projects supporting data science and AI/ML workloads </li> <li>Experience creating solutions within a collaborative, cross-functional team environment in team sprint cycles </li> <li>Bachelors degree </li> </ul>

Overview BigBear.ai is seeking a Business Analyst. This role is integral in ensuring our clients IT products meet customer needs and align with business goals. You will support the mission and its leadership by identifying, eliciting, and decomposing requirements. You will also facilitate team and customer ceremonies and foster effective communication, both verbally and through written artifacts and documentation. Your role sits within a continuously evolving Agile and DevSecOps environment, requiring you to proactively adapt and contribute to the organizations maturation process. Your ultimate aim is to deepen and broaden your teams impact through the delivery of innovative, desirable, and mission critical software products. What you will do <ul><li>Analyzing and understand business needs and translating them into the governance artifacts and product backlog items </li></ul> <ul> <li>Performing AoAs and assessing courses of action by a variety of factors to include value, cost, feasibility, and risk </li> </ul><ul> <li>Performing estimation and complexity assessments of customer IT requests </li> </ul><ul> <li>Creation and management of conceptual delivery schedules and product roadmaps </li></ul> <ul> <li>Generating and managing artifacts and knowledge bases </li></ul> <ul> <li>Generating and managing body of evidence (BOE) generation and submission </li></ul> <ul> <li>Assist in test planning and management </li></ul> <ul> <li>Facilitating and refining team level ceremonies </li></ul> <ul> <li>Identifying, mapping, and tracking dependencies internal and external to the team </li></ul> <ul> <li>Collaborating with cross-functional teams to ensure efficient product development and delivery </li></ul> <ul> <li>Utilizing product management tools such as Jira, Confluence, and M365 to accomplish daily duties </li> </ul>What you need to have <ul><li>You must maintain a TS-SCI clearance </li> <li>Bachelors degree or equivalent practical experience </li></ul> <ul> <li>Understanding of the software development lifecycle (SDLC) </li></ul> <ul> <li>A general understanding of popular backend and frontend technologies </li> </ul><ul> <li>2 years of experience working on, or in direct support of a software development team or in an enterprise architecture organization </li> </ul><ul> <li>Experience working in Agile and Scrum methodologies </li></ul> <ul> <li>Familiarity with Cloud environments, particularly AWS </li></ul> <ul> <li>Experience with Confluence and Jira </li></ul> <ul> <li>Experience with the Microsoft 365 (M365) suite </li></ul> <ul> <li>Experience in backlog management, including Epic, Feature, User Story development, and refinement </li> </ul><ul> <li>Ability to be on-site 60% of the time at a client SCIF located in Washington D.C. </li> </ul><ul> <li>Strong verbal and non-verbal communication skills </li></ul> <ul> <li>Strong interpersonal skills, with the ability to work effectively in a team environment and build strong relationships with team members </li> </ul>What we'd like you to have <ul><li>Familiarity and experience performing analysis of alternatives (AoAs) </li> </ul><ul> <li>Familiarity and experience with the Intelligence Community (IC), and the intel cycle </li></ul> <ul> <li>Familiarity and experience with the Department of Homeland Security (DHS) </li></ul> <ul> <li>Familiarity and experience with Government risk management frameworks (RMF) and cyber security authorization processes </li> </ul><ul> <li>Masters degree or equivalent experience in a related field </li></ul> <ul> <li>Previous experience in a similar role </li></ul> <ul> <li>Familiarity and experience operating within the full software development lifecycle (SDLC) </li></ul> <ul> <li>Strong track record of successfully supporting the delivery valuable software products </li></ul> <ul> <li>Experience working with cross-functional teams in an Agile environment </li></ul> <ul> <li>Knowledge of user research methodologies and the ability to derive actionable insights </li></ul> <ul> <li>Proficiency in additional project management and collaboration tools </li></ul> <ul> <li>A passion for staying up-to-date with industry trends and emerging technologies </li></ul> <ul> <li>Strong stakeholder management skills and experience </li></ul> <ul> <li>Cloud budgeting and forecasting experience </li></ul> <ul> <li>Relevant certifications </li> </ul>About BigBear.ai BigBear.ai is a leading provider of AI-powered decision intelligence solutions for national security, supply chain management, and digital identity. Customers and partners rely on BigBear.ais predictive analytics capabilities in highly complex, distributed, mission-based operating environments. Headquartered in Columbia, Maryland, BigBear.ai is a public company traded on the NYSE under the symbol BBAI. For more information, visit https://bigbear.ai/ and follow BigBear.ai on LinkedIn: @BigBear.ai and X: @BigBearai. What you will do <ul> <li>Analyzing and understand business needs and translating them into the governance artifacts and product backlog items </li></ul> <ul> <li>Performing AoAs and assessing courses of action by a variety of factors to include value, cost, feasibility, and risk </li> </ul><ul> <li>Performing estimation and complexity assessments of customer IT requests </li> </ul><ul> <li>Creation and management of conceptual delivery schedules and product roadmaps </li></ul> <ul> <li>Generating