The Standardized Score

The standardized score is a statistical tool thatallows comparison of related quantities that are normallydistributed. A very good use is test scores. When a student wishes tocompare their own results with everybody elses, they may stanaridizetheir scores to find the percentile in which they lie.

Suppose one student recorded his marks in a set ofexams and collected the mean and standard deviation of all the othermarks of the other students.

Subject

Score,

Mean,

Standard Deviation,

Maths

78

72

10

English

80

83

12

Physics

65

70

15

Chemistry

80

60

10

Biology

79

65

17

The standard score is given by

For mathsFromtables, 72.57% of scores were lower.

For englishFromtables, 59.87% of scores were lower.

For physicsFromtables, 62.8% of scores were lower.

For chemistryFromtables, 97.72% of scores were lower.

For biologyFromtables, 79.49% of scores were lower.

In order of decreasing performance his results were chemistry,biology, maths, physics and english.