# In observational studies the researcher manipulates

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In observational studies the researcher manipulates the experiment and observes the results closely.
Descriptive statistics are used to make inferences about the population. FalseA fundamental property of a nominal scale is equivalence. TrueIt is standard practice to carry all intermediate calculations to four more decimal places than will be reported in the final answer. FalseAn ordinal scale possesses the attributes of magnitude and equal interval. FalseIf IQ was measured on a ratio scale, and John had an IQ of 40 and Fred an IQ of 80, it would be correct to say that Fred was twice as intelligent as John. True
In a race, Sam came in first and Fred second. Determining the difference in time to complete the race between Sam and Fred involves an ordinal scale TrueDetermining the number of students in each section of introductory psychology involves the use of a ratio scale. TrueNominal scales can be used either qualitatively or quantitatively.
In rounding, if the remainder beyond the last digit is greater than 1/2, add one to the last digit. If the remainder is less than 1/2, leave the last digit as it is. TrueA discrete variable requires nominal or interval scaling. TrueOne generally has to specify the real limits for discrete variables since they cannot be measured accurately. FalseMeasurement is always approximate with a continuous variable.
Most scales used for measuring psychological variables are eitherratio or interval. FalseAll scales possess magnitude, equal intervals between adjacent units, and an absolute zero point. FalseThe average number of children in a classroom is an example of adiscrete variable. FalseWhen rounding, if the decimal remainder is equal to and the last digit of the answer is even, add 1 to the last digit of the answer. FalseClassifying students into whether they are good, fair, or poor speakers is an example of ordinal scaling. TrueWhen a weight is measured to 1/1000th of a gram, that measure is absolutely accurate. False
An interval scale is like a ratio scale, except that the interval scale doesn’t possess an absolute zero point. TrueS X2 and (S X)2generally yield the same answer. FalseWith nominal scales there is a numerical relationship between theunits of the scale. FalseIf the quantity X= 400.3 for Nobservations, then the quantity Xwill equal 40.03 if each of the original observations is multipliedby 0.1. True