and managing artifacts and knowledge bases </li></ul> <ul> <li>Generating and managing body of evidence (BOE) generation and submission </li></ul> <ul> <li>Assist in test planning and management </li></ul> <ul> <li>Facilitating and refining team level ceremonies </li></ul> <ul> <li>Identifying, mapping, and tracking dependencies internal and external to the team </li></ul> <ul> <li>Collaborating with cross-functional teams to ensure efficient product development and delivery </li></ul> <ul> <li>Utilizing product management tools such as Jira, Confluence, and M365 to accomplish daily duties </li> </ul>What you need to have <ul> <li>You must maintain a TS-SCI clearance </li> <li>Bachelors degree or equivalent practical experience </li></ul> <ul> <li>Understanding of the software development lifecycle (SDLC) </li></ul> <ul> <li>A general understanding of popular backend and frontend technologies </li> </ul><ul> <li>2 years of experience working on, or in direct support of a software development team or in an enterprise architecture organization </li> </ul><ul> <li>Experience working in Agile and Scrum methodologies </li></ul> <ul> <li>Familiarity with Cloud environments, particularly AWS </li></ul> <ul> <li>Experience with Confluence and Jira </li></ul> <ul> <li>Experience with the Microsoft 365 (M365) suite </li></ul> <ul> <li>Experience in backlog management, including Epic, Feature, User Story development, and refinement </li> </ul><ul> <li>Ability to be on-site 60% of the time at a client SCIF located in Washington D.C. </li> </ul><ul> <li>Strong verbal and non-verbal communication skills </li></ul> <ul> <li>Strong interpersonal skills, with the ability to work effectively in a team environment and build strong relationships with team members </li> </ul>

Overview BigBear.ai is seeking a Software Engineer on an exciting upcoming Cyber Operations contract award The Software Engineer develops, maintains, and enhances complex and diverse software systems (e.g., processing-intensive analytics, novel algorithm development, manipulation of extremely large data sets, real-time systems, and business management information systems) based upon documented requirements. Works indi.vidually or as part of a team. Reviews and tests software components for adherence to the design requirements and d,ocuments test results. Resolves software problem reports. Utilizes software development and software design methodologies appropriate to the development environment. Provides specific input to the software components of system design to include hardware/software tradeoffs, software reuse, use of Commercial Off-the-shelf (COTS)/Government Offthe-shelf {GOTS) in place of new development, and requirements analysis and synthesis from system level to individual software components. What you will do <ul><li>Analyze user requirements to derive software design and performance requirements</li><li>Debug existing software and correct defects</li><li>Provide recommendations for improving documentation and software development process standards</li><li>Design and code new software or modify existing software to add new features</li><li>Integrate existing software into new or modified systems or operating environments</li><li>Develop simple data queries for existing or proposed databases or data repositories</li><li>Write or review software and system documentation</li><li>Serve as team lead at the level appropriate to the software development process being used on any particular project</li><li>Design or implement complex database or data repository interfaces/queries</li><li>Develop or implement algorithms to meet or exceed system performance and functional standards</li><li>Assist with developing and executing test procedures for software components</li><li>Develop software solutions by analyzing system performance standards, confer with users or system engineers; analyze systems flow, data usage and work processes; and investigate problem areas</li><li>Modify existing software to correct errors, to adapt to new hardware, or to improve its performance</li><li>Design, develop and modify software systems, using scientific analysis and mathematical models to predict and measure outcome and consequences of design</li><li>Design or implement complex algorithms requiring adherence to strict timing, system resource, or interface constraints; Perform quality control on team products</li><li>Implement recommendations for improving documentation and software development process standards</li><li>Oversee one or more software development teams and ensure the work is completed in accordance with the constraints of the software development process bei_ng used on any particular project</li><li>Confer with system engineers and hardware engineers to derive software requirements and to obtain information on project limitations and capabilities, performance requirements and interfaces</li><li>Coordinate software system installation and monitor equipment functioning to ensure operational specifications are met</li><li>Recommend new technologies and processes for complex software projects</li><li>Serve as the technical lead of multiple software development teams</li><li>Select the software development process in coordination with the customer and system engineering</li><li>Ensure quality control of all developed and modified software</li><li>Delegate programming and testing responsibilities to one or more teams and monitor their performance</li></ul> What you need to have <ul><li>Must possess a TS/SCI with FSP</li><li>Twenty (20} years' experience as a SWE in programs and contracts of similar scope, type, and complexity is required. Bachelor's degree in Computer Science or related discipline from an accredited college or university is required. Four (4) years of additional SWE experience on projects with similar -software processes may be substituted for a bachelor's degree.