Standard Deviation Drop Research Articles

Macroeconomic effects of fiscal rules for a commodity-exporting economy: avoiding procyclical bias in Kazakhstan

ABSTRACT This paper investigates the macroeconomic consequences of an alternative fiscal rule in the context of commodity price shocks for a commodity-exporting country. We build a DSGE model to explain the business cycle in an oil-exporting economy, estimated using macroeconomic data from Kazakhstan. Our results demonstrate that when fiscal policy is procyclical in response to a transitory negative oil price shock, and if a majority of households are non-Ricardian, then a one standard deviation drop in oil prices causes an output decline of about 0.19%. In contrast, if the fiscal policy is countercyclical and conducted according to the structural balance fiscal rule, output increases by about 0.13% in response to the same shock. We also report that countercyclical fiscal policy is robustly effective when the monetary policy is characterized by its active inflation stabilization framework.

Euro-area business confidence and COVID-19

ABSTRACT I study the effects of the COVID-19 pandemic on business confidence in 11 Euro area countries and its impact on economic activity. To obtain causal effects, I instrument business confidence with domestic household confidence as well as household confidence in neighboring countries. I find evidence suggesting that the confidence channel was a sizable component to the economic transmission of COVID-19. A one standard deviation drop in business confidence leads to between 5–6 and 9% fall in economic activity in the industrial and wholesale and retail trade sectors, respectively. These results highlight the importance of managing confidence and expectations in crisis episodes.

Mobile internet adoption in West Africa

Mobile broadband internet is the main technology through which individuals access the internet in developing countries. Understanding the barriers to broadband adoption is thus a priority in designing policies aiming to expand access and close the digital divide across socioeconomic groups and territories. This paper exploits data from harmonized household expenditure surveys in seven countries in West Africa in 2018/19—a subregion with one of the lowest levels of mobile internet penetration in the world—to identify the main factors that limit mobile broadband internet adoption. Results show that low levels of household consumption and the price of mobile services are two key constraints. A one standard deviation increase in household expenditure, about US$65 per capita per month, is associated with a 6.5% point rise in the probability of adoption, while a one standard deviation drop in the price of mobile internet services (as a share of per capita household expenditure), about 5.5% points, raises the probability of adoption by 2.4% points. Other determinants include demographic characteristics (sex, age, language, urban location), socioeconomic features (educational attainment, sector of employment), and other factors linked to policy (access to electricity, ownership of assets, alternative means of internet access). Results are robust to specifications focusing only on areas with mobile internet coverage (3G).

Mobile Internet Adoption in West Africa

Mobile broadband internet is the main technology through which individuals access the internet in developing countries. Understanding the barriers to broadband adoption is thus a priority in designing policies aiming to expand access and close the digital divide across socioeconomic groups and territories. This paper exploits data from harmonized household expenditure surveys in seven countries in West Africa in 2018/19 — a subregion with one of the lowest levels of mobile internet penetration in the world — to identify the main factors that limit mobile broadband internet adoption. Results show that low levels of household consumption and prices of services are two key constraints. One standard deviation increase in household expenditure, about US$65 per capita per month, is associated with a 6.5 percentage point rise in the probability of adoption, while one standard deviation drop in the price of mobile internet services, about US$3.60, increases the probability of adoption by 2.4 percentage points. Other determinants include demographic characteristics (sex, age, language, urban location), socioeconomic features (educational attainment, sector of employment), and other factors linked to policy (access to electricity, ownership of assets, alternative means of internet access). Results are robust to specifications focusing only in areas with mobile internet coverage (3G).

Euro Area Business Confidence and COVID-19

I study the effects of the Covid-19 pandemic on business confidence in 11 Euro area countries and its consequent impact on economic activity. To obtain causal effects, I instrument business confidence with domestic household confidence as well as average household confidence in neighboring countries. I find evidence suggesting that the confidence and expectations channel was an important component to the economic transmission of Covid-19. A one standard deviation drop in business confidence leads to between 5-6 and 9 percent fall in economic activity in the industrial and wholesale and retail trade sectors respectively. These results highlight the importance of managing confidence and expectations in crises episodes.

Economic Preferences and Obesity: Evidence from a Clinical Lab-in-Field Experiment

We study economic decision-making of 284 people with obesity and pre-diabetes who participated in a 6-months randomised controlled trial to control weight and prevent diabetes. To elicit preferences, we use incentive-compatible experimental tasks that participants completed during their medical screening examination. We find that, on average, participants are risk averse, show no evidence of present bias, and have impatience levels comparable to healthy samples described in the international literature. Variations in present bias and impatience are not significantly associated with variations in markers of obesity. But we find a significant negative association between risk tolerance and BMI and other markers of obesity for women. A 1 standard deviation increase in risk tolerance is associated with a 0.2 standard deviation drop in BMI and waist circumference. Impatience moderates the link between risk tolerance and obesity. We replicate the key finding of interaction effects between risk and time preferences using survey data from a nationally representative sample of 6,281 Australians with similar characteristics. Deviating markedly from the literature, we conclude that risk tolerance brings benefits for health outcomes if combined with patience in this understudied but highly policy-relevant population.

