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Background: Computational models based on artificial intelligence (AI) are increasingly used to diagnose malignant breast le-sions. However, assessment from radiologic images of the specific pathologic lesion subtypes, as detailed in the results of biopsy procedures, remains a challenge. Purpose: To develop an AI-based model to identify breast lesion subtypes with mammograms and linked electronic health records labeled with histopathologic information. Materials and Methods:In this retrospective study, 26 569 images were collected in 9234 women who underwent digital mammog-raphy to pretrain the algorithms. The training data included individuals who had at least 1 year of clinical and imaging history followed by biopsy-based histopathologic diagnosis from March 2013 to November 2018. A model that combined convolutional neural networks with supervised learning algorithms was independently trained to make breast lesion predictions with data from 2120 women in Israel and 1642 women in the United States. Results were reported using the area under the receiver operating characteristic curve (AUC) with the 95% DeLong approach to estimate CIs. Significance was tested with bootstrapping.Results: The Israeli model was validated in 456 women and tested in 441 women (mean age, 51 years 6 11 [SD]). The U.S. model was validated in 350 women and tested in 344 women (mean age, 60 years 6 12). For predicting malignancy in the test sets (con-sisting of 220 Israeli patient examinations and 126 U.S. patient examinations with ductal carcinoma in situ or invasive cancer), the algorithms obtained an AUC of 0.88 (95% CI: 0.85, 0.91) and 0.80 (95% CI: 0.74, 0.85) for Israeli and U.S. patients, respectively (P= .006). These results may not hold for other cohorts of patients, and generalizability across populations should be further investigated. Conclusion: The results offer supporting evidence that artificial intelligence applied to clinical and mammographic images can identify breast lesion subtypes when the data are sufficiently large, which may help assess diagnostic workflow and reduce biopsy sampling errors.

Pneumoperitoneum (free air in the peritoneal cavity) is a rare condition that can be life threatening and require emergency surgery. It can be detected in chest X-ray but there are some challenges associated to this detection, such as small amounts of air that may be missed by a radiologist, or pseudo-pneumoperitoneum (air in the abdomen that may look like pneumoperitoneum). In this work, we propose using an ensemble of deep learning models trained on different subsets of data to boost the classification and generalization performance of the model as well as hard-negative mining to mitigate the effect of pseudo-pneumoperitoneum. We demonstrate superior performance when the model ensemble is utilized as well as good localization of the finding with multiple model explainability techniques.

Objective To conduct a systematic review identifying workplace interventions that mitigate physician burnout related to the digital environment including health information technologies (eg, electronic health records) and decision support systems) with or without the application of advanced analytics for clinical care. Materials and Methods Literature published from January 1, 2007 to June 3, 2020 was systematically reviewed from multiple databases and hand searches. Subgroup analysis identified relevant physician burnout studies with interventions examining digital tool burden, related workflow inefficiencies, and measures of burnout, stress, or job satisfaction in all practice settings. Results The search strategy identified 4806 citations of which 81 met inclusion criteria. Thirty-eight studies reported interventions to decrease digital tool burden. Sixty-eight percent of these studies reported improvement in burnout and/or its proxy measures. Burnout was decreased by interventions that optimized technologies (primarily electronic health records), provided training, reduced documentation and task time, expanded the care team, and leveraged quality improvement processes in workflows. Discussion The contribution of digital tools to physician burnout can be mitigated by careful examination of usability, introducing technologies to save or optimize time, and applying quality improvement to workflows. Conclusion Physician burnout is not reduced by technology implementation but can be mitigated by technology and workflow optimization, training, team expansion, and careful consideration of factors affecting burnout, including specialty, practice setting, regulatory pressures, and how physicians spend their time.