</li></ul> What we'd like you to have <ul><li>A thirst for knowledge and a desire to learn</li></ul> About BigBear.ai BigBear.ai is a leading provider of AI-powered decision intelligence solutions for national security, supply chain management, and digital identity. Customers and partners rely on BigBear.ai's predictive analytics capabilities in highly complex, distributed, mission-based operating environments. Headquartered in Columbia, Maryland, BigBear.ai is a public company traded on the NYSE under the symbol BBAI. For more information, visit https://bigbear.ai/ and follow BigBear.ai on LinkedIn: @BigBear.ai and X: @BigBearai. What you will do <ul><li>Analyze user requirements to derive software design and performance requirements</li><li>Debug existing software and correct defects</li><li>Provide recommendations for improving documentation and software development process standards</li><li>Design and code new software or modify existing software to add new features</li><li>Integrate existing software into new or modified systems or operating environments</li><li>Develop simple data queries for existing or proposed databases or data repositories</li><li>Write or review software and system documentation</li><li>Serve as team lead at the level appropriate to the software development process being used on any particular project</li><li>Design or implement complex database or data repository interfaces/queries</li><li>Develop or implement algorithms to meet or exceed system performance and functional standards</li><li>Assist with developing and executing test procedures for software components</li><li>Develop software solutions by analyzing system performance standards, confer with users or system engineers; analyze systems flow, data usage and work processes; and investigate problem areas</li><li>Modify existing software to correct errors, to adapt to new hardware, or to improve its performance</li><li>Design, develop and modify software systems, using scientific analysis and mathematical models to predict and measure outcome and consequences of design</li><li>Design or implement complex algorithms requiring adherence to strict timing, system resource, or interface constraints; Perform quality control on team products</li><li>Implement recommendations for improving documentation and software development process standards</li><li>Oversee one or more software development teams and ensure the work is completed in accordance with the constraints of the software development process bei_ng used on any particular project</li><li>Confer with system engineers and hardware engineers to derive software requirements and to obtain information on project limitations and capabilities, performance requirements and interfaces</li><li>Coordinate software system installation and monitor equipment functioning to ensure operational specifications are met</li><li>Recommend new technologies and processes for complex software projects</li><li>Serve as the technical lead of multiple software development teams</li><li>Select the software development process in coordination with the customer and system engineering</li><li>Ensure quality control of all developed and modified software</li><li>Delegate programming and testing responsibilities to one or more teams and monitor their performance</li></ul> What you need to have <ul><li>Must possess a TS/SCI with FSP</li><li>Twenty (20} years' experience as a SWE in programs and contracts of similar scope, type, and complexity is required. Bachelor's degree in Computer Science or related discipline from an accredited college or university is required. Four (4) years of additional SWE experience on projects with similar -software processes may be substituted for a bachelor's degree.</li></ul>

Overview BigBear.ai is seeking a Data Engineer to support a program in Crystal City, VA (Hybrid 2-3 days in office). As a Data Engineer, you will play a crucial role in designing, developing, and maintaining our Advana data infrastructure and systems. Your expertise in ETL, Databricks, Python, Spark, Scala, JavaScript/JSON, SQL, and Jupyter Notebooks will be essential in ensuring efficient data processing and analysis. This is an ideal opportunity to be part of one of the fastest growing AI/ML companies in the industry. At BigBear.ai, we're in this business together. We own it, we make it thrive, and we enjoy the challenges of our work. We know that our employees play the largest role in our continual success. That is why we foster an environment of growth and development, with an emphasis on opportunity, recognition, and work-life balance. We give the same high level of commitment to our employees that we give to our clients. If BigBear.ai sounds like the place where you want to be, we'd enjoy speaking with you. This position requires an active Secret Clearance. What you will do <ul><li>Design, develop, and implement end-to-end data pipelines, utilizing ETL processes and technologies such as Databricks, Python, Spark, Scala, JavaScript/JSON, SQL, and Jupyter Notebooks. </li><li>Create and optimize data pipelines from scratch, ensuring scalability, reliability, and high-performance processing. </li><li>Perform data cleansing, data integration, and data quality assurance activities to maintain the accuracy and integrity of large datasets. </li><li>Leverage big data