Based on the simulation study of the publication delay control process [Yu & al., 2005], transfer function models of delay control processes by adjusting the accepted contribution flux and the published
contribution flux are identified using system identification. According to Cybernetics, the feedback control system of the
publication delay is designed and control processes are simulated and analyzed when the average publication delay are regarded
as the controlled object. On the basis of the relation between the average publication delay and the deposited contribution
quantity, another control method is proposed that the deposited contribution quantity is regarded as the controlled object
and the simulation result proves that the method is an excellent means and can help editors expediently manage their journals
and control publication delays.
Owing to some discussions about manipulating impact factor by requesting authors to increase their citations to the publication
journal, we theoretically establish a mathematical expression of a relation between the journal self-citation rate and its
impact factor by the single-factor method in this paper. Based on self-citation data of some journals in JCR and the observed
relation between journal impact factor and the self-cited rate, we analyze the possibility that journal editors manipulate
impact factors of their journals by raising the self-cited rate. Finally, we make some suggestions for supervising this crude
way of active manipulating the impact factor.
In this article, we firstly analyze the referencing process and the citation process of a scientific journal in theory, and
find that the observed referencing or citation process includes the diffusing process and the aging process of cited literature
and the publishing process of citing literature, thereby it is illuminated why the identified average publication delay
was longer than the observed value. Secondly, we compare the transfer function model of the observed citing process with
other classical citation distribution models and find that the model is superior to others. Finally, using the model, we identify
parameters of actual referencing and citation processes from data of age distributions of references and citations of 38 journals
of neurology and applied mathematics in JCR, respectively; and then compare differences of identified parameters and obtain
some interesting conclusions.
Based on the transfer function model of the observed citation distribution and the expression of the cumulative citation probability
distribution, parameters of 12 citation distributions are identified from statistical data of age distributions of references
of 10 journals in JCR using the parameter optimization fitting method. At same time, based on the steady state solution of
differential equations of the publication delay process and data of publication delays of 10 journals, the publication delay
parameters of every journal are identified using the fitting method. Identified parameters of every journal citation distribution
are compared with the journal’s publication delay parameters and some valuable conclusions are deduced.
The steady state solution of differential equations of periodical publication process is deduced, and based on this, the indicator of periodical publication delay, which reflects the degree of information ageing in editorial board of a periodical, is established. The indicator is proved to be the sum of two items: the pure publication delay, which reflects the editing rapidity of a periodical, and the ratio of deposited contribution quantity to the publishing quantity in one year, which reflects the waiting period of adopted papers deposited in editorial board. As a demonstration, the delay indicators of seven periodicals are calculated. Finally, the application of this indicator is discussed.
Summary According to the discrete model of periodical publication process, recurrence formulae of parameters of the process are gained and the initial conditions of control process parameters from one steady state to another are deduced. Using the variable separation approach, which is used generally to solve the partial differential equation, the recurrence computing formula of the publication probability function is deduced. First the publication delay increasing process caused by the accepted contribution flux increase is simulated, and then the publication delay decreasing processes under four different control means are simulated too. Finally it is demonstrated that the periodical publishing process is a strong inertia system and it is found that reducing the quantity of deposited contributions can shorten the publication delay.
In this paper, we discuss the application of the data mining tools to identify typical features for highly cited papers (HCPs). By integrating papers’ external features and quality features, the feature space used to model HCPs was established. Then, a series of predictor teams were extracted from the feature space with rough set reduction framework. Each predictor team was used to construct a base classifier. Then the five base classifiers with the highest classification performance and larger diversity on whole were selected to construct a multi-classifier system (MCS) for HCPs. The combination prediction model obtained better performance than models of a single predictor team. 11 typical prediction features for HCPs were extracted on the basis of the MCS. The findings show that both the papers’ inner quality and external features, mainly represented as the reputation of the authors and journals, contribute to generation of HCPs in future.
The inter-citation journal group is defined as a group of journals with inter-citation relations. In this paper, according
to the 2003 JCR, an inter-citation relation matrix of 10 medical journals is established. Based on the transfer function model
of the disturbed citing process, the calculation formula of journal impact factor disturbed by publication delays of certain
journal in the group is deduced and a changing process of every journal's impact factor caused by the increase of each journal's
average publication delay is simulated. In the inter-citation journal group, when a journal's publication delay increase,
impact factors of all journals will be decreased and rankings of journals according to the impact factor may be changed. The
closer a citation relation between two journals, the stronger the interaction of them and the larger the decrease of their
impact factors caused by the increase of their publication delays.
Based on the transform
function model of the observed citing process, the analytical expression of the
age distribution of citations is deduced, and it is theoretically proved that
the peak value of the citation distribution curve would fall and shift backward
along with increasing the average publication delay and the peak age has a
direct proportion relation with the pure delay and would be prolonged along
with increasing the delay or decreasing the aging rate. The influence of the
average publication delay on three ISI indicators impact factor, immediacy
index and cited half-life are studied; in one subject discipline, the bigger
the delay, the lower the three indicators of journals. Using the sensitivity
theory, sensitivity formulae of the three indicators to publication delay
parameters are deduced and it is found that responses of these indicators to
changes of publication delays are different according to different time
constant of the aging process; The faster the aging rate of a discipline
literature is, the worse the influence of publication delays on the indicators
of journals in the discipline.
In this paper, the internal law of delay in the secondary literature publishing process is presented. The process is demonstrated
to abide by the partial differential equation of periodical literature publishing process. A definite solution of the publishing
delay process is derived. Accordingly, the expression of average publication delay indicator based on the particular solution
is deduced. Then the problem is studied that some information of primary literatures is missed in information retrieval, and
the relationship is established between the average delay indicator and the miss ratio of primary literatures in the index
periodicals or databases. Also it is proposed that the primary literature should be used as a supplemental tool in information
retrieval to guarantee the recall ratio.