We present a stacked weak lensing analysis of 27 richness selected galaxy clusters at $0.40 \leqslant z \leqslant 0.62$ in the CODEX survey. The fields were observed in 5 bands with the CFHT. We measure the stacked surface mass density profile with a $14��$ significance in the radial range $0.1 < R\ Mpc\ h^{-1} < 2.5$. The profile is well described by the halo model, with the main halo term following an NFW profile and including the off-centring effect. We select the background sample using a conservative colour-magnitude method to reduce the potential systematic errors and contamination by cluster member galaxies. We perform a Bayesian analysis for the stacked profile and constrain the best-fit NFW parameters $M_{200c} = 6.6^{+1.0}_{-0.8} \times 10^{14} h^{-1} M_{\odot}$ and $c_{200c} = 3.7^{+0.7}_{-0.6}$. The off-centring effect was modelled based on previous observational results found for redMaPPer SDSS clusters. Our constraints on $M_{200c}$ and $c_{200c}$ allow us to investigate the consistency with numerical predictions and select a concentration-mass relation to describe the high richness CODEX sample. Comparing our best-fit values for $M_{200c}$ and $c_{200c}$ with other observational surveys at different redshifts, we find no evidence for evolution in the concentration-mass relation, though it could be mitigated by particular selection functions. Similar to previous studies investigating the X-ray luminosity-mass relation, our data suggests a lower evolution than expected from self-similarity., 28 pages, 17 figures, submitted to MNRAS

The Intergenerational Reports have helped lengthen the horizon of public policy analysis in Australia, enabling governments to focus on the longer term implications of policy changes, particularly their fiscal implications. Nonetheless, it is important to note that the reports have examined fiscal sustainability from the Commonwealth's perspective, notwithstanding that fiscal sustainability is also an issue for the states and territories. Additionally, the reports have not incorporated contingent fiscal liabilities, notwithstanding their relevance to fiscal sustainability.

This lecture examines the lessons learnt from Australia's experience in the 1930s, and how these lessons have informed more recent economic policy decisions including the policy responses to the current global financial crisis. The lecture argues that the lessons learnt from the Great Depression have informed the macroeconomic frameworks of today. While Australia's policy frameworks of the 1930s were tragically ill equipped to cope with anything other than small, inconsequential macroeconomic or financial market shocks, the policy frameworks put in place in the modern era have rendered the economy much more resilient to such shocks.

This paper examines the evolution of Australian fiscal policy and the fiscal policy framework over the past quarter century. Following the early 1980s recession, a sustained fiscal consolidation saw the general government budget balance (for all levels of government) move from a deficit of 3 1/2 per cent of GDP in 1983-84 to a surplus of 1 3/4 per cent five years later in 1988-89. A severe recession in the early 1990s interrupted this process, and the budget returned to sizeable deficits which peaked at 4 3/4 per cent of GDP in 1992-93. The second half of the 1990s saw a repeat of the experience a decade earlier, with the budget returning to surplus in 1997-98. In contrast to the 1980s experience, however, the general government sector (for all levels of government) has recorded surpluses for the subsequent eight years to the present. The paper outlines Australia’s macroeconomic experience over this time and argues that there have been two significant medium-term factors motivating the extended periods of fiscal consolidation. The first factor, relevant since the mid 1980s, has been the large Australian current account deficits since that time, and the associated build-up of net foreign liabilities. The second factor, which entered the public debate more recently, is a desire to provide fiscal policy flexibility to respond to the ageing of the population and the projected rising public cost of health services-both influences that are likely to be of increasing importance over the next generation or so. The paper discusses the introduction and evolution of Australia’s medium-term fiscal framework which has been put in place to respond to these challenges.

The output gap is of central interest to policymakers. Being unobservable, however, its estimation is prone to error, particularly in real time. Errors result from revisions to the data and unavoidable end-point problems associated with the econometric techniques used to estimate it. This is the first study of the seriousness of these problems for Australia. Over a 28-year period, we obtain real-time output-gap estimates which are unbiased and highly correlated with final estimates derived with the latest data and the benefit of hindsight. We conclude that reasonably reliable output gap estimates can be obtained in real time.

