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Journal Citations and Impact Factor

Last week, I talked about H-Index which is a metric for measuring the impact an author has in his field.  This week, I will discuss Impact Factor (IF) which is one way to measure the impact a journal has in a field. Impact Factors for a journal are available through Journal Citation Reports which is produced by the same company that produces Web of Knowledge.  The simple impact factor for a journal in any given year is the average number of citations in that year of articles from the previous two years.  So if a journal has an impact...
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H-Index

As I mentioned last week, I decided that there wasn’t enough interesting about controlled vocabulary to fill up a whole month of posts so I’ve decided to switch topics for this week and next to journal metrics.  The first metric I’m using in some research I’m conducting with a professor, and it’s called the H-Index. H-Index was originally introduced by J.E. Hirsch as one way of measuring an author’s impact on his field.  The way it works is you order the author’s papers from the most to least cited paper along the x-axis.  Then you graph on the y-axis...
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More Controlled Vocabulary

As I mentioned last week, my original theme for the month was to go over controlled vocabulary such as the Physics and Astronomy Classification Scheme (PACS) used in Scitation and IEEE Xplore, the Mathematics Subject Classification (MCS) used in MathSciNet, and the Computing Classification System (CCS) used in the ACM Digital Library.  But I decided that there wasn’t enough to say to blog about each one separately. All of them have similar hierarchical structure like MeSH, but without as many tiers.  PACS has up to 5 subheadings, MCS up to 3, and CCS up to 3.  The headings and...
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MeSH Descriptors

Last week talked about chemistry.  Today we talk about medicine.  Specifically, we will discuss Medical Subject Headings (MeSH).  MeSH is an example of controlled vocabulary which we is our topic for this month.  Controlled vocabulary is used in indexes to describe subjects systematically and consistently, and MeSH descriptors are probably some of the most widely used.  It’s no surprise that MedLine, PubGet, PubMed use MeSH since they’re biology related.  But they’re used in Scopus and IEEE Xplore also. MeSH were created by the National Library of Medicine and are updated every year.  Currently there are over 26,000 descriptors and...
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CAS Registery Numbers

Have you ever met a chemist?  I find that chemists are some of the most organized, meticulous people I know.  I attribute it to the fact that if they’re not careful they’re apt to blow themselves up in lab (although some of them do have a pyromania and enjoy setting things on fire on purpose). So true to their organized selves, chemists have assigned a unique number to every chemical substance that is recorded in literature.  Every chemical substance!  That’s more than 66 million substances.  About 15,000 new substances are added each day.  (I wonder if they take the...
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Presenting your Data

Now that you have decided how to organize your data, how do you present it?  Today’s information is based in part on A.V. Abela‘s popular Chart Chooser diagram which is also available in an interactive form.  Although the chart chooser was designed for presentations, it is handy for papers also.  My main point is you need to know what kind of argument you are presenting with your data.  My second point is that most people can interpret comparisons better than absolutes so you need a reference point for your data.  For example, is 80° a hot or cold day? ...
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Organizing Data in your Paper

Last time, I mentioned that if you have multiple experiments that you should decide on an order and then stick to that order.  So how do you decide on an order?  Let’s say this is your data You might decide to order it by shape (squiggles, ovals, diamonds) and then by number (one, two, three). Or maybe the other way around by number and then by shape.     Or maybe you decide to order it by color (red, green, purple) and then by shading (empty, solid, striped).  Or by shading then color. Or by shape and then shading...
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Writing and Fractals

Last time I mentioned that the four main parts of a scientific article are Introduction, Methods, Results, and Conclusions.  This is all fine and dandy when you’re writing a 12-20 page paper, but what if you’re writing something longer like a thesis? I like to think of writing longer papers in terms of fractals.  As you might know, fractals are self-similar which means that the look the same (or nearly the same) at every scale.  So if we take take a pattern like thisand then repeat the same pattern on every segment like this, we get this Now let’s...
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Scientific Papers and the Research Process

Since the last four posts were on databases, I thought I would spend the next four posts on scientific writing.  Today, I start with the basics:  the structure of a scientific paper. Scientific papers follow an idealized form of the scientific research process. Pick a topic and learn as much as can about what has been done. Figure out the next step that needs to be taken. Formulate a hypothesis (if A, then B) that addresses that next step. Design an experiment to test the hypothesis. Run the experiment. Collect data. Reduce data. Analyze data. Draw conclusions. Suggest future...
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Searching Databases and Driving Cars

With the plethora of databases comes a variety of different interfaces. Some databases might use be accessed using different interfaces. Some interfaces can access more than one database. Most people are creatures of habit:  they find a database they like (usually an important one in their field) and get used to it.  When they have to search another database (or if the database has been bought out by another company), they can often find the different interface confusing.  As a result they sometimes simply don’t conduct the search. I like to assure people that searching in an unfamiliar interface...
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