Tag: moving averages

Questions Related to moving averages

Bira and his wife Sheena have two daughters aged $12$ and $16$. Sheena's mother and father, aged $65$ and $72$, also live with them. Bira is currently looking for work, but can't find any. His elder daughter completed class $10$ and prefers to look for work. Sheena prefers to stay at home to look after house works. How many unemployed members does Bira's family have?

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  1. $1$

  2. $2$

  3. $3$

  4. $4$

Show answer
Correct Option: B
Explanation:

Only Bira and his elder daughter can be called unemployed as per the given situation.

A qualitative forecast

statistics moving averages moving average and variation simple moving average uses of average in day-to-day life introduction to time series introduction to time series and forecasting

  1. predicts the quality of a new product.

  2. predicts the direction, but not the magnitude, of change in a variable.

  3. is a forecast that is classified on a numerical scale from $1$ (poor quality) to $10$ (perfect quality).

  4. is a forecast that is based on econometric methods.

Show answer
Correct Option: B
Explanation:

Qualitative forecast is an estimation methodology which uses expert judgment, rather than numerical analysis. It predicts the direction, but not the magnitude of change in variable.

Two pipes A and B can fill a tank in 20 and 30 minutes respectively. If both the pipes are used together, then how long will it take to fill the tank?

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  1. $12 min$

  2. $15 min$

  3. $25 min$

  4. $50 min$

Show answer
Correct Option: A
Explanation:

$\displaystyle \frac{1}{20} + \frac{1}{30} = \frac{1}{x}$
$\displaystyle \frac{5}{60} = \frac{1}{x}     \Rightarrow 12 min$

The first step in time-series analysis is to

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  1. perform preliminary regression calculations.

  2. calculate a moving average.

  3. plot the data on a graph.

  4. identify relevant correlated variables.

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Correct Option: C
Explanation:

The first step in time series analysis is to plot the data on a graph.

In moving average method, we cannot find the trend values of some:

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  1. Middle periods

  2. End periods

  3. Starting periods

  4. Between extreme periods

Show answer
Correct Option: D
Explanation:

In moving average method, we cannot find the trend value of some:between extreme periods.

Which of the following is not one of the four types of variation that is estimated in time-series analysis?

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  1. Predictable

  2. Trend

  3. Cyclical

  4. Irregular

Show answer
Correct Option: A
Explanation:

Four types of variations estimated in time-series analysis are :-

1. Trend
2. Seasonal
3. Cyclical
4. Irregular

Hence, A) Predictable is the correct option

The unsystematic sequence which follows irregular pattern of variations is called:

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  1. Noise

  2. Signal

  3. Linear

  4. Non-Linear

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Correct Option: A
Explanation:

By definition,
Noise is a component of time series which is the unsystematic sequence which follows irregular pattern of variations

A time series consists of:

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  1. Short-term variations

  2. Long-term variations

  3. Irregular variations

  4. All of the above

Show answer
Correct Option: D
Explanation:

$\Rightarrow$  A time series consist of $Short-term\,variations,\,Long-term\,variations\, and\, Irregular\,variation.$

$\Rightarrow$  $Short \,term\, variation -$ Seasonal trends are short term movements occurring in data due to seasonal factors. For example,  it is commonly observed that the consumption of ice-cream during summer is generally high and hence an ice-cream dealer's sales would be higher in some months of the year while relatively lower during winter months.
$\Rightarrow$  $Long\,term\, variation -$ The secular trend is the main component of a time series which results from long term effects of socio-economic and political factors. Prices and export and import data, for example, reflect obviously increasing tendencies over time.
$\Rightarrow$  $Irregular\,variation-$These are sudden changes occurring in a time series which are unlikely to be repeated. They are components of a time series. Floods, fires, earthquakes, revolutions, epidemics, strikes etc., are the root causes of such irregularities

Depression in business is:

business mathematics and statistics moving averages introduction to time series introduction to time series and forecasting time series and forecasting uses of average in day-to-day life

  1. Secular trend

  2. Cyclical

  3. Seasonal

  4. Irregular

Show answer
Correct Option: B
Explanation:

$\Rightarrow$  Depression in business is : $Cyclical $.

$\Rightarrow$  Depression phase - The depression or trough is the bottom of a cycle where economic activity remains at a highly low level. Income, employment, output, price level, etc. go down. 
$\Rightarrow$  A depression is generally characterized by high unemployment of labor and capital and a low level of consumer demand in relation to the economy’s capacity to produce. 
$\Rightarrow$  This deficiency in demand forces firms to cut back production and lay-off workers.

An orderly set of data arranged in accordance with their time of occurrence is called:

business mathematics and statistics moving averages introduction to time series introduction to time series and forecasting time series and forecasting uses of average in day-to-day life

  1. Arithmetic series

  2. Harmonic series

  3. Geometric series

  4. Time series

Show answer
Correct Option: D
Explanation:

From the definition of Time series,

Time series is an orderly set of data arranged in accordance with their time of occurrence.