Purpose To describe magnetic resonance (MR) imaging and MR cholangiopancreatography (MRCP) findings in gallbladder carcinoma, and to correlate these findings with available surgical and biopsy information. Methods Preoperative MR images (T1-weighted spin-echo, T2-weighted fast spin-echo, single shot fast spin-echo, and dynamic gadolinium-enhanced gradient echo) in 34 patients with gallbladder carcinoma were retrospectively reviewed for appearance of the primary neoplasm and for demonstration of hepatic, peritoneal, duodenal, and nodal involvement. Imaging findings were then compared with surgical findings (n = 19 patients) and histologic findings (n = 15 patients). Results Gallbladder carcinoma manifested at MR imaging as focal gallbladder wall thickening with an eccentric mass in 76% (26/34) of cases. The most common types of regional spread demonstrated were direct liver invasion in 91% (31/34), lymphadenopathy in 76% (26/34), and biliary tract invasion in 62% (21/34). Sensitivity for direct hepatic invasion was 100%, and was 92% for lymph node metastasis. Conclusion MRI and MRCP can provide information relevant to preoperative staging of gallbladder carcinoma.

The length of the transmission lags from monetary pblicy to output has been the subject of much research over the years, but there are serious problems in isolating the lags with any precision. This paper uses a simple model of Australian output to estimate the length of the lags, and then examines how attempts to grapple with the estimation problems might change the results. We estimate that output growth falls by about one-third of one per cent in both the first and second years after a one percentage point rise in the short-term real interest rate, and by about one-sixth of one per cent in the third year. This implies an average lag of about five or six quarters in monetary policy's impact on output growth. Each of these estimates is, however, subject to considerable uncertainty. We discuss the implications for policy of these relatively long and uncertain lags. Finally, we find no evidence that the average lag from monetary policy to output growth has become any shorter in the 1990s.

This paper explores the relationship between the terms of trade and inflation. It shows, both analytically and empirically, that the exchange rate response to a change in the terms of trade is crucial to the inflation outcome. It suggests the existence of a ‘threshold’ exchange rate response. Our best estimate is that (other things being equal) a rise in the terms of trade is inflationary if the associated rise in the real exchange rate is less than about 1/3-1/2 of the rise in the terms of trade. However, if appreciation of the real exchange rate is larger than this, the consequent fall in the domestic price of importables is large enough that the terms of trade rise reduces inflation, at least in the short run.

A risk-averse US investor adjusts the shares of a portfolio of short-term nominal domestic and foreign assets to maximize expected utility. The optimal strategy is to respond immediately to all new information which arrives weekly. We develop a model to estimate the cost of optimizing less frequently and find that it is generally very small. For example, if the investor adjusts portfolio shares every three months, an average expected utility loss of 0.16 per cent p.a. is incurred. Hence, slight opportunity costs of frequent optimization may outweigh the benefits. This result may help explain forward discount bias.

The resources boom, globalisation and other global economic forces have raised questions about whether employment and unemployment outcomes in regional Australia have become more unequal. This paper examines how the dispersion of unemployment across regions has changed over time. Our results show that unemployment dispersion has narrowed as the aggregate level of unemployment has declined. This relationship has not changed over the course of the current resources boom and is consistent with similar outcomes in the United States and the United Kingdom.

This paper presents detailed analysis of a very unusual event —a recent six-year period during which big excess returns were earned on the short-term interest-bearing assets of a small open economy: Australia. A risk premium does not explain the excess return. Rather than requiring a risk premium, market participants continually expected significant real depreciation of the Australian dollar, despite the fact that on average it appreciated in real terms. Our results may be a consequence of the foreign exchange market only gradually learning about the changed nature of the world capital market in the 1980s.

We find weak evidence of a stable relationship between the Australian real exchange rate and the terms of trade from 1969 to 1990. Since the float, the terms of trade and long real interest differentials together help to explain the real exchange rate. Our best estimates are that a real exchange rate appreciation of about 0.3 to 0.5 per cent is associated with a 1 per cent improvement in the terms of trade, while an appreciation of about 2 to 3½ per cent is associated with an increase of 1 percentage point in the differential between Australian and world long real interest rates.

