Del 17 al 28 de julio de 2023 SAS entrenará de forma gratuita a estudiantes de Latinoamérica y recién egresados para desarrollar las habilidades demandadas en el mercado laboral. El entrenamiento total tiene un valor aproximado de 7,500 dólares. Al finalizar los estudiantes se podrán certificar de forma gratuita. La
A Toeplitz matrix is a banded matrix. You can construct it by specifying the parameters that are constant along each diagonal, including sub- and super-diagonals. For a square N x N matrix, there is one main diagonal, N-1 sub-diagonals, and N-1 super-diagonals, for a total of 2N-1 parameters. In statistics and applied
SoDA를 이용해 쉽게 배우는 데이터 과학 #1 SoDA(SAS OnDemand for Academics)는 SAS가 무료로 제공하는 교육용 데이터 분석 소프트웨어 프로그램입니다. 앞으로 4회에 걸쳐 'SoDA 를 이용해 쉽게 배우는 데이터 과학'을 자세히 소개해 드리도록 하겠습니다. SoDA란? SoDA (SAS OnDemand for Academics; SoDA)는 데이터 과학을 처음 배우는 입문자들에게 SAS를 무료로 배울 수 있도록
A previous article explains the Spearman rank correlation, which is a robust cousin to the more familiar Pearson correlation. I've also discussed why you might want to use rank correlation, and how to interpret the strength of a rank correlation. This article gives a short example that helps you to
Since the COVID-19 pandemic began, video presentations and webcasts have become a regular routine for many of us. On days that I will be using my webcam, I wear a solid-color shirt. If I don't plan to be on camera, I can wear a pinstripe Oxford shirt. Why the difference?
Real-world data often exhibits extreme skewness. It is not unusual to have data span many orders of magnitude. Classic examples are the distributions of incomes (impoverished and billionaires) and population sizes (small countries and populous nations). The readership of books and blog posts show a similar distribution, which is sometimes
This year, SAS Innovate in Orlando brought executives and other industry luminaries together to inspire attendees to use analytics to outpace tomorrow. Data and analytics enables you to get to the true value of a human being. Michael Lewis, Author of Moneyball Chief Marketing Officer Jenn Chase, who hosted the event,
이스탄불 광역시, 세계적인 벽돌 제조사 ‘위너버거’, SAS Viya로 제품품질 확보와 지속가능성 향상 모두 달성 친환경 비즈니스 전략을 지원하기 위해 주요 기업들은 AI, 머신러닝 및 사물인터넷(IoT) 분석에 더욱 더 의존하고 있습니다. 이러한 기술은 탄소 및 폐기물 배출량을 줄임으로써 지속가능성을 향상시키고, 더 똑똑하고 효율적인 운영 방법을 개발하는 데 도움이 되고 있습니다. SAS는
Labeling objects in graphs can be difficult. SAS has a long history of providing support for labeling markers in scatter plots and for labeling regions on a map. This article discusses how the SGPLOT procedure decides where to put a label for a polygon. It discusses the advantages and disadvantages
This year six teams from Benelux joined the global competition. These teams took on exciting challenges: from unlocking privacy-sensitive healthcare data with synthetic data to optimizing cheese production and much more! With access to the latest SAS software and SAS mentors, they were building innovative solutions to real-world problems. Two
SAS supports many ways to compute the rank of a numeric variable and to handle tied values. However, sometimes I need to rank the values in a character categorical variable. For example, the values {"Male", "Female", "Male"} have ranks {2, 1, 2} because, in alphabetical order, "Female" is the first-ranked
