Biomarker definitions for preclinical Alzheimer's disease (AD) have identified individuals with neurodegeneration (ND+) without β-amyloidosis (Aβ-) and labeled them with suspected non-AD ...pathophysiology (SNAP). We evaluated Apolipoprotein E (APOE) ε2 and ε4 allele frequencies across biomarker definitions-Aβ-/ND- (n = 268), Aβ+/ND- (n = 236), Aβ-/ND+ or SNAP (n = 78), Aβ+/ND+ (n = 204)-hypothesizing that SNAP would have an APOE profile comparable to Aβ-/ND-. Using AD Neuroimaging Initiative data (n = 786, 72±7 years, 48% female), amyloid status (Aβ+ or Aβ-) was defined by cerebrospinal fluid (CSF) Aβ-42 levels, and neurodegeneration status (ND+ or ND-) was defined by hippocampal volume from MRI. Binary logistic regression related biomarker status to APOE ε2 and ε4 allele carrier status, adjusting for age, sex, education, and cognitive diagnosis. Compared to the biomarker negative (Aβ-/ND-) participants, higher proportions of ε4 and lower proportions of ε2 carriers were observed among Aβ+/ND- (ε4: OR = 6.23, p<0.001; ε2: OR = 0.53, p = 0.03) and Aβ+/ND+ participants (ε4: OR = 12.07, p<0.001; ε2: OR = 0.29, p = 0.004). SNAP participants were statistically comparable to biomarker negative participants (p-values>0.30). In supplemental analyses, comparable results were observed when coding SNAP using amyloid imaging and when using CSF tau levels. In contrast to APOE, a polygenic risk score for AD that excluded APOE did not show an association with amyloidosis or neurodegeneration (p-values>0.15), but did show an association with SNAP defined using CSF tau (β = 0.004, p = 0.02). Thus, in a population with low levels of cerebrovascular disease and a lower prevalence of SNAP than the general population, APOE and known genetic drivers of AD do not appear to contribute to the neurodegeneration observed in SNAP. Additional work in population based samples is needed to better elucidate the genetic contributors to various etiological drivers of SNAP.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Forecasting export growth can be challenging. Export growth depends heavily on demand from foreign countries, which is difficult to directly measure. In practice, forecasters usually approximate ...strength in foreign demand through growth in foreign gross domestic product. But this approach has two problems. First, GDP data are released with a significant delay-for most countries, one to two quarters. Second, the quality of foreign GDP data varies. In some developing economies, GDP is poorly measured and thus may not be helpful in gauging those economies' true incomes (Johnson and others 2009; Deaton and Heston 2010).Recent research suggests nighttime lights data from satellites may be able to overcome both of these challenges, making them potentially useful in forecasting exports. Henderson and others (2012) show nighttime lights are useful in measuring GDP, as the amount of light in a given area is positively correlated with income in that area. In addition, satellite data are likely more reliable than countries' published measures. Furthermore, recent improvements in satellite technology have made satellite data available at higher frequencies than GDP data: monthly satellite data have been available since 2012, and daily data have been available since 2017. The increased frequency of these new data suggest nighttime lights could improve export forecasting based on foreign GDP. However, to the best of our knowledge, these data have not yet been tested in forecasting U.S. exports.In this analysis, we use nighttime lights data to forecast currentquarter U.S. export growth. We focus on current-quarter forecasts because a better estimate of current exports will establish a base for forecasting future exports. We find nighttime lights data are helpful overall in forecasting current-quarter U.S. export growth, largely due to more frequent data. In particular, we find that using monthly nighttime lights data generates a smaller forecast error than using quarterly foreign GDP When using quarterly data for both lights and foreign GDP, however, GDP data outperform lights data.Section I introduces the nighttime lights data from satellites and shows the relationship between the nighttime lights index and U.S. exports. Section II evaluates the performance of the lights data in forecasting U.S. exports.
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CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The financial crisis and Great Recession led to dramatic shifts in U.S. monetary policy over the past decade, with potential implications for inflation expectations. Prior to the crisis, inflation ...expectations were well-anchored. But during the crisis and recovery, the Federal Reserve turned to new policies such as large-scale asset purchases (LSAPs). In addition, the Federal Open Market Committee adopted a formal inflation target in 2012, with the stated goal of keeping longer-term inflation expectations stable. Did inflation expectations remain anchored during this period of unconventional policy?
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Dostopno za:
CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Among married and cohabiting couples, the percentage of female respondents has increased substantially in the PSID (Panel Study of Income Dynamics) from 9% in 1968 to 60% in 2015. This shift in ...gender composition has taken place despite a formal policy that historically designated male heads of household as respondents. We use this shift as a case study to explore which characteristics are associated with women responding to the PSID and how different respondent gender compositions may affect data quality. First, we find that women are increasingly less likely to respond as their husband’s income increases or if their husband is highly educated. Women are more likely to respond if they are more educated than their husband. {{p}} Second, we find that male respondents tend to report incomes about $5,000 higher than female respondents. Had the gender composition of respondents been closer to 50/50, average household income would have been reduced by as much as $2,500. Our research provides important insights into the quality of survey data and the changing role of women in households.
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