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The information-free event hypothesis associated with index additions has been very well documented in the finance literature. Most studies confirm that index addition conveys positive information about the future prospect of firms recently added to an index. However, this may not be the case for REITs, which are considered to have higher informational efficiency due to the transparent nature of their balance sheet. Using a sample of 108 additions to the S&P REIT Index over a period of 2000–2011, we test this hypothesis using analyst dividend forecasts. Our results are different from those found by similar studies in finance for non-REIT stocks. In most of the cases and consistent with our a priori expectations, the findings suggest that index addition announcement may not reveal much information beyond what is available from a REIT’s balance sheet. Specifically, our results suggest different responses of the analysts to the index announcement depending upon the type of revision to the dividend forecast. For positive revised estimates, the announcement does not seem to add any new information to the analysts. However, for the two other scenarios, i.e. negative revised estimates and no revision to the estimates, the results show some evidence of information bias. Thus, we see an asymmetric response depending on the type of revision made by the analyst. However, when we look at the longer time horizon between the forecasts, we find no influence of the index addition news for any of the cases analysed. Further, our results are robust to using EPS as a measure of analyst forecast as well. [ABSTRACT FROM PUBLISHER]

This study looks at the relationship between past returns and trading volume, specifically at year-end and tries to explain the trading motive underlying it. To be specific, we examine the relationship between the direction of past price changes and abnormal turnover. Results indicate that winners tend to have higher abnormal turnover rate than losers in a regular month (February to November). However, in December, as predicted by the tax-motivated trading hypothesis, the difference of trading turnovers between winners and losers generally is not statistically significant. Based on sub-periods, we find that before 1994, winners generally are significantly traded more in January than the losers. These findings indicate that overall for REITs, past price changes affect trading through both tax and non-tax motives. [ABSTRACT FROM PUBLISHER]

Using a sample of 58 Equity Real Estate Investment Trusts (EREITs) with geographic area specialization from 1994 to 2006, this study examines if EREITs concentrating their investment geographically could be able to generate abnormal returns due to home expertise. Based on the risk adjustment by Carhart's (1997) four-factor model, only REITs with geographical concentration in the Mideast and Northeast generate abnormal returns during the sample time period. However, with the robustness check, the abnormal return disappears. This paper therefore cautions the biased findings due to model misspecification problem and suggests that the REIT sector is generally functioning in an efficient fashion. [ABSTRACT FROM PUBLISHER]

Objectives: To evaluate the diagnostic performance of different mathematical models and different b-value ranges of diffusion-weighted imaging (DWI) in peripheral zone prostate cancer (PZ PCa) detection. Methods: Fifty-six patients with histologically proven PZ PCa who underwent DWI-magnetic resonance imaging (MRI) using 21 b-values (0–4500 s/mm2) were included. The mean signal intensities of the regions of interest (ROIs) placed in benign PZs and cancerous tissues on DWI images were fitted using mono-exponential, bi-exponential, stretched-exponential, and kurtosis models. The b-values were divided into four ranges: 0–1000, 0–2000, 0–3200, and 0–4500 s/mm2, grouped as A, B, C, and D, respectively. ADC, , D*, f, DDC, α, Dapp, and Kapp were estimated for each group. The adjusted coefficient of determination (R2) was calculated to measure goodness-of-fit. Receiver operating characteristic curve analysis was performed to evaluate the diagnostic performance of the parameters. Results: All parameters except D* showed significant differences between cancerous tissues and benign PZs in each group. The area under the curve values (AUCs) of ADC were comparable in groups C and D (p = 0.980) and were significantly higher than those in groups A and B (p< 0.05 for all). The AUCs of ADC and Kapp in groups B and C were similar (p = 0.07 and p = 0.954), and were significantly higher than the other parameters (p< 0.001 for all). The AUCs of ADC in group D was slightly higher than Kapp (p = 0.002), and both were significantly higher than the other parameters (p< 0.001 for all). Conclusions: ADC derived from conventional mono-exponential high b-value (3200 s/mm2) models is an optimal parameter for PZ PCa detection. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this prospective study was to assess the clinical utility of generalized autocalibrating partial parallel acquisition (GRAPPA)-accelerated readout-segmented echo-planar imaging (rs-EPI) DWI and compare it with standard single-shot EPI ( ss-EPI) DWI in visualization of the prostate during 3-T MRI., Subjects and Methods: One hundred sixteen consecutively registered patients (mean age, 63.5 years; range 24-93 years) underwent 3-T MRI that included rs-EPI DWI and standard ss-EPI DWI with identical FOVs, slices, acceleration factors, b values, and image postprocessing procedure. The datasets were independently evaluated by two blinded radiologists. Images were evaluated for sharpness, anatomic distortion, imaging contrast, lesion conspicuity, detailed anatomic visualization, and overall image quality on a 5-point Likert scale (1, nondiagnostic; 5, excellent)., Results: The kappa values were 0.73 for image sharpness, 0.71 for anatomic distortion, 0.54 for imaging contrast, 0.56 for lesion conspicuity, 0.61 for detailed anatomic visualization, and 0.63 for overall image quality (all p < 0.05), indicating moderate to substantial agreement between the two observers. The mean Likert scores for standard ss-EPI and rs-EPI were as follows: image sharpness, 2.9 and 4.6; distortion level, 2.8 and 4.4; contrast, 3.1 and 3.8; lesion conspicuity, 3.0 and 4.0; structure, 3.1 and 4.2; and overall image quality, 3.1 and 4.2. The rs-EPI DWI sequence was associated with significantly better image quality and fewer susceptibility artifacts than was ss-EPI (all p < 0.05). The rs-EPI sequence was considered better overall in 90% of cases., Conclusion: The technique of rs-EPI DWI combined with GRAPPA enables robust prostate imaging with high image quality and may provide great benefit in routine clinical practice.