DFT – Trigonometric representation

DFT – Trigonometric representation

There have been several inquiries since the time we released our first entry on DFT, especially about using the DFT components to represent the input data set as the sum of the trigonometric sine-cosine functions. The inquiries were motivated by…

NumXL New Order System

NumXL New Order System

We are excited to announce a new change to our online order system: we have switched our payment processor to Fast Spring (Santa Barbara, CA USA). Using Fast Spring’s simple yet secure shopping cart system, we are able to offer…

Making Sense of Diesel Prices

Making Sense of Diesel Prices

In this case, we examine the highway retail price ($/Gallon) for “No.2 Ultra Low Sulfur (0-15 ppm) Diesel” in the EIA nine (9) PADD regions and carry on principal component analysis in an attempt to find a minimal subset of…

Calculating CAPM Beta

Calculating CAPM Beta

In this paper, we will apply simple linear regression to calculate the CAPM beta for two technology stocks: Microsoft (MSFT) and IBM, then validate the model’s assumptions, identify influential data-points (e.g. outlier), ensure structural stability over the data sample, and…

NumXL Price Change Coming

NumXL Price Change Coming

With great reluctance, Spider will be increasing the price of a NumXL license with the release of NumXL 1.60 (Apache). The NumXL annual license price will increase to $200 USD/yr (a $50 USD increase) for new customers only. That means all…

NumXL customers’ reviews

NumXL customers’ reviews

We’d love to hear your ideas and experience with NumXL and our support. To keep the reviews objective and let us truly assess where we stand in terms of service quality, we are asking you to leave anything special aside…

NumXL 1.59 TUCSON is released

NumXL 1.59 TUCSON is released

We are thrilled to announce the official release of a new version of NumXL – 1.59 Tucson Along with numerous fixes, NumXL 1.59 supports 64-bit version of Microsoft Excel 2010 and 2013, which will make it possible to analyze larger…

NumXL Tips & Tricks Newsletter

* You can unsubscribe anytime.