In recent years，A "repeated crisis" has aroused great attention in the scientific community。The "birth" of the crisis originated from two types of arguments。First, statistical investigation discovery，Some published scientific research results are difficult to be reused。In Life Science、Physiology、Popular disease、Ecological and other areas，The proportion that cannot be repeated in a specific research direction can even reach more than 75%。Second, some scientific workers admit that they will not conduct repeated experiments in daily scientific research。The former explains today where the number of thesis is increased in the form of index.，The scale that cannot be repeated cannot be underestimated。The latter trigger a greater degree of concerns: If scientists do not do repeat experiments，Then the above -mentioned proportion of considerable unavailable results will not be tested and questioned，So that scientific progress is based on unreliable research data。But，It is worth noting that，Although scientists are limited by time、Resources and issuance of incentive system，Indeed, it is really rare to conduct a complete repetitive experiment on the research of others，But it does not mean that there is no duplicate experimental design in scientific activities。Under the new perspective of new experimental and methodological diversity of scientific philosophy，We can go deep into the details of scientific practice，Understanding how scientists deal with this problem。

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The new experimentalism from the ZTE of Scientific Philosophy in the 1980s，The research perspective of traditional theoretical advantages to the perspective of the theoretical advantage to the experimental activity with vitality。Experiments are no longer simply regarded as an experience tool for verifying theory，Instead Bet365 lotto review of rich forms and cognitive significance。Based on this position，We can distinguish the repeated experiments into two categories according to the purpose: the existence experiment of the existence of the inspection experience、Repeated experiments of Robustness (Robustness)。

The presence test requires confirmation that the phenomenon is stable rather than accidental，and confirm whether the experimental process and parameter settings are accurate or redundant。On the one hand，Researchers should conduct sexual tests on their own research。Once a preliminary phenomenon is obtained，Several repeated experiments should be performed to determine that the phenomenon can occur stable。After the accidentality is excluded，Still need to check whether the experimental design contains the factors that have not been noticed that the phenomenon can cause phenomenon，This will cause a great systemic deviation。For example，In an experiment with fluorescent protein detection of cell activity，Afterwards, it is found that the complex used to regulate cell activity can produce fluorescence。Therefore，Process inspection requires small -scale changes in common experimental conditions，so as not to fall into the "standardization fallacy" -the stringent experimental condition control，The more you get the phenomenon that can be repeated。

Stable expansion meaning is to find experience evidence that is sufficient to provide multiple decisiveness (Multiple Determination)。Under this purpose，Researchers should introduce a large degree of changes in the experimental design，The scope of the establishment of phenomena and conclusions。For example，In the study of life science，The common approach is to change different properties、Experimental animals of species，Use different types of characterization instruments (such as microscope and spectrometer with different principles), etc.。Diversity due to the characteristics of biology and its molecular characteristics，Use different experimental objects and instruments to test one Bet365 app download by one is usually an inevitable requirement for expanding the stability of the conclusion。

　　Explore different repeated experimental methods

The following introduces the specific experimental design that can realize the two different goals that can achieve existence testing and stability test。Where，About the presence test，The two types of duplicate experiments are mainly introduced to the two types of two types of micro -repeat experiments and large -scale repeated experiments;，Mainly introduce the two types of duplicate experimental design of concept repeat experiments and data repeated experiments。

Micro -heavy repeat experiments。Usually need to set strict experimental control during the experiment，When setting related parameters and selection of experimental materials, you need to refer to the background knowledge provided by the predecessors。But，Researchers when using these background knowledge，It will not be directly applied directly，Instead, a local "micro replication" (micro replication) was performed by the blank control experiments implemented before the core experiment，to obtain the bottom value of the data used to eliminate interference。For example，In Vitro Binding Assay experiments，Considering the nature of the protein For the experimental environment (ion concentration、pH value, etc.) Very sensitive，False positive control testing of the solution system before combining measurement，and pseudoma -negative control test of the signal peptide label。These two types of tests constitute a repeated experimental test for all background knowledge。In the above -mentioned fluorescent protein research，The solution system that adds active regulatory substances but has not added cells，Perform micro -duplex inspection experiments。Using this design can avoid false positive results in the core experimental part。Micro -repeated experiment itself as part of the control conditions of the setting and testing experiment，Generally existing in general experimental research。Different understanding bet365 Play online games of duplicate experiments，Micro -repeatting is not a complete repetition of predecessors' research，But it has established a repetitive relationship between the new research and the original research，It constitutes an effective local existence test。This duplicate relationship can be reflected in the citation network。but but，From the writing method of scientific research literature，Researchers use micro -repeat，But it will avoid reports that encounter duplicate failures in practice，It will only establish a contact with the repetitive predecessor research。Therefore，Micro -repeated experiments do not have the functions of screening and labels that cannot be repeated in literature，Can't further explain the cause of the failure。