technologies to efficiently process and analyze large datasets, particularly those encountered in a federal agency. </li><li>Troubleshoot data-related problems and provide innovative solutions to address complex data challenges. </li><li>Implement and enforce data governance policies and procedures, ensuring compliance with regulatory requirements and industry best practices. </li><li>Work closely with cross-functional teams to understand data requirements and design optimal data models and architectures. </li><li>Collaborate with data scientists, analysts, and stakeholders to provide timely and accurate data insights and support decision-making processes. </li><li>Maintain documentation for software applications, workflows, and processes. </li><li>Stay updated with emerging trends and advancements in data engineering and recommend suitable tools and technologies for continuous improvement. </li></ul>What you need to have<ul><li>Secret clearance is required </li><li>Minimum of 5+ years of experience as a Data Engineer, with demonstrated experience creating data pipelines from scratch. </li><li>High level of proficiency in ETL processes and demonstrated, hands-on experience with technologies such as Databricks, Python, Spark, Scala, JavaScript/JSON, SQL, and Jupyter Notebooks. </li><li>Strong problem-solving skills and ability to solve complex data-related issues. </li><li>Demonstrated experience working with large datasets and leveraging big data technologies to process and analyze data efficiently. </li><li>Understanding of data modeling/visualization, database design principles, and data governance practices. </li><li>Excellent communication and collaboration skills, with the ability to work effectively with cross-functional teams. </li><li>Detail-oriented mindset with a commitment to delivering high-quality results. </li><li>Must be in the DC Metro area and available to work onsite in Crystla City, VA hybrid/remote. </li><li>DOD or IC-related experience. </li></ul>What we'd like you to have<ul><li>Knowledge of Qlik/Qlik Sense, QVD/QlikView, and Qlik Production Application Standards (QPAS) is a significant plus. </li><li>Recent DoD or IC-related experience. </li><li>Previous experience with Advana is a plus </li></ul>About BigBear.ai BigBear.ai delivers AI-powered analytics and cyber engineering solutions to support mission-critical operations and decision-making in complex, real-world environments. BigBear.ais customers, which include the US Intelligence Community, Department of Defense, the US Federal Government, as well as customers in manufacturing, healthcare, commercial space, and other sectors, rely on BigBear.ais solutions to see and shape their world through reliable, predictive insights and goal-oriented advice. Headquartered in Columbia, Maryland, BigBear.ai is a global, public company traded on the NYSE under the symbol BBAI. For more information, please visit: http://bigbear.ai/ and follow BigBear.ai on Twitter: @BigBearai. What you will do <ul><li>Design, develop, and implement end-to-end data pipelines, utilizing ETL processes and technologies such as Databricks, Python, Spark, Scala, JavaScript/JSON, SQL, and Jupyter Notebooks. </li><li>Create and optimize data pipelines from scratch, ensuring scalability, reliability, and high-performance processing. </li><li>Perform data cleansing, data integration, and data quality assurance activities to maintain the accuracy and integrity of large datasets. </li><li>Leverage big data technologies to efficiently process and analyze large datasets, particularly those encountered in a federal agency. </li><li>Troubleshoot data-related problems and provide innovative solutions to address complex data challenges. </li><li>Implement and enforce data governance policies and procedures, ensuring compliance with regulatory requirements and industry best practices. </li><li>Work closely with cross-functional teams to understand data requirements and design optimal data models and architectures. </li><li>Collaborate with data scientists, analysts, and stakeholders to provide timely and accurate data insights and support decision-making processes. </li><li>Maintain documentation for software applications, workflows, and processes. </li><li>Stay updated with emerging trends and advancements in data engineering and recommend suitable tools and technologies for continuous improvement. </li></ul>What you need to have <ul><li>Secret clearance is required </li><li>Minimum of 5+ years of experience as a Data Engineer, with demonstrated experience creating data pipelines from scratch. </li><li>High level of proficiency in ETL processes and demonstrated, hands-on experience with technologies such as Databricks, Python, Spark, Scala, JavaScript/JSON, SQL, and Jupyter Notebooks. </li><li>Strong problem-solving skills and ability to solve complex data-related issues. </li><li>Demonstrated experience working with large datasets and leveraging big data technologies to process and analyze data efficiently. </li><li>Understanding of data modeling/visualization, database design principles, and data governance practices. </li><li>Excellent communication and collaboration skills, with the ability to work effectively with cross-functional teams. </li><li>Detail-oriented mindset with a commitment to delivering high-quality results. </li><li>Must be in the DC Metro area and available to work onsite in Crystla City, VA hybrid/remote. </li><li>DOD or IC-related experience. </li></ul>

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Nuwave Solutions Interview Questions

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