Evaluating House Price Forecasts

House prices, unlike stock prices, appear to be predictable with some degree of accuracy. We use an autoregressive process to model the time series behavior of a city-wide house price index, and then produce one-quarter ahead forecasts for individual properties. Better real estate decisions require forecasting models with desirable properties for prediction errors (PEs). We propose that managers use a battery of tests to compare PEs; in particular, non-parametric smoothing of the empirical distribution of PEs can add important information to statistics that focus on first and second moments. The decision-making framework is fitted with housing transactions from Dade County, Florida, from 1976 through the second quarter of 1997. PEs from two forecasting models, hedonic and repeat sales, show some departure from the desirable properties of any one-step-ahead forecast. Also, both show some informational inefficiency, but the hedonic is more efficient than the repeat. Nonparametric smoothing shows that the hedonic method dominates the repeat over an important range of PEs; thus, a case can be made that many risk-averse managers would prefer a forecast based on the hedonic method.

Bulletin 61 - Reading Aloud: War-Time Suggestions

https://thekeep.eiu.edu/eiu_bulletin/1161/thumbnail.jp

Hedonic pricing with redevelopment options: A new approach to estimating depreciation effects

The standard hedonic model of durable assets is a special case of a more general model that contains two additive terms: (1) use value of the existing hedonic vector and (2) the value of the option to reconfigure hedonic characteristics. One empirical implication is that the two parts of value are related: e.g., use value increases with interior area whereas option value decreases with “intensity,” the ratio of structure value divided by land value. Increases in building age reduce use value but increase option value. Data from Greenwich Connecticut indicate that intensity has the expected negative effect. Coefficients on building age are shown to be better measures of depreciation when intensity variables are included in the regression

Empirical estimation of the option premium for residential redevelopment

This paper presents and validates a novel empirical approach for measuring the value of the option to redevelop using a standard hedonic dataset. Our analysis generalizes the standard hedonic model to account for the option value of reconfiguring hedonic characteristics. We test this model with over 162,000 real estate transactions in 53 towns in Connecticut between 1994 and 2007 by adding a non-linear intensity variable, which increases with the aggregate value of structure and decreases with land value. A conservative estimate is that about 20% of towns have significantly positive option value, with a mean value of 29–34% for properties most similar to vacant land. Multiple tests across towns support predictions of real options theory. Positive option value towns have higher house price volatility and estimated option value varies positively with price volatility, a finding inconsistent with NPV theory. We also find positive association between option value and drift in house prices and a U-shape relation with house price adjusted for structural characteristics. Higher property taxes reduce the value of option to redevelop

Randomized clinical trial of the effects of screening and brief intervention for illicit drug use: the Life Shift/Shift Gears study.

BackgroundAlthough screening, brief intervention, and referral to treatment (SBIRT) has shown promise for alcohol use, relatively little is known about its effectiveness for adult illicit drug use. This randomized controlled trial assessed the effectiveness of the SBIRT approach for outcomes related to drug use among patients visiting trauma and emergency departments (EDs) at two large, urban hospitals.MethodsA total of 700 ED patients who admitted using illegal drugs in the past 30 days were recruited, consented, provided baseline measures of substance use and related problems measured with the Addiction Severity Index-Lite (ASI-Lite), and then randomized to the Life Shift SBIRT intervention or to an attention-placebo control group focusing on driving and traffic safety (Shift Gears). Both groups received a level of motivational intervention matched to their condition and risk level by trained paraprofessional health educators. Separate measurement technicians conducted face-to-face follow-ups at 6 months post-intervention and collected hair samples to confirm reports of abstinence from drug use. The primary outcome measure of the study was past 30-day drug abstinence at 6 months post-intervention, as self-reported on the ASI-Lite.ResultsOf 700 participants, 292 (42%) completed follow-up. There were no significant differences in self-reported abstinence (12.5% vs. 12.0% , p = 0.88) for Life Shift and Shift Gears groups, respectively. When results of hair analyses were applied, the abstinence rate was 7 percent for Life Shift and 2 percent for Shift Gears (p = .074). In an analysis in which results were imputed (n = 694), there was no significant difference in the ASI-Lite drug use composite scores (Life Shift +0.005 vs. Shift Gears +0.017, p = 0.12).ConclusionsIn this randomized controlled trial, there was no evidence of effectiveness of SBIRT on the primary drug use outcome.Trial registrationClinicalTrials.gov NCT01683227

Seasonal Movements of Chinook Salmon in Lake Michigan Based on Tag Recoveries from Recreational Fisheries and Catch Rates in Gill‐Net Assessments