Motion Compensated Ultrasound Imaging Allows Thermometry and Image Guided Drug Delivery Monitoring from Echogenic Liposomes.

Ultrasound imaging is widely used both for cancer diagnosis and to assess therapeutic success, but due to its weak tissue contrast and the short half-life of commercially available contrast agents, it is currently not practical for assessing motion compensated contrast-enhanced tumor imaging, or for determining time-resolved absolute tumor temperature while simultaneously reporting on drug delivery. The objectives of this study were to: 1) develop echogenic heat sensitive liposomes (E-LTSL) and non-thermosensitive liposomes (E-NTSL) to enhance half-life of contrast agents, and 2) measure motion compensated temperature induced state changes in acoustic impedance and Laplace pressure of liposomes to monitor temperature and doxorubicin (Dox) delivery to tumors. LTSL and NTSL containing Dox were co-loaded with an US contrast agent (perfluoropentane, PFP) using a one-step sonoporation method to create E-LTSL and E-NTSL. To determine temperature induced intensity variation with respect to the state change of E-LTSL and E-NTSL in mouse colon tumors, cine acquisition of 20 frames/second for about 20 min (or until wash out) at temperatures of 42°C, 39.5°C, and 37°C was performed. A rigid rotation and translation was applied to each of the “key frames” to adjust for any gross motion that arose due to motion of the animal or the transducer. To evaluate the correlation between ultrasound (US) intensity variation and Dox release at various temperatures, treatment (5 mg Dox/kg) was administered via a tail vein once tumors reached a size of 300-400 mm3, and mean intensity within regions of interest (ROIs) defined for each sample was computed over the collected frames and normalized in the range of [0,1]. When the motion compensation technique was applied, a > 2-fold drop in standard deviation in mean image intensity of tumor was observed, enabling a more robust estimation of temporal variations in tumor temperatures for 15-20 min. due to state change of E-LTSL and E-NTSL. Consequently, a marked increase in peak intensity at 42°C compared to 37°C that corresponded with enhanced Dox delivery from E-LTSL in tumors was obtained. Our results suggest that echogenic liposomes provide a predictable change in tumor vascular contrast with temperature, and this property could be applicable to nanomonitoring of drug delivery in real time.

Differences in metastatic patterns in relation to time between primary surgery and first relapse from breast cancer suggest synchronized growth of dormant micrometastases.

A significant variation in the metastatic pattern among breast cancer patients exists. Clinical observations suggest that these differences are related to time to recurrence (TTR), thus suggesting a common systemic growth signal at the time of surgery. Our goal was to identify a marker for synchronized growth of micrometastases. To quantify the metastatic pattern at first relapse, 180 patients with metastatic breast cancer were studied. Standard deviation (SD) of lesions size and lesion number was calculated and served as a marker for variation. Patients with low SD (multiple/similar sized lesions) were assumed to have synchronized growth, whereas patients with high SD were assumed to have unsynchronized growth. Patients were grouped according to TTR; early (< 3 years-) or late (> 3 years- after surgery). In patients not receiving systemic adjuvant treatment, median SD was significantly lower in the early group (2.5 mm) compared with 6.4 mm in the late group (p = 0.005). In node negative patients, median SD was significantly lower in the early group (3.0 mm) when compared with the late group (5.7 mm, p = 0.02). An additional drop in SD was observed immediately after end of adjuvant endocrine therapy. Our results identify SD as a marker of synchronized metastatic growth in breast cancer. A metastatic phenotype characterized by multiple similar sized metastases, suggesting synchronized onset of growth of micrometastases was predominantly found in patients recurring early after surgery and was counteracted by adjuvant treatment. Systemic growth signals caused by surgery might be antagonized during the time window following surgery.