There has been a recent resurgence of interest in the concept of progress and how it is measured. This paper explores the role that concepts of wellbeing and sustainability play in informing a framework for public policy analysis with a particular focus on the Australian Treasury. Treasury's policy objective, set out in its mission statement, is to improve the wellbeing of the Australian people. As such, sustainable social progress or improving wellbeing, and how it is measured, are of central concern to the work of the Treasury.

We present a simple model of the macroeconomy that includes a role for an asset-price bubble, and derive optimal monetary policy settings for two policy-makers. The first policy-maker, a sceptic, does not attempt to forecast the future possible paths for the asset-price bubble when setting policy. The second policy-maker, an activist, takes into account the complete stochastic implications of the bubble when setting policy. We examine the optimal policy recommendations of these two policy-makers across a range of plausible assumptions about the bubble. We show that the optimal monetary policy recommendations of the activist depend on the detailed stochastic properties of the bubble. There are some circumstances in which the activist clearly recommends tighter policy than that of the sceptic, while in other cases, the appropriate recommendation is to be looser than the sceptic. Other things equal, the case for ‘leaning against’ a bubble with monetary policy is stronger the lower the probability of the bubble bursting of its own accord, the larger the efficiency losses associated with big bubbles, and the higher the assumed impact of monetary policy on the bubble process.

This article examines Treasury's macroeconomic forecasting performance over the period from 1989-90 to 2003-04, with a focus on forecasts of nominal and real GDP, the GDP deflator, the unemployment rate, and CPI inflation.

This paper examines the fiscal implications of a significant rise in Australian labour force participation or labour productivity growth over the next forty years, relative to the projections in the Australian Government’s 2002-03 Intergenerational Report (IGR). The alternative, higher, labour force participation projections assume that Australian participation rates by age and gender rise gradually over the next twenty years to just reach the top one fifth of the current experience of the OECD, and then remain at these higher levels over the subsequent twenty years. Results for higher productivity growth are presented for two alternative assumptions. Both assume average economy wide labour productivity growth at an annual rate of 2 ¼ per cent, which is ½ per cent faster than assumed in the IGR but close to its average rate since the early 1990s. They differ, however, in the assumed coverage across the economy of the higher productivity growth. The first alternative assumes higher productivity growth that is shared across all sectors of the economy, while the second assumes no rise, relative to the IGR, in productivity growth in government funded service sectors. The paper describes how the significant areas of Australian Government expenditure are modelled for the alternative projections, with a focus on Australian Government health expenditure, and in particular on the non-demographic component of that expenditure, because of its importance for the fiscal projections. The paper also presents estimates of the 'fiscal gap' for the IGR and the three alternative projections. The long term fiscal projections for all three alternative assumptions are more favourable than those in the IGR. The projection that assumes higher productivity that is not shared by government funded service sectors generates only a small fiscal improvement; the projection that assumes higher productivity that is shared across all sectors generates a significantly larger improvement, while the largest fiscal improvement occurs for the higher participation projection. The paper explores the reasons for this ordering, which arises primarily because of the economic relationship between labour productivity and real wages, and the link from real wages to the cost of providing both government services and government payments to individuals. The fiscal improvements for both the projection that assumes higher productivity that is shared across all sectors, and the higher participation projection are sufficiently large that, were either to be realised, that component of the IGR fiscal gap arising from the ageing of the population would be more than eliminated, although the rest of the IGR fiscal gap — arising from non-demographic growth in Australian Government health spending — would not be.

It is often argued that the United States cannot continue for long to run current account deficits of their current size of 5 per cent of Gross Domestic Product (GDP). This article questions this conventional wisdom by examining the implications were the United States to continue to run current account deficits of 5 per cent of GDP for the next ten years.