Large -scale repeated experiments。Large -scale repeated experiments can conduct sexual inspection of reliable research results in specific fields，At the same time, it will also pay attention to and report failure，Therefore, insufficient function of filling micro -repeat experiments to a certain extent。Current，Many international organizations are testing the repetitiveness of the literature in the field of disciplines。For example，Professor of Psychology at the University of Virginia、The Open Science Collaboration, an open scientific cooperation organization established by the top ten years of the "Nature" magazine in 2015, and others established.，In 2012。Results indicate，61%research failed to repeat it successfully。Since the project requires repeated experimental research teams to communicate with the original author before and after completion，Therefore, it helps to prevent repeated failures caused by imperfect experimental operations，It can also be further checked through cooperation to check the specific reasons for repeated failures，Overall is beneficial to improving the reliability of research in related fields。other，Large -scale repeated experiments can help reduce the cost of duplicate experiments through academic community cooperation，To avoid researchers from obstructing the obstacles of the incentive system without participating bet365 Play online games in repeated experiments。In the long run，This helps to reduce the proportion of non -repeated literature，and be able to discover academic fraud in time。

Concept repeat experiments。Conceptual Replication is common in psychology、The field of ecology，Refers to the premise of deliberately changing the core variable in the experiment，Try to reproduce the variable relationship in previous studies，That is the same theoretical hypothesis of research，"Small" hypothesis is similar but inconsistent。For example，In the experimental experiment of cognitive psychology，The overall purpose of similar research is to explore whether physical perception can affect cognition，Therefore, the degree of roughness of the object or hardness can constitute a set of concepts to repeat the different variables in the experiment。Concept repeat experiments through changing the value type of variable，Make the experimental conclusion in a more common situation，Improving the stability of the research results。but but，There are also some scholars who question the concept of repeated experimental pseudo。They are worried that only the concept of success will be used to support the original conclusion，The concept of failure cannot be regarded as a strict recovery of the original experiments，Therefore, it is impossible to constitute a valid evidence。Despite this，The concept of success is still aware of the significance。

Data repeat experiments。In some special large -scale experiments research，The original experimental data cannot be repeatedly measured，At this time, you can use data to repeat to verify the stability of the research conclusion。For example，In the study of climate change，We want to know if the temperature on the surface of the earth has really risen in the past 60 years。But only a few research institutions that have conducted long -term effective observations (such as the University of East Angelia Climate Research Center、The British Meteorological Administration Had Lai Cai) The original data provided by the British Meteorological Administration can be available，and the Bet365 lotto review data cannot be obtained again。For repeated inspection，National Aerospace Bureau/New York Goddard Space Institute、Different research teams such as the National Ocean and Atmospheric Administration of the National Oceanic and atmospheric Administration independently processed different methods of the original data (such as different fitting methods、Definitely calculate the average value of different areas, etc.)，Finally verified the stability of the conclusion。Data repeated can make full use of such precious experimental resources，Questions in the measurement of correction data，Make sure the experimental results pass the stability test。but，This kind of research cannot conduct strict experiments in a strict sense，Therefore, it is necessary to consider whether the conclusion can be consistent with the experience evidence of other sources.。

Four repeated experiment methods discussed above can achieve different purposes of existence or stability test，At the same time, there are their own applicable scenarios and defects。S. Mitchell、N. Cartwright and other scientific philosophers advocated by scientific philosophers from the perspective of diversified perspectives，Gold standards that should not be pursued in the experimental design，Instead, according to the purpose of specific research、Object、Background knowledge and other factors to evaluate、Experimental methods with higher applicability of improvement and invention。Therefore，The coexistence of a variety of repeated experiments is necessary。

It is worth noting that，The repeated experiments described in this article are from actual scientific research cases，But these are not a complete reproduction of a certain research in the traditional sense，but duplicate that can be embedded in general experimental design。This also answered the question "Why do scientists don't do duplicate experiments in traditional sense"。When understanding repetitive，We can not regard repeated experiments as an export of conventional scientific research activities，Instead, Bet365 app download examine how to integrate it into the experimental design idea。In -depth understanding of experimental design strategies in cutting -edge scientific research，It can relieve concerns about the existence of repeated crisis in the overall crisis of science。

　(Author Unit: Department of Science University of Tsinghua University)