‘SAS 이노베이트 2023’에서 최신 AI, 클라우드 분석 기술 및 사례 발표 세계적인 분석 선두 기업 SAS가 5월 8일부터 10일까지(미국 현지 시간) 미국 플로리다주 올랜도에서 ‘SAS 이노베이트 2023(SAS Innovate 2023)’ 행사를 개최했습니다. ‘SAS 이노베이트’는 전 세계 산업별 전문가와 오피니언 리더들이 참석하는 SAS의 연례 비즈니스 컨퍼런스입니다. 이번 행사에서는 SAS Viya 제품의 놀라운
"For those not knee-deep in the ModelOps process, the process may seem simple," says Ankit Sinha, Director of Product Management at Experian: "You build the model, deploy the model and reap the benefits." But the process starts to become very complex when you're using multiple database systems and data sources
A previous article defines the silhouette statistic (Rousseeuw, 1987) and shows how to use it to identify observations in a cluster analysis that are potentially misclassified. The article provides many graphs, including the silhouette plot, which is a bar chart or histogram that displays the distribution of the silhouette statistic
"Demand planning is a team sport," says Davis Wu, Global Lead of Demand Planning and Analytics at Nestlé S.A. The team at Nestlé includes demand planners, demand analysts and data scientists, who all work together to ensure that Nestlé products remain in stock. Many demand analysts can be seen as
Empirical Mode Decomposition (EMD) is a powerful time-frequency analysis technique that allows for the decomposition of a non-stationary and non-linear signal into a series of intrinsic mode functions (IMFs). The method was first introduced by Huang et al. in 1998 and has since been widely used in various fields, such as signal processing, image analysis, and biomedical engineering.
En el ámbito de la seguridad, la capacidad de investigación es esencial. Sin embargo, en un mundo cada vez más digital, puede resultar difícil mantenerse al día con las últimas herramientas y técnicas para realizar investigaciones de manera eficiente y efectiva. En este post, exploraremos las mejores prácticas y beneficios
Mental Health Month is an important time to honor and raise awareness around mental illness and mental wellness. Correcting and combating stigma and discrimination, including with data, is one of the month’s major goals. It’s hard to talk about mental health without also addressing substance use disorders (including opioids), homelessness
Assigning observations into clusters can be challenging. One challenge is deciding how many clusters are in the data. Another is identifying which observations are potentially misclassified because they are on the boundary between two different clusters. Ralph Abbey's 2019 paper ("How to Evaluate Different Clustering Results") is a good way
The term "partner" is often overused in the technology industry. We partner with cloud providers, we partner with systems integrators, we partner with our customers – and so much more. But when a genuine partnership comes together to build something complex and successful, you can't deny the importance of that
SAS' Ji Shen introduces you to an effective solution for modeling and forecasting count time series.
A lot of programmers have been impressed by the ability of ChatGPT, GPT-4, and Bing Chat to write computer programs. Recently, I wrote an article that discusses an elementary programming assignment, called FizzBuzz, which is sometimes used as part of a hiring process to assess a candidate's basic knowledge of
What do you get when you mix leaders from every industry, a hall-of-fame basketball coach and a best-selling author together in three days? SAS Innovate in Orlando, of course. As organizations navigate this changing economic landscape, many are turning to analytics and AI to help them stay ahead of the
