Interpretation of Data Questions and Answers

Answer: C

The lowest level scale is the nominal scale.

Stevens's four levels of measurement, from lowest to highest, are nominal, ordinal, interval and ratio. A nominal scale only names or classifies, such as gender, religion or blood group. The numbers attached have no order or size, so only counting and the mode can be used.

The ordinal scale adds rank order, the interval scale (printed 'Internal scale') adds equal distances between values, and the ratio scale adds a true zero, which makes it the highest level.

Answer: D

It indicates confidence about generalizing their finding from the sample to the population.

A test of significance asks how likely it is that a result found in the sample, such as a difference or correlation, arose by chance from sampling. A significant result, for example at the 5 per cent level, lets the researcher infer with stated confidence that the result holds in the population from which the sample was drawn.

Inter-coder reliability is measured with agreement statistics such as Cohen's kappa, and understanding bivariate and multivariate analysis is a matter of method, not of testing. Passing the driving test is an unrelated distractor.

Answer: D

Mean, median and mode are measures of central tendency.

Each gives a single typical value around which the data cluster. The mean is the arithmetic average, the median is the middle value when the data are arranged in order, and the mode is the most frequent value.

Measures of deviation (dispersion), such as range, standard deviation and variance, describe the spread of data. Measures of association, such as correlation coefficients, describe the relationship between two variables, and ways of sampling, such as random or stratified sampling, are methods of selecting cases, not summary statistics.

Answer: C

The curve is a Hyperbola.

For every point the product XY is the same: 1 x 60 = 2 x 30 = 3 x 20 = 4 x 15 = 5 x 12 = 60. So the points lie on XY = 60, that is \(Y = \frac{60}{X}\), a rectangular hyperbola: Y is inversely proportional to X.

A straight line needs equal changes in Y for equal steps in X (here they are 30, 10, 5, 3). Y falls but not by a constant ratio (30/60 = 0.5, 20/30 = 0.67), so it is not exponential, and a parabola would turn upward again.

Answer: D

The difference is the same in 1961 and 1971.

Subtract the death rate from the birth rate for each year: 1961: 90 - 20 = 70; 1971: 88 - 18 = 70; 1981: 82 - 17 = 65; 1991: 78 - 16 = 62; 2001: 75 - 14 = 61; 2011: 70 - 12 = 58; 2021: 60 - 10 = 50.

Only 1961 and 1971 share a difference, 70 per thousand. The pairs 2011-2021 (58, 50), 2001-2011 (61, 58) and 1971-1981 (70, 65) all differ.