Expectations and Investment

Using micro data from Duke University quarterly survey of Chief Financial Officers, we show that corporate investment plans as well as actual investment are well explained by CFOs’ expectations of earnings growth. The information in expectations data is not subsumed by traditional variables, such as Tobin’s Q or discount rates. We also show that errors in CFO expectations of earnings growth are predictable from past earnings and other data, pointing to extrapolative structure of expectations and suggesting that expectations may not be rational. This evidence, like earlier findings in finance, points to the usefulness of data on actual expectations for understanding economic behavior.Economic

Advances in the Antifungal Effects of Plant Essential Oils

Foods, agricultural by-products and medicinal plants are often contaminated by pathogenic fungi and mycotoxins. Pathogenic fungi not only lead to food deterioration, but also harm people’s health. The commonly used methods for detoxification include physical, chemical and biological methods. A large number of studies have shown that natural plant essential oils inhibit the growth of pathogenic fungi and the accumulation of mycotoxins and have good biodegradability, making them a promising environmental-friendly alternative to traditional synthetic fungicides. In this review, the classification and harm of common pathogenic fungi and mycotoxins, as well as the antifungal components and mechanisms of plant essential oils are introduced, and recent progress on plant essential oils in the control of pathogenic fungi and mycotoxins is summarized. This review provides a theoretical basis for the development and application of plant essential oils

Linear Phase Multi-Frequency Notch Filter via Quadratic Programming

Discrete-time notch filters can be divided into infinite impulse response (IIR) and finite impulse response (FIR) notch filters. Infinite impulse response notch filters are easy to design and implement but suffer from nonlinear phase characteristics and unacceptable startup transients. Finite impulse response filters on the other hand can be designed to have linear phase but require more coefficients to achieve narrow notch widths. Multiple frequency FIR notch filters that can effectively reject several selected spectral regions while providing high transmission at frequencies outside the rejected regions have applications in communication systems, radar systems and biomedical signal processing. A new multi-frequency notch filter is introduced that is based on quadratic programming. This notch filter has linear phase and has notch widths which can be made arbitrarily narrow. We compare the performance of our notch filter with three existing multi-frequency notch filters: the iteratively reweighted OMP scheme and the multiple exchange algorithm

100 years of rising corporate concentration

We collect data on the size distribution of all U.S. corporate businesses for 100 years. We document that corporate concentration (e.g., asset share or sales share of the top 1%) has increased persistently over the past century. Rising concentration was stronger in manufacturing and mining before the 1970s, and stronger in services, retail, and wholesale after the 1970s. Furthermore, rising concentration in an industry aligns closely with investment intensity in research and development and information technology. Industries with higher increases in concentration also exhibit higher output growth. The long-run trends of rising corporate concentration indicate increasingly stronger economies of scale

Corporate flexibility in a time of crisis

We use the COVID shock to study the direct and interactive effects of several forms of corporate flexibility on short- and long-term real business plans. We find that i) workplace flexibility, namely the ability for employees to work remotely, plays a central role in determining firms’ employment plans during the health crisis; ii) investment flexibility allows firms to increase or decrease capital spending based on their business prospects in the crisis, with effects shaped by workplace flexibility; and iii) financial flexibility contributes to stronger employment and investment, in particular when fixed costs are high. While the role of workplace flexibility is new to the COVID crisis, CFOs expect lasting effects for years to come: high workplace flexibility firms foresee continuation of remote work, stronger employment recovery, and shifting away from traditional capital investment, whereas low workplace flexibility firms rely more on automation to replace labor

Impact of radiologist experience on medical image quality perception

Low quality medical images can lead to inaccurate interpretation and diagnosis. Therefore, it is important to understand radiologists' perception of distortions in visual content. In this study, 12 radiologists with different degrees of experience scored MRI images of varying levels of quality. Statistical analyses were conducted to reveal the influence of the radiologists' experience on their perception of image quality. In scoring images of joints, brain and liver, the highly experienced radiologists gave significantly higher scores than less experienced radiologists. In scoring images of fetus and spine, there were no significant differences in scores between groups with different degrees of experience. No radiologists had expertise in breast images, and their experience in other anatomical areas did not significantly affect scoring of breast images. Overall, highly experienced radiologists gave higher scores for images with edge ghosting, plain ghosting or white noise than radiologists with less experience. The findings will provide a reference for determining or improving image quality standards in clinical practice