Are Stanines based on the bell curve?

Stanines are also similar to normal distributions. You can think of these scores as a bell curve that has been sliced up into 9 pieces. However, where a standard normal distribution has a mean of 0 and a standard deviation of 1, stanines have a mean of 5 and a standard deviation of 2.

What does standard score and percentile rank mean?

Some assessments assign the average result for the test a standard score of 100, and assign higher and lower scores accordingly. A percentile rank of 50 means the student performed better than 50% of the children her age who took the same test – also an average result.

What do Pat Stanines mean?

Scale scores at each year level nationally are divided into nine levels of achievement, called stanines, with the lowest performance level being stanine one and the highest stanine nine. Since the average stanine is stanine five, this indicates an above average performance.

What is Stanines in assessment?

Stanine(STAndard NINE) is a method of scaling test scores on a nine-point standard scale with a mean of five (5) and a standard deviation of two (2). Test scores are scaled to stanine scores using the following algorithm: Rank results from lowest to highest.

How are Stanines calculated?

Calculation of Stanine Scores The first 4% of ranked scores (raw scores 351-354) will be given a stanine score of 1. The next 7% of ranked scores (raw scores 356-365) will be given a stanine score of 2. The next 12% of ranked scores (raw scores 366-384) will be given a stanine score of 3.

What is the difference between stanine and percentile?

The stanine scale is a normalized standard score scale consisting of nine broad levels designated by the numbers one through nine. A percentile rank indicates the percentage of students in the same age group whose scores fall below the score obtained by a particular student.

What is the mean score on a bell curve?

On the bell curve, the Mean is in the middle, at the 50th percentile. The average or Mean score on most tests is 100 (Mean = 100). Tests are made up of subtests. The Mean is usually 10 on subtests (Mean = 10). What are Standard Deviations?

Which is more accurate a stanine or a percentile?

Although stanines are less precise than percentiles, in many ways they reflect the bell curve much more. If you recall, the purpose of a standardized test’s norm group is to plot the scores on a bell curve and then draw comparison scores thereafter. The normal bell curve with its distribution can be referenced above.

Why are stanines in the middle of the bell curve?

The normal bell curve with its distribution can be referenced above. Looking closely at the bell curve distribution, you will notice that the 4th, 5th and 6th stanines include a large range of percentile scores. This reflects the fact that the bell curve is tallest in that middle range: that those ranges represent the most students.

Why does the bell curve rise over 60 percentiles?

This means that 98 percent of the population of people your age are taller than you are. The bell curve rises up over the 40-60 th percentiles because most people score within this range. (i.e. most people are medium-sized if we use height as an example)