Estimated verbal IQ and the odds of problem gambling: a population-based study

The neurocognitive deficits and other correlates of problem gambling are also observable in individuals with lower cognitive abilities, suggesting that a low IQ may be a determinant of problem gambling. There has been very little research into this possibility. This study aimed to investigate the characteristics associated with problem gambling in a large population-based study in England, with a particular focus on IQ. The Adult Psychiatric Morbidity Survey (APMS) 2007 comprised detailed interviews with 7403 individuals living in private households in England. Problem gambling was ascertained using a questionnaire based on DSM-IV criteria. Verbal IQ was estimated using the National Adult Reading Test (NART). Confounders included socio-economic and demographic factors, common mental disorders, impulsivity, smoking, and hazardous drug and alcohol use. More than two-thirds of the population reported engaging in some form of gambling in the previous year, but problem gambling was rare [prevalence 0.7%, 95% confidence interval (CI) 0.5-1.0]. The odds of problem gambling doubled with each standard deviation drop in estimated verbal IQ [adjusted odds ratio (OR) 2.1, 95% CI 1.3-3.4, p = 0.003], after adjusting for other characteristics associated with problem gambling including age, sex, socio-economic factors, drug and alcohol dependence, smoking, impulsivity and common mental disorders. There was no strong relationship observed between IQ and non-problem gambling. People with lower IQs may be at a higher risk of problem gambling. Further work is required to replicate and study the mechanisms behind these findings, and may aid the understanding of problem gambling and inform preventative measures and interventions.

Clinical risk factors, bone density and fall history in the prediction of incident fracture among men and women

The FRAXtr algorithm uses clinical risk factors (CRF) and bone mineral density (BMD) to predict fracture risk but does not include falls history in the calculation. Using results from the Hertfordshire Cohort Study, we examined the relative contributions of CRFs, BMD and falls history to fracture prediction. We studied 2299 participants at a baseline clinic that included completion of a health questionnaire and anthropometric data. A mean of 5.5years later (range 2.9–8.8years) subjects completed a postal questionnaire detailing fall and fracture history. In a subset of 368 men and 407 women, bone densitometry was performed using a Hologic QDR 4500 instrument. There was a significantly increased risk of fracture in men and women with a previous fracture. A one standard deviation drop in femoral neck BMD was associated with a hazards ratio (HR) of incident fracture (adjusted for CRFs) of 1.92 (1.04–3.54) and 1.77 (1.16–2.71) in men and women respectively. A history of any fall since the age of 45years resulted in an unadjusted HR of fracture of 7.31 (3.78–14.14) and 8.56 (4.85–15.13) in men and women respectively. In a ROC curve analysis, the predictive capacity progressively increased as BMD and previous falls were added into an initial model using CRFs alone. Falls history is a further independent risk factor for fracture. Falls risk should be taken into consideration when assessing whether or not to commence medication for osteoporosis and should also alert the physician to the opportunity to target falls risk directly.

Patriotism in your portfolio

More patriotic countries have greater home bias in their equity selection. In a panel of World Values Surveys covering 53 countries, measures of patriotism are positively related to home bias measures after controlling for transaction barriers, diversification benefits, information, and familiarity. Within-country changes in patriotism vary with changes in the home bias. The results are robust to using ISSP measures of patriotism covering 24 countries and within-U.S. data from the Survey of Consumer Finances. Instrumenting patriotism with social variables uncorrelated with economic and political factors confirms that patriotism affects investment. The average country invests $18 to $30 billion more abroad (a 3% to 5% increase) with a one standard deviation drop in patriotism.

Land Distribution and International Agricultural Productivity

The unequal distribution of agricultural land is often cited as a source of inefficiency in agriculture. Previous cross‐country studies of agricultural productivity differences, though, have not considered land inequality. This article addresses this issue by using cross‐country data on inequality in operational holdings of agricultural land from Deininger and Squire (1998). In an estimation of an agricultural production function, the Gini coefficient for land holdings is found to have a significant negative relationship with productivity. This is consistent with the existence of heterogeneity in productivity by farm size within countries. A one standard deviation drop in the Gini coefficient implies an increase in productivity of 8.5%.

Inception of Turbulence in the Stokes Boundary Layer Over a Transpiring Wall

In this work, the onset of turbulence inside a rectangular chamber is investigated, with and without side-wall injection, in the presence of an oscillatory pressure gradient. Two techniques are used to define the transition from laminar to turbulent regimes: statistical analysis and flow visualization. Calibrated hot film anemometry and a computer data acquisition system are used to record and analyze acoustical flow data. Four classifications of flow regimes are reported: (a) laminar, (b) distorted laminar, (c) weakly turbulent, and (d) conditionally turbulent. Despite numerous attempts to promote turbulence, a fully turbulent flow does not develop at any of the driving frequencies tested. Statistical measurements reveal that a periodic drop in standard deviation of axial velocity fluctuations always occurs, indicating relaminarization within each cycle. Transition between flow regimes is assessed from the standard deviation of velocity data correlated as a function of the acoustic Reynolds number ReA. Under predominantly laminar conditions, the standard deviation is found to vary approximately with the square of the acoustic Reynolds number. Under turbulent conditions, the standard deviation becomes almost directly proportional to the acoustic Reynolds number. Inception of turbulence in the oscillatory flow with side-wall injection is found to be reproducible at the same critical value of ReA≅200.