Hello :)! I really need some help with these True/False questions.. Please could you help me :)

State whether the following statements are true or false.

QUESTION 1

A qualitative variable for which there is some kind of ranking for the different values is called an interval variable.

QUESTION 2

In general, probability samples are samples in which the elements to be selected are drawn on the basis of probability in such a way that each element in the population has the same probability of being selected obtained as part of the sample.

QUESTION 3

All the individual data values can be read out from a stem-and-leaf display.

QUESTION 4

As a result of surveying 1000 first year students at UNISA, it was found that 32% owned a laptop. The value 32% is an example of a parameter.

QUESTION 5

A histogram can be used to summarize ordinal qualitative data.

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QUESTION 6

The interquartile range of a data set is always half of the range of the data set.

QUESTION 7

Measures of position are used to describe the position a specific data value possesses in relation to the mean of the data.

QUESTION 8

Bias in self-selected sampling can be reduced by increasing the sample size.

QUESTION 9

Assume that the least squares line fitted trough a scatter diagram of two variables, X and Y; is given by by D 5:2 0:3x: Then the coefficient of correlation for the two variables is negative.

QUESTION 10

The coefficient of correlation for a data set with two variables is always smaller than the covariance of the same data set.

QUESTION 11

A data set can have several mode values.

QUESTION 12

The median of a data set is always equal in value to one of the original data values.

QUESTION 13

A box plot is plotted using the values of the mean, the first quartile and the second quartile.

QUESTION 14

Sampling error can be reduced by increasing the sample size.

QUESTION 15

Cluster sampling is an example of simple random sampling.

QUESTION 16

If a data set consists of only negative values, then its standard deviation is negative.

QUESTION 17

If a distribution is symmetric, then the distance between first and second quartiles if roughly the same as the distance between the second and third quartiles.

QUESTION 18

In a simple random sample, all members of the population have the same probability of being selected.

QUESTION 19

A positively skewed data set is one where most of the values are positive.

QUESTION 20

If the covariance between two data variables is zero then the scatter diagram shows all the points lined along a horizontal line.