Towards Optimal Discrete Online Hashing with Balanced Similarity

When facing large-scale image datasets, online hashing serves as a promising solution for online retrieval and prediction tasks. It encodes the online streaming data into compact binary codes, and simultaneously updates the hash functions to renew codes of the existing dataset. To this end, the existing methods update hash functions solely based on the new data batch, without investigating the correlation between such new data and the existing dataset. In addition, existing works update the hash functions using a relaxation process in its corresponding approximated continuous space. And it remains as an open problem to directly apply discrete optimizations in online hashing. In this paper, we propose a novel supervised online hashing method, termed Balanced Similarity for Online Discrete Hashing (BSODH), to solve the above problems in a unified framework. BSODH employs a well-designed hashing algorithm to preserve the similarity between the streaming data and the existing dataset via an asymmetric graph regularization. We further identify the "data-imbalance" problem brought by the constructed asymmetric graph, which restricts the application of discrete optimization in our problem. Therefore, a novel balanced similarity is further proposed, which uses two equilibrium factors to balance the similar and dissimilar weights and eventually enables the usage of discrete optimizations. Extensive experiments conducted on three widely-used benchmarks demonstrate the advantages of the proposed method over the state-of-the-art methods.Comment: 8 pages, 11 figures, conferenc

Nominal Rigidity and Some New Evidence on the New Keynesian Theory of the Output-Inflation Tradeoff

This paper develops a series of tests to check whether the New Keynesian nominal rigidity hypothesis on the output-inflation tradeoff withstands new evidence. In so doing, I summarize and evaluate different estimation methods that have been applied in the literature to address this hypothesis. Both cross-country and over-time variations in the output-inflation tradeoff are checked with the tests that differentiate the effects on the tradeoff that are attributable to nominal rigidity (the New Keynesian argument) from those ascribable to variance in nominal growth (the alternative new classical explanation). I find that in line with the New Keynesian hypothesis, nominal rigidity is an important determinant of the tradeoff. Given less rigid prices in high-inflation environments, changes in nominal demand are transmitted to quicker and larger movements in prices and lead to smaller fluctuations in the real economy. The tradeoff between output and inflation is hence smaller

What Measures Chinese Monetary Policy?

This paper models the People’s Bank of China’s operating procedures in a two-stage vector autoregression model to search for a valid good policy indicator for Chinese monetary policy. The model disentangles endogenous components in changes in monetary policy that are driven either by demand for money or the liquidity management needs arising from foreign exchange purchases. There are four main findings. First, the PBC’s procedures appear to have changed over time, and hence no single indicator represents Chinese monetary policy well for the 2000-2013 time period. Second, its operating procedure is neither pure interest-rate targeting nor pure reserves targeting, but a mixture. Third, a set of indicators all contain information about the policy stance. It is hence preferred to use a composite measure to measure Chinese monetary policy. Finally, we construct a new composite indicator of the overall policy stance, consistent with our model. A comparison with several existing measurement approaches suggests that the composite indices, rather than individual indicators, perform better in measuring Chinese monetary policy

What Measures Chinese Monetary Policy?

This paper models the People’s Bank of China’s operating procedures in a two-stage vector autoregression model to search for a valid good policy indicator for Chinese monetary policy. The model disentangles endogenous components in changes in monetary policy that are driven either by demand for money or the liquidity management needs arising from foreign exchange purchases. There are four main findings. First, the PBC’s procedures appear to have changed over time, and hence no single indicator represents Chinese monetary policy well for the 2000-2013 time period. Second, its operating procedure is neither pure interest-rate targeting nor pure reserves targeting, but a mixture. Third, a set of indicators all contain information about the policy stance. It is hence preferred to use a composite measure to measure Chinese monetary policy. Finally, we construct a new composite indicator of the overall policy stance, consistent with our model. A comparison with several existing measurement approaches suggests that the composite indices, rather than individual indicators, perform better in measuring Chinese monetary policy

Requiem for the Interest-Rate Controls in China

This paper reviews the retail interest-rate-control deregulation in China over the 1993-2015 period and provides a preliminary assessment of the PBC's replacement monetary framework. I show that the interest-rate controls triggered the development of deposit substitutes that banks used to circumvent the restrictions, which in turn drove deposits out of commercial banks.This gave rise to concerns about deterioration of bank profits and build-up of financial frangibility, which have pushed up the PBC's deregulation acceleration over the post-2012 period. I quantify the distortionary effects of these controls: disintermediation, a rising shadow banking system and financial repression. Despite the official lift-off of the controls, the retail interest rates are still subject to the PBC’s window guidance and other pricing mechanism guidance. The interest-rate corridor does not function well in confining money market rates. This suggests that the PBC adopt a target money market rate system

Review over Empirical Evidence on Real Effects of Monetary Policy

This paper reviews and discusses the empirical literature on the impact of monetary policy on output. We focus on the evolution of methods that these studies have applied and demonstrate the established fact that monetary policy has significant impact on output. Throughout the review, we particularly highlight two problems in estimating the effects of monetary policy: the problem of how to measure monetary policy and the identification problem

A Narrative Indicator of Monetary Conditions in China

In this paper, we apply the narrative approach, studying the PBC's historical records, to infer policy-makers' intentions and thereby build a time series of monetary policy indicator. We show that our narrative policy indicator is informative about economic activity. Changes in it reflect the PBC's responses to its perceptions of economic conditions. It is a good indicator of monetary policy actions. Finally, we show that compared to monetary aggregates, changes in interest rates and the required reserve ratio are more associated with changes in monetary policy, as measured by our narrative indicator, but only to a limited degree. None of them alone can be a good proxy of policy indicator

Nominal Rigidity and Some New Evidence on the New Keynesian Theory of the Output-Inflation Tradeoff

This paper develops a series of tests to check whether the New Keynesian nominal rigidity hypothesis on the output-inflation tradeoff withstands new evidence. In so doing, I summarize and evaluate different estimation methods that have been applied in the literature to address this hypothesis. Both cross-country and over-time variations in the output-inflation tradeoff are checked with the tests that differentiate the effects on the tradeoff that are attributable to nominal rigidity (the New Keynesian argument) from those ascribable to variance in nominal growth (the alternative new classical explanation). I find that in line with the New Keynesian hypothesis, nominal rigidity is an important determinant of the tradeoff. Given less rigid prices in high-inflation environments, changes in nominal demand are transmitted to quicker and larger movements in prices and lead to smaller fluctuations in the real economy. The tradeoff between output and inflation is hence smaller