Recently, I learned about an elementary programming assignment called the FizzBuzz program. Some companies use this assignment for the first round of interviews with potential programmers. A competent programmer can write FizzBuzz in 5-10 minutes, which leaves plenty of time to discuss other topics. If an applicant can't complete the
지난 3년간 팬데믹으로 인한 경기 침체와 혼란은 기업들의 경영환경에 큰 변화와 전환점을 가져왔습니다. 이러한 경제, 사회적 위기 상황에서 기업에게 필요한 것은 바로 요동치는 환경에서도 흔들리지 않는 ‘회복탄력성’을 확보하는 것입니다. SAS가 2,400여명의 기업 경영진을 대상으로 진행한 조사결과, 97%의 경영진들이 회복탄력성의 중요성은 인지하고 있는 반면 절반 이상(53%)의 응답자들이 자사의 회복탄력성이 부족한 수준이라고
In SAS, you can approximate the exponential of a matrix by using the EXPMATRIX function in SAS IML software. This article discusses the exponential of a matrix: what it is, how to compute it, why it is useful, and why you should think of it as a linear map that
Over 40 years ago Steven Hayes developed ACT Therapy (pronounced as the word "act") which incorporates practices of psychological flexibility and a focus on values. For Work/Life's recent email series, A Month of Values Based Living, Triangle area therapists shared introductions to the six components of ACT Therapy and related
Who is responsible for ensuring that new AI technologies are fair and ethical? Does that responsibility land on AI developers? On innovators? On CEOs? Or is the responsibility more widespread? At SAS, we believe that it is everyone’s duty to innovate responsibly with AI. We believe that adhering to trustworthy
In a previous article, I showed how to overlay a density estimate on a histogram by using the Graph Template Language (GTL). However, a SAS programmer asked how to overlay a curve on a histogram when the curve is not a density estimate. In this case, the vertical axis for
はじめに 統計的因果推論における1つの達成目標として「介入を行った場合には行わなかった場合と比較してどの程度結果（アウトカム）が変わったのか」という因果的な疑問に対し、定量的に答えることが挙げられるかと思います。以前のコラムでは、こういった因果効果を数学的・統計学的に議論していくために潜在アウトカムという考え方を導入し、その値を推定していくために重要ないくつかの仮定について紹介を行いました。この因果効果の推定の手法には様々なものがありますが、次回以降のコラムで紹介をする交絡調整に基づく因果効果の推定手法 (e.g., 回帰、層別化、傾向スコアを用いた手法）では、興味のある因果効果の推定値をバイアスなく得るためには、交絡や選択バイアスの調整に必要な全ての変数が完全に特定・測定されているという仮定が成立している必要があります。この仮定はデータからその成立を検証することはできず、もしもいずれかが成立しない場合には得られる推定値にはバイアスが含まれ、いわゆる残差交絡 (redidual confounding) が存在する状況となります。現実的に仮定が全て厳密に成立するケースというのは比較的稀ですので、そのような意味では大部分の研究結果（特に観察研究）・解析結果には一定のバイアスが含まれているとみることもできるかと思います。ただし交絡調整に基づく手法がダメだと言っているわけではなく、調整が不完全ながらもバイアスを軽減することは十分に意義があり、また最終的に結果に含まれるであろうバイアスの大きさとその方向（過大評価 or 過小評価）を議論することが重要かと思います。 今回のコラムでは、操作変数法（instrumental variable methods, IV methods）という因果効果の推定手法について紹介と解説を行っていきます。この推定手法は、操作変数 (instrumental variable, instrument) と呼ばれるいくつかの条件を満たす特殊な変数を利用することで因果効果の推定を行う手法になります。医学分野では、先行研究の結果（e.g., 医学的な知見）から交絡因子となりうる変数の特定・測定が比較的容易であることから先ほど言及した交絡調整に基づく推定手法が用いられるケースが比較的多いですが、経済学や社会科学といった分野ではそもそもの特定が出来なかったり、仮に交絡因子であろうと見込んだ場合であってもそれを測定することができないケースが非常に多く存在します。そのため交絡調整に基づかない手法である操作変数法というのは経済学や社会科学において、特にその理論が発展してきたという歴史的な背景があります。なお詳細については後述しますが、操作変数法は交絡因子の測定を必要としないというメリットもある一方、いくつかの検証不可能な仮定に基づく手法です。したがって、解析を行う研究・データにおいて因果効果の推定のために要求される仮定の成立を認めることがどの程度妥当であるかの議論が他の手法と同様に必要であることにご注意ください。 操作変数の3条件 操作変数法では、ある介入AのアウトカムYに対する因果効果を推定するために以下の3つの条件を満たす変数Zを利用します。この変数Zは操作変数 (instrumental variable, instrument) と呼ばれます。 操作変数の3条件 (Theree instrumental conditions) Z is associated with A ZはAと関連する Z does not affect Y except through its potential effect on Y ZはYに対してAを介した以外の効果を持たない Z
