In the following passage, some words have been deleted. Read the passage carefully and select the most appropriate option to fill in each blank. The Human Development Index (HDI) is a summary (1) _________ of average accomplishment in important areas of human development, (2) _________ living a long and healthy life, being informed and having a good quality of living. The HDI is the geometric mean of the normalised (3) _________ for each dimension. The health component is (4) _________ by life expectancy at birth, while the education dimension is measured by the average number of years of schooling for individuals aged 25 and above, as well as the (5) _________ number of years of schooling for school-age children.
Select the most appropriate answer for blank number 3.
- (a)contents
- (b)indices
- (c)glimpses
- (d)features
Answer
Why
Correct — B. The sentence says the HDI is the geometric mean of the normalised ______ for each dimension. A geometric mean is taken of numbers, so the blank has to name numbers.
Indices is the plural of index, and an index is a number that rescales a raw measure onto a comparable scale. Normalised indices is the phrase the sentence is reaching for.
Contents, glimpses and features all name parts or impressions, and none of those can be normalised or averaged. Option (b).
Why the others are wrong
- (a)contents — Contents means what something contains, a list of parts. Contents cannot be normalised, and you cannot take a geometric mean of them.
- (c)glimpses — A glimpse is a brief look at something. It names an act of seeing rather than a quantity, so it cannot be rescaled or averaged across dimensions.
- (d)features — Features are characteristics. Characteristics are described, not placed on a scale — the sentence needs the numbers that go into the mean.
Concept
This blank is decided by collocation and arithmetic together.
Geometric mean names a mathematical operation, so whatever fills the gap must be a set of numbers. That single requirement removes every option that names a quality or an impression.
Index is the standard term for a number that rescales a raw measure onto a comparable scale, and its plural in statistics is indices. Normalised, immediately before the blank, points the same way: only a number can be normalised.
Indexes is also a correct plural of index in general English, but indices is the form used for statistical and mathematical measures, which is the register this passage is written in.
Key facts
- Indices is the plural of index used for statistical and mathematical measures.
- In the HDI, each dimension index is rescaled onto a common 0-to-1 scale before the geometric mean is taken.
- A geometric mean multiplies n values and takes the nth root, so its inputs have to be numbers.
Study next
Common traps
- Choosing Features because the dimensions really are characteristics of development.
- Skipping over the words geometric mean, which are the clue that numbers are wanted.
- Rejecting Indices as an unfamiliar word rather than recognising it as the plural of index.
In this cloze the vocabulary blanks are worked from the words immediately around the gap — here normalised and geometric mean do the whole job, and knowing what the HDI is remains optional.
Blank 1 of this same passage, at English Q.21, is decided the same way, by the frame a summary ______ of.
Related PYQs
No directly related past PYQ was found.