There are no specific studies of the movements of introduced Chinook salmon Oncorhynchus tshawytscha in Lake Michigan, despite the need for such information for population assessments and stocking allocations. We investigated the seasonal distribution of hatchery‐reared Chinook salmon between May and September based on fishery‐dependent (recoveries from recreational fisheries of fish marked with coded wire tags [CWTs]) and fishery‐independent sources (catches in assessment gill‐net surveys). We modeled recoveries by fishing trips in Michigan waters of Lake Michigan to estimate spatially and temporally explicit abundance indices using generalized linear models (GLMs) and accounted for the efficiency among recovery sources (charter boat captain reports, creel clerk interviews, and headhunter collections of CWT samples from charter boat and non‐charter boat catches). Recovery levels varied among areas, months, years, and recovery sources, and distribution among areas also varied by month. We used CWT data with lakewide geographical coverage and evaluated the distributions of the absolute numbers of coded‐wire‐tagged fish recovered in Michigan and Wisconsin waters of Lake Michigan from all possible recovery sources. From both analyses we found that the distribution of Chinook salmon varied seasonally, with displacements from southern areas toward the north from May through summer, from inshore to offshore areas toward the west during summer, and movement back east in the fall. For the analysis of Chinook salmon catch rates in gill‐net assessments, we used GLMs to compare levels among months, statistical districts, years, nearshore and offshore areas, and different depths. The temporal and spatial trends were similar to those from the CWT analyses, and the distribution shifted toward deeper waters in July and August. Movement patterns coincided with favorable temperature and prey distribution and were consistent with those exhibited by the Pacific Ocean Chinook salmon population from which the Lake Michigan population originated. Seasonal changes in Chinook salmon distribution influence recreational fisheries, and stocking strategies should consider the influences of movement patterns on fishing opportunities in Lake Michigan.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142273/1/tafs0736.pd

Centerscope

Centerscope, formerly Scope, was published by the Boston University Medical Center "to communicate the concern of the Medical Center for the development and maintenance of improved health care in contemporary society.

Social learning and amygdala disruptions in Nf1 mice are rescued by blocking p21-activated kinase

Children with Neurofibromatosis type 1 (NF1) are increasingly recognized to have high prevalence of social difficulties and autism spectrum disorders (ASD). We demonstrated selective social learning deficit in mice with deletion of a single Nf1 gene (Nf1+/−), along with greater activation of mitogen activated protein kinase pathway in neurons from amygdala and frontal cortex, structures relevant to social behaviors. The Nf1+/− mice showed aberrant amygdala glutamate/GABA neurotransmissiondeficits in long-term potentiationand specific disruptions in expression of two proteins associated with glutamate and GABA neurotransmission: a disintegrin and metalloprotease domain 22 (ADAM22) and heat shock protein 70 (HSP70), respectively. All of these amygdala disruptions were normalized by co-deletion of p21 protein-activated kinase (Pak1) gene. We also rescued the social behavior deficits in Nf1+/− mice with pharmacological blockade of Pak1 directly in the amygdala. These findings provide novel insights and therapeutic targets for NF1 and ASD patients

A Case Study of Convectively Sourced Water Vapor Observed in the Overworld Stratosphere over the United States

On 27 August 2013, during the Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys field mission, NASA's ER2 research aircraft encountered a region of enhanced water vapor, extending over a depth of approximately 2 km and a minimum areal extent of 20,000 km(exp 2) in the stratosphere (375 K to 415 K potential temperature), south of the Great Lakes (42N, 90W). Water vapor mixing ratios in this plume, measured by the Harvard Water Vapor instrument, constitute the highest values recorded in situ at these potential temperatures and latitudes. An analysis of geostationary satellite imagery in combination with trajectory calculations links this water vapor enhancement to its source, a deep tropopausepenetrating convective storm system that developed over Minnesota 20 h prior to the aircraft plume encounter. High resolution, groundbased radar data reveal that this system was composed of multiple individual storms, each with convective turrets that extended to a maximum of ~4 km above the tropopause level for several hours. In situ water vapor data show that this storm system irreversibly delivered between 6.6 kt and 13.5 kt of water to the stratosphere. This constitutes a 2025% increase in water vapor abundance in a column extending from 115 hP to 70 hPa over the plume area. Both in situ and satellite climatologies show a high frequency of localized water vapor enhancements over the central U.S. in summer, suggesting that deep convection can contribute to the stratospheric water budget over this region and season

The medical student

The Medical Student was published from 1888-1921 by the students of Boston University School of Medicine