All Free Statistics MCQs with Answers
Every Statistics question in the bank, across all chapters, each with the correct answer and a written explanation. Free and unlimited, with no account needed.
545 questions · page 27 of 55
261. Statistics are ___________ expressed?
- A. Descriptive
- B. Ability
- C. Qualitatively
- D. Quantitatively
Explanation: Statistics deals with numerical facts, so statistical information is expressed quantitatively. Qualitative descriptions may be converted into categories or numbers, but they are not statistics in their original form.
Correct answer: Quantitatively262. Confidence interval should be ___________?
- A. Shorter
- B. Wider
- C. Large
- D. Small
Explanation: For a fixed confidence level, a shorter confidence interval is preferred because it gives a more precise estimate of the population parameter. Increasing confidence generally makes the interval wider, so both goals cannot be maximized simultaneously.
Correct answer: Shorter263. Confidence interval is a measure of?
- A. Accