IX. Say whether the following statements are true or false. Extend your ideas

1. Economists often find it more convenient and revealing to plot data on charts as this highlights important stories hidden in the data.

2. The retail price index provides a measure of the cost of living, obtained as the weighted average of different commodity prices.

3. Real wage rates are calculated by adjusting nominal wage rates for changes in the cost of living.

4. Economic models help to explain the scatter and serve to remind us of which other things are being held equal.

5. The process of devising an economic model can’t be conducted independently of the data.

6. The measurement ‘at current prices’ is known as the nominal value.

7. The evaluation of models is often straightforward in economics.

8. The position of a nonlinear relationship can’t be affected by changes in the background ‘other things equal’ factors.

9. Index numbers are frequently used by economists to compare variables measured in similar units.

10. Well-known and widely publicized indices include the retail price index and the index of industrial production.

X. Insert the appropriate prepositions where necessary:

1. Low fares charged by the tube service bring ______(1) extra revenue _______(2) the company.

2. Fare multiplied _____ (3) number of passengers equals _____(4) total fare collection.

3. Other factors can influence ______(5) the number of passengers who prefer to travel by this means of transport.

4. Not all determinants should be taken______(6) account since we consider the model.

5. Raising wages is not sufficient to compensate _____(7) the rocketing inflation rate.

6. Will we abandon cars _____(8) favour ____(9) public transport?

7. Forecasts cannot capture the full detail of the underlying system, so they rely _____ (10) approximate equations.

8. The quality of the measurement instruments should only be checked _______(11) the initial data analysis phase when this is not the focus or research question of the study.

9. Time series analysis comprises ______(12) methods for analysing time series data in order to extract meaningful statistics and other characteristics of the data.

10. Time series data have a natural temporal ordering. This makes time series analysis distinct ______ (13) other common data analysis problems, in which there is no natural ordering of the observations.

11. However, empirical investigations can indicate the advantage of using predictions derived _____ (14) non-linear models, _____(15) those from linear models.

XI. Read the text and choose the correct word or words from A, B, C or D to fill in each gap: