'number of seats in a car' is an example of which data type?
Numerical discrete
Determine if the following variables are Numerical or Categorical data types: 'plays sport' and 'gender'.
both categorical variables
For the least squares regression line y = 1.2 - 0.52x
Determine the gradient
-0.52
State the three types of transformations
Squared, reciprocal and log
The number of bathing suits sold one summer is 432. The deseasonalised number is closest to:
240
The percentage segmented bar chart shows the distribution of hair colour for 200 students.
The number of students with brown hair is closest to:
72
The scatterplot shows the weights at age 21 and weight at birth of 12 women. The association is best described as a:
moderate positive linear
Determine the y-intercept from the graph.
80
The aim of transforming data is to?
Create a more linear data set. Which will allow for more accurate predictions.
Determine the 3 trends/features of this time series graph
Decreasing Trend, Seasonality, Irregular Fluctuations.
The shape of the histogram is best described as?
Positively skewed with an outlier
The association between 'weight at age 21' and 'weight at birth' is found to be positive and linear, with a correlation coefficient of r=0.58.
Determine the coefficient of determination.
34%
Determine the explanatory variable in the equation:
days of rain
Determine the transformations that can be applied to this data
y2, log x, 1/x
The three-moving mean for time period 2 is?
3.4
Find the number with the log value equal to 2.314
206
We wish to investigate the association between the variables weight (in kg) of young children and level of nutrition (poor, adequate, good).
The most appropriate graphical display would be?
parallel boxplots
The least squares regression line: y = 8 - 9x
Predicts that when x = 5, the value of y is?
- 37
The effects of a squared transformation is to …
stretch the high values in the data
This missing value is?
0.8
A student's mark on a test is 50. The mean mark for their class is 55 and the standard deviation is 2.5. Their standard score is?
-2
Is there an association between 'conversation test scores' and 'Completed weeks of course'?
Yes
Using a least squares regression line, the predicted value of a data value is 78.6.
The residual value is −5.4. Determine the actual data value.
73.2
The association between the hours spent studying for an exam and the mark achieved is:
mark = 20 + 40 × log (hours)
Predict the students 'mark' who studies for 20 hours.
72
Using this data, the seasonal index for autumn is?
0.82