This paper examines the output implications of a significant rise in Australian labour force participation over the next forty years. Using the projections in the Commonwealth Government’s 2002-03 Intergenerational Report as a benchmark, it generates alternative projections assuming that, for each age-and-gender cohort, Australian participation rates rise gradually over (roughly) the next twenty years to reach the 80th percentile of the distribution of current participation rates across the OECD. Over the following twenty years, it assumes that Australian participation rates remain at these higher values. These alternative projections, if they were realised, would imply gradually rising aggregate labour force participation in Australia for most of the next twenty years, rather than gradually falling participation, as projected in the Intergenerational Report. Output in twenty years time would be about 9 per cent higher than that projected in the Intergenerational Report, and would remain about 9 per cent higher for the following twenty years. About one-third of the rise in output in these alternative projections would be accounted for by higher participation by 45-64 year old males, and between one-sixth and one-quarter by higher participation by people aged 65 and over. Some of the rise in participation rates in the alternative projections could occur as a consequence of recent rises in educational attainment flowing through to older age groups over time. Much of the rise, were it to occur, would need to come about as a consequence of changes in policy and in community attitudes, particularly to older workers.

The output gap – the difference between actual and potential output – is widely regarded as a useful guide to future inflationary pressures, as well as an important indicator of the state of the economy in its own right. Since the output gap is unobservable, however, its estimation is prone to error, particularly in real time. Errors result both from revisions to the underlying data, as well as from end-point problems that are endemic to econometric procedures used to estimate output gaps. These problems reduce the reliability of output gaps estimated in real time, and lead to questions about their usefulness. We examine 121 vintages of Australian GDP data to assess the seriousness of these problems. Our study, which is the first to address these issues using Australian data, is of interest for the method we use to obtain real-time output-gap estimates. Over the past 28 years, our real-time output-gap estimates show no apparent bias, when compared with final output-gap estimates derived with the benefit of hindsight using the latest available data. Furthermore, the root-mean-square difference between the real-time and final output-gap series is less than 2 percentage points, and the correlation between them is over 0.8. Our general conclusion is that quite good estimates of the output gap can be generated in real time, provided a sufficiently flexible and robust approach is used to obtain them.

This paper presents a small model of the Australian macroeconomy. The model is empirically based, aggregate in nature and consists of five estimated equations – for non-farm output, the real exchange rate, import prices, unit labour costs and consumer prices. The stylised facts underlying each equation are discussed and estimation results are presented. The model’s primary use is to examine macroeconomic developments over the short to medium term, although it also has a well-defined steady state in the longer run with appropriate theoretical properties. Dynamic responses of the model to monetary policy changes and selected shocks are illustrated in the paper.

The efficient market hypothesis states that asset prices in financial markets should reflect all available information; as a consequence, prices should always be consistent with ‘fundamentals’. In this paper, we discuss the main ideas behind the efficient market hypothesis, and provide a guide as to which of its predictions seem to be borne out by empirical evidence, and which do not. In examining the empirical evidence, we concentrate on the stock and foreign exchange markets. The efficient market hypothesis is almost certainly the right place to start when thinking about asset price formation. The evidence suggests, however, that it cannot explain some important and worrying features of asset market behaviour. Most importantly for the wider goal of efficient resource allocation, financial market prices appear at times to be subject to substantial misalignments, which can persist for extended periods of time.

In this paper we discuss the development of Phillips curves in Australia over the forty years since Phillips first estimated one using Australian data. We examine the central issues faced by researchers estimating Australian Phillips curves. These include the distinction between the short and long-run trade-offs between inflation and unemployment, and the changing level of the non-accelerating inflation rate of unemployment (NAIRU), particularly in the 1970s. We estimate Phillips curves for prices and unit labour costs in Australia over the past three decades. These Phillips curves allow the NAIRU to change through time, and include a role for import prices and ‘speed-limit’ effects. The paper concludes by presenting an extended discussion of the changing role of the Phillips curve in the intellectual framework used to analyse inflation within the Reserve Bank of Australia over the past three decades.

The paper is motivated by two empirical results. Australia’s terms of trade exhibit temporary fluctuations around a slowly declining trend, and movements in Australia’s real exchange rate tend to follow those in the terms of trade. Together these results imply predictability in Australia’s real exchange rate as well as the presence of predictable excess returns that are sometimes quite large. Using a simple econometric model, with the terms of trade as the sole explanator, the paper demonstrates the forecastability of Australia’s real exchange rate over horizons ranging from one to two years. It then quantifies the magnitude of the predictable excess returns to holding Australian dollar denominated assets over such horizons, finding them to be highly variable and sometimes quite large in magnitude. The results suggest a relative scarcity of forward-looking foreign exchange market participants with an investment horizon of a year or more.

