I posted this message 5 and 1/2 years ago on Rootsweb message board... it is still pertinent and really applies researching many other places and documents I was subsiquently picked up by Olive Tree Genealogy Blog, which is free and has many useful tips to help with your researchhttp://olivetreegenealogy.blogspot.com/
Since the subject was brought up about searching Ellis Island I thought I would give some insight into what I have found.
First let me say that for over a year now I have not used the "regular" Ellis Island org site, even though I am a member. I have found that the web page that Dr Morse has created is much superior, allowing a better chance to find your "missing immigrant".
Here is a link to his site. http://stevemorse.org/ellis2/ellisgold.html
1. Transcibed data base online
The greatest problem I have found is in the modern day transcribing of the data base. Many manifests are difficult to read and letters can be mistaken for the wrong letter.
S & L
Some common errors were made when transcribing names beginning with the letter S. For instance if I do a search for the name LJUBANOVIC the search finds 39. However if I enter enter SJUBANOVIC the search finds 5 and... upon examination of the manifest they are all in fact spelled LJUBANOVIC.
u and n
Using the same surname as in example (a) I now will search for names beginning with LJ. The search finds 6 LJNBANOVIC and looking at the original ship manifest finds they are all in fact LJUBANOVIC. So instead of the original 39 found there are in fact 50 records for LJUBANOVIC immigrants.
c and e
For this example I'll use the name KATIC. A search finds 288. However if we use a "Begins with search" KAT we will find another 13 mistakenly transcribed as KATIE, once again the manifests show KATIC.
c and o
The "Begins with" search for KATI finds 1 KATIO. In fact the manifest shows the spelling to be KATIC. So instead of 288 KATIC immigrants Ellis Is had 302 with that surname pass through the gates!
a and o
Again using KATIC, I changed the spelling for the search to KOTIC. Now this one is tricky as both surnames exist. The search found 9. Of those 9 there are in fact 3 that are KATIC.
K and R
Searching for RATIC found 11 entries. While I did not lookt all the manifests I did find at least one that was in fact KATIC. To verify this we can simply look at other
entries on the manifest and will find the manifest authors Karolina entry where the K looks just like his entry for what the transcribers saw as RATIC.
r and z
One example of this transcribing error can be found with the name KNEZOVIC. There are some transcribed as KNEROVIC but examination of the manifest shows they are in fact KNEZOVIC
y and z
Example KNEZEVIC are sometimes mis-transcribed as KNEYERIC.
In the case of some Croatian surnames the Croatian V, which sounds like the English V, that is vee, has been replaced on some manifests with W. This could be a German influence of either the manifest author or the owner of the surname, as the German W sounds like vee. Example: MIHALJEWIC, which should be MIHALJEVIC. Maybe the manifest author was of German background or the owner thought that the foreign spelling would be chic
given name surnames reversed
The typical manifest had the given name first surname last. However some had surname first. That along with the unfamiliar names (unfamiliar to the volunteer transcribers) made the job of transcribing a challenge. Using KATIC as a given name last name beginning with M, finds 5 immigrants. In fact the surname on 4 of those is KATIC. One manifest the author appears to have alternated between having the given name first, while other entries the surname was first!
2. Wrong spelling on the manifest
While most names were written on the manifest correctly I have found a few with minor errors. However those minor errors are enough to cause one to miss an immigrant in a search. Here is the first example I found searching for Croatian surnames, MIHALJEVIC. Using a begins with MIHALJE we will find 2 listings for MIHALJEVIZ, a non-existant spelling. The manifest clearly shows MIHALJEVIZ, which is wrong. I noticed that they both departed from Le Havre, France. And since have found other Croatians traveling out of French ports had their surnames misspelled with a IZ instead of the correct IC.
It if important to try many variants of the surname as possible to find your immigrant. Also remember to enter the given name as a surname when searching. Another tip is to learn something about the language and naming customs of the
ethnic group of the person you are searching for. This is important as we generally think in English. I know that this is important from my Croatian research. Often times people are searching for someone named John or George or Mary... those names do not exist in Croatian with those spellings! However for John we can search for Ivan or Ivo, George may be Juraj or Jure and Mary could be Marija, Mara or Marica.