The multiple filter test for change point detection in time series

A framework for the detection of change points in the expectation in sequences of random variables is presented. Specifically, we investigate time series with general distributional assumptions that may show an unknown number of change points in the expectation occurring on multiple time scales and that may also contain change points in other parameters. To that end we propose a multiple filter test (MFT) that tests the null hypothesis of constant expectation and, in case of rejection of the null hypothesis, an algorithm that estimates the change points.The MFT has three important benefits. First, it allows for general distributional assumptions in the underlying model, assuming piecewise sequences of i.i.d. random variables, where also relaxations with regard to identical distribution or independence are possible. Second, it uses a MOSUM type statistic and an asymptotic setting in which the MOSUM process converges weakly to a functional of a Brownian motion which is then used to simulate the rejection threshold of the statistical test. This approach enables a simultaneous application of multiple MOSUM processes which improves the detection of change points that occur on different time scales. Third, we also show that the method is practically robust against changes in other distributional parameters such as the variance or higher order moments which might occur with or even without a change in expectation. A function implementing the described test and change point estimation is available in the R package MFT.     

Effective HR implementation: the impact of supervisor support for policy use on employee perceptions and attitudes

Abstract

Effective implementation of human resource (HR) policies appears to depend on supervisors’ active involvement in the intervention process. Following recommendations of a recent intervention evaluation framework, we examine how perceived supervisor support during the implementation of a work-life intervention helps to change participants’ perceptions of organizational family supportiveness, and how this ultimately changes participants’ engagement and turnover intentions. A three-wave longitudinal study in a professional services firm (N = 434) that has formally involved supervisors in the process of a work-life intervention showed support for our study hypotheses. Supervisor support for policy use influenced employees’ positive work–home culture perceptions, which in turn strengthened employees’ work engagement and diminished their turnover intentions over time. We discuss practical implications and give recommendations on the future design of HR interventions and related policies.     

Green marketing strategies: an examination of stakeholders and the opportunities they present

As green marketing strategies become increasingly more important to firms adhering to a triple-bottom line performance evaluation, the present research seeks to better understand the role of “green” as a marketing strategy. Through an integration of the marketing, management, and operations literatures, an investigative framework is generated that identifies the various stakeholders potentially impacted through the environmentally friendly efforts of a firm. Specifically, the inter-connected nature of the core business disciplines of marketing, management (both strategy and human resources), and operations are examined as controllable functions within an organization from which strategies can be enacted to affect a firm’s stakeholders. The prior research in these areas is examined to identify potential research opportunities in marketing while also offering a series of representative research questions that can help guide future research in marketing.     

The gift of advice: communication in a bilateral gift exchange game

We augment a standard bilateral gift exchange game so employees can send messages at the same time as choosing an effort level. Employee effort (controlling for wages) is unaffected by allowing messages, but wages dramatically increase. Messages affect wages because employees give managers advice to set higher wages, usually explaining that this will result in higher effort. This advice prompts managers to try higher wages, helping them learn that raising wages increases their payoffs. In a follow-up experiment, we directly provide managers with additional information about the relationship between wages and effort. This too causes wages to increase, but to a lesser extent than allowing messages. Our results highlight the critical role of learning in generating gains from positive gift exchange.     

Monetising the Classical Equations: a theory of circulation

The Classical Equations describe output and income in real terms.To use them to analyse aggregate demand, the transactions theydescribe must be ‘monetised’. A sum of money equalto the wage bill of the capital goods sector can be shown tobe necessary and sufficient to carry out all transactions, ina process of circulation which also defines an expression forvelocity. When money has intrinsic value, the quantity approachmay hold in the short run but, in the long run, money will beendogenous. In these conditions, the rate of interest will bedetermined by the supply and demand for reserves, but when moneyis purely nominal, only a minimum rate will be fixed, and therate of interest will have to be pegged. The Appendix developsthe Classical Equations and shows that they define an invariableunit of account.     

On the Composition of Committees

This article is concerned with the role of committees in collectivedecision making processes in a world where agents must be motivatedto collect information. Committees improve the quality of decisionmaking by providing information and by coordinating the collectionof information. We address two types of questions. First, howdoes the composition of a committee affect final decisions?Second, what is the optimal composition of a committee fromthe decision maker's point of view? As to the latter question,we show that the cost of information collection plays an importantrole. If this cost is low, then the preferences of the committeemembers should be aligned to those of the decision maker. Memberswith similar preferences as the decision maker collect the properpieces of information. Moreover, manipulation of informationdoes not occur if the preferences of the decision maker andthe members are consonant. If the cost of searching is high,then the committee should be composed of members with polarizedpreferences. Outliers have a strong incentive to search forinformation.