Archive for October, 2011

A Question Of Sample Size

October 31, 2011

By Nirmaldasan

Three samples are usually considered to be enough for testing the readability of a text. Whether the chosen sample is representative depends on the sample size. Interestingly, different formulae require different sample sizes.

The Winnetka formula, created by Mabel Vogel and Carleton Washburne in 1928, requires a sample of 1000 words. The Lorge Readability Index (1944), Flesch Reading Ease (1948), Gunning’s Fog Index (1952) and Fry Graph (1977) require a sample of about 100 words. Harry McLaughlin’s SMOG (1969) uses a 30-sentence sample. The FORCAST formula of FORd, CAylor and STicht (1973) needs a sample of 150 words. The new Dale-Chall formula (1995) needs an exact 100-word sample.

Since a formula is only a statistical tool that calculates the approximate grade level of a representative sample, it follows that a shorter sample is most likely to yield an inaccurate result. Testing the full text or choosing larger samples may guarantee better results. However, Harris-Sharples found that a ‘minimum of eight samples produced readability scores similar to the largest samples’, according to Jeanne S. Chall and Edgar Dale (Appendix A of Readability Revisited: The New Dale-Chall Readability Formula).

But what is the optimal sample size? A 1000-word sample is easier to test than a full text; a 100-word sample reduces the task by a tenth; and a 10-word sample would be tempting indeed for those who want quick results. Let us try, though on a small scale, to find out the optimal sample size for calculating semantic complexity, which is usually determined by the length of the words in a text.

I picked up Roald Dahl’s Matilda and calculated the average number of syllables per word (ASW) on a sample of the first 1000 words of Chapter I (The Reader Of Books). There were 1376 syllables and, therefore, ASW = 1.376. I then divided the 1000 words into 10 samples, each of 100 words, and found that the ASW varied from 1.3 to 1.46. Next, I divided the first 100 words (ASW = 1.42) into 10 samples, each of 10 words, and found that the ASW varied from 1 to 1.6.

Samples of 10 words vary too much, but samples of 100 words appear more stable. Perhaps this explains why many readability formulae use 100-word samples. Clearly, the calculation of semantic complexity with a 10-word sample cannot be recommended.


Storybooks For Kindergarten

October 1, 2011

By Nirmaldasan


Glenn Doman, author of How To Teach Your Baby To Read, says: “Two years of age is the best time to begin if you want to expend the least amount of time and energy in teaching your child to read.” The child needs to be taken through seven steps, beginning not with the alphabet but with visual differentiation. Doman suggests an initial list of 59 words and explains how these words have to be taught patiently one at a time. Here’s the list:

The ‘Self’ Vocabulary

hand, knee, foot, head, nose, hair, lips, toes, leg, eye, ear, arm, teeth, belly, mouth, elbow, thumb, finger, tongue, shoulder.

The ‘Home’ Vocabulary

  1. Family:

mommy, daddy, brother, sister, dog, cat, fish, bird, baby

  1. Objects:

Chair, table, door, window, wall, bedroom, bathroom, kitchen, refrigerator, tv

  1. Possessions:

Plate, spoon, cup, hat, shoes, ball, orange, pants, dress, pajamas

  1. Doing:

Sitting, standing, running, laughing, climbing, creeping, walking, jumping, throwing, reading.

Only in the sixth step the child will be ready to read a real book. Doman writes: “The choice of the book to be used is very important and should meet the following standards:

  1. It should have a vocabulary of not more than 150 different words.
  2. It should present no more than a total of 15 or 20 words on a single page.
  3. The printing should be no less than ¼” high.
  4. Text and illustrations should be separated as much as possible.”

“There are three distinct levels of understanding in the process of learning how to read,” says Doman. First, the child discovers that words have meaning. Second, the child notices that words combine with other words. Third, the child realizes that the book is actually talking to him/her.

Doman recommends 26 books, including some written by Dr. Seuss, which fulfilled the following criteria: “1. large enough print; 2. print not intertwined with pictures; 3. size of vocabulary; and, 4. subject matter.”

Teachers may follow Doman’s guidelines in picking suitable storybooks for their children in kindergarten.