Competing for attention in social communication markets

We investigate the incentives for social communication in the new social media technologies. Three features of online social communication are represented in the model. First, new social media platforms allow for increased connectivity; i.e., they enable sending messages to many more receivers, for the same fixed cost, compared to traditional word of mouth. Second, users contribute content because they derive status- or image-based utility from being listened to by their peers. Third, we capture the role of social differentiation, or how social distance between people affects their preferences for messages. In the model, agents endogenously decide whether to be a sender of information and then compete for the attention of receivers. An important point of this paper is that social communication incentives diminish even as the reach or the span of communication increases. As the span of communication increases, competition between senders for receiver attention becomes more intense, resulting in senders competing with greater equilibrium messaging effort. This in turn leads to lower equilibrium payoffs and the entry of fewer senders. This result provides a strategic rationale for the socalled participation inequality phenomenon, which is a characteristic of many social media platforms. We also show that social differentiation may enhance or deter sender entry depending on whether it can be endogenously influenced by senders. Finally, we examine how the underlying network structure (in terms of its density and its degree distribution) affects communication and uncover a nonmonotonic pattern in that increased connectivity first increases and then reduces the entry of senders

The peacebuilding potential of healthcare training programs.

Global health professionals regularly conduct healthcare trainings, such as first aid courses, in disadvantaged communities across the world. Many of these communities lack healthcare infrastructure because of war and political conflict. The authors draw on their experience conducting a first aid course in South Sudan to provide a perspective on how healthcare trainings for people with no medical background can be used to bridge ethnic, political, and religious differences. They argue that a necessary step for turning a healthcare training into a vehicle for peacebuilding is to bring people from different communities to the same physical space to learn the course material together. Importantly, simply encouraging contact between communities is unlikely to improve intergroup relations and could be detrimental if the following features are not incorporated. Buy-in from respected community leaders is essential to ensure that training participants trust that their safety during the training sessions is not at risk. Trainers should also create a supportive environment by conferring equal status and respect on all trainees. Finally, hands-on training exercises allow for positive interactions between trainees from different groups, which in turn can challenge stereotypes and facilitate cross-group friendships. These features map onto social psychological principles that have been shown to improve intergroup relations and are consistent with lessons learned from peace through health initiatives in public health and medicine. By adopting peacebuilding features, healthcare trainings can serve their primary goal of medical education and provide the added benefit of strengthening social relations

Farm Inputs and Agri-Environment Measures as Indicators of Agri-Environment Quality in Hungary

The paper deals with agri-environmental indicators, examines farm inputs, on the basis of statistical data of the Organisation for Economic Co-operation and Development (OECD) (Szabo, Pomazi 2002) and the Eurostat (2004). The examined indicators are placed in the agricultural DPSIR model. The paper presents how the use of farm inputs changed in Hungary from 1980-2000. Farm inputs are related to the inputs of the EU-15, the study demonstrates that today they are below the EU- 15 average. Area under agri-environmental measures in 2003 - which covered the 4% of agricultural area of Hungary - as a response indicator is also presented and based in the land-use zone system developed by Godollo Agricultural University (Angyan et al., 1998).agri-environmental measures, farm inputs, indicators, Environmental Economics and Policy, Q01,

A lepkész Schmidt Antal (1880–1966): a muzeológus és az igazgató öröksége a Magyar Természettudományi Múzeumban = The lepidopterist Dr. Antal Schmidt (1880–1966): his legacy as curator and director in the Hungarian Natural History Museum

Dr Antal Schmidt, lepidopterist by scientifi c interest, worked as staff member of the Hungarian Natural History Museum between the period 1903–1939. Personal data of Schmidt are given, with a list of all his 22 publications and 25 Lepidoptera names proposed as new for science. On the basis of archive records and documents the alphabetic list of 598 personalities he corresponded with is also compiled indicating the intensity of letter exchange. People whom Schmidt was in most intensive contact with, are briefl y presented. With 12 fi gures

A coding problem for pairs of subsets

Let $X$ be an $n$--element finite set, $0<k\leq n/2$ an integer. Suppose that $\{A_1,A_2\}$ and $\{B_1,B_2\}$ are pairs of disjoint $k$-element subsets of $X$ (that is, $|A_1|=|A_2|=|B_1|=|B_2|=k$, $A_1\cap A_2=\emptyset$, $B_1\cap B_2=\emptyset$). Define the distance of these pairs by $d(\{A_1,A_2\} ,\{B_1,B_2\})=\min \{|A_1-B_1|+|A_2-B_2|, |A_1-B_2|+|A_2-B_1|\}$. This is the minimum number of elements of $A_1\cup A_2$ one has to move to obtain the other pair $\{B_1,B_2\}$. Let $C(n,k,d)$ be the maximum size of a family of pairs of disjoint subsets, such that the distance of any two pairs is at least $d$. Here we establish a conjecture of Brightwell and Katona concerning an asymptotic formula for $C(n,k,d)$ for $k,d$ are fixed and $n\to \infty$. Also, we find the exact value of $C(n,k,d)$ in an infinite number of cases, by using special difference sets of integers. Finally, the questions discussed above are put into a more general context and a number of coding theory type problems are proposed.Comment: 11 pages (minor changes, and new citations added

The AdHOC study of older adults’ adherence to medication in 11 countries

BACKGROUND: Compared with the resources expended developing, evaluating and making clinical decisions about prescribing medication, we know little about what determines whether people take it. Older adults are prescribed more medication than any other group. Poor adherence is a common reason for nonresponse to medication. OBJECTIVES: To investigate cross-nationally the impact of demographic, psychiatric (including cognitive), physical health, behavioural and medication factors on adherence to medication in older adults. METHODS: Researchers interviewed 3881 people over 65 who receive home care services using a structured interview at participants’ places of residence in eleven countries. The main outcome measure was the percentage participants not adherent to medication. RESULTS: 12.5% (n= 456) of people reported they were not fully adherent to medication. Non-adherence was predicted by problem drinking (OR=3.6), not having a doctor review medication (OR=3.3), dementia (OR=1.4 for every one point increase in impairment), good physical health (OR=1.2), resisting care (OR=2.1) being married (OR=2.3) and living in the Czech Republic (OR=4.7) or Germany (OR=1.4). CONCLUSION: People, who screen positive for problem drinking and with dementia, often undiagnosed are less likely to adhere to medication. Therefore doctors should consider dementia and problem drinking when prescribing for older adults. Interventions to improve adherence in older adults might be more effective if 4 targeted at these groups. It is possible that medication review enhances adherence, by improving the patient-doctor relationship, or by emphasising the relevance of medications

Monetary costs of agitation in older adults with Alzheimer's disease in the UK: prospective cohort study

While nearly half of all people with Alzheimer's disease (AD) have agitation symptoms every month, little is known about the costs of agitation in AD. We calculated the monetary costs associated with agitation in older adults with AD in the UK from a National Health Service and personal social services perspective