Inflation in the 1990s in most industrial countries is lower and less variable than at any time in the past quarter of a century. Economic theory predicts that, other things equal, this decline in inflation variability should lead to less volatility in both bond and foreign exchange markets. The paper tests these theoretical predictions and finds some evidence that lower inflation variability leads to less volatility of bond yields, but almost no evidence that it leads to lower volatility of floating exchange rates.

While economic theory is largely mute on the question of whether macroeconomic policies affect long-run growth, an examination of the experience of different countries over various periods and the policies they pursued, lends strong support to the idea that macro policies do play a role in the growth process. A macroeconomic policy framework conducive to growth can be characterised by five features: a low and predictable inflation rate; an appropriate real interest rate; a stable and sustainable fiscal policy; a competitive and predictable real exchange rate; and a balance of payments that is regarded as viable. Countries with these macroeconomic characteristics tend to grow faster than those without them, though there are many individual cases of both developing and developed countries suggesting that satisfying only some of these conditions does not sustain strong growth. It is also important to recognise that the direction of causation is somewhat ambiguous: while good macro outcomes should be conducive to growth, strong growth is also conducive to good macroeconomic outcomes. The paper presents a wide-ranging examination of both theoretical and empirical evidence on the many ways macroeconomic policies may influence economic growth. Given monetary policy’s crucial role in determining the inflation rate in the longer run, there is a particular emphasis on the relationship between inflation and growth. The following five broad conclusions are drawn. First, although growth models assign a major role to capital accumulation, there is little evidence that aggregate investment yields excess returns, and so special policy incentives to boost aggregate investment appear inappropriate. Second, countries with low national saving invest less and grow more slowly than they would if saving were higher. Ultimately, the extent to which a country can rely on foreign savings to fund domestic investment and growth depends on the rate of capital inflow the market accepts as sustainable. For Australia, with abundant natural resources and a stable political environment, this may be higher than for many other capital importing countries. Third, declining national saving rates in many industrial countries are primarily a consequence of lower government saving, suggesting a need for reduced fiscal deficits. In Australia, however, private savings have also fallen substantially, suggesting a possible role for specific incentives to boost private savings. Fourth, when economies are near potential, short-run rises in output seem to be more inflationary than falls in output are disinflationary. This implies that macroeconomic policy acting pre-emptively to counter expected future demand pressures and quickly mitigating the effects of unexpected shocks has a positive effect on the level of output, compared with a more hesitant approach acting only when demand pressures have appeared. Further, provided inflation is kept close to its target in the medium term, policy which tolerates some short-term deviations of inflation from its target reduces fluctuations in real output and generates a higher long-run output level than a policy with the sole goal of keeping inflation close to its target. Finally, although most economists believe even moderate rates of inflation adversely affect growth, unambiguous evidence has been difficult to come by. There is still professional disagreement on the robustness of the empirical evidence, but it does appear that higher inflation, and the associated increased uncertainty about future inflation, adversely affects growth in the industrial countries. The gains from lower inflation appear to exceed the initial costs of reducing inflation within about a decade.

A recent model of firms’ pricing behaviour by Laurence Ball and Gregory Mankiw has novel implications for the effect of relative price shocks on inflation. This paper examines these implications and establishes the importance of expected inflation for this story. We derive the model relationship between expected inflation, the economy-wide distribution of industry price changes and actual inflation, and show that both Australian and US industry-price data strongly support this derived relationship. The inflationary impact of relative price shocks depends strongly on expected inflation. When expected inflation is high, a rise in the economy-wide dispersion of shocks is inflationary in the short-run. By contrast, when expected inflation is low, a rise in the dispersion of shocks has minimal impact on inflation. Economy-wide relative price shocks, like terms of trade shocks, are an unavoidable feature of the economic landscape. Their disruptive effect on inflation is minimal, however, when average inflation, and therefore average expected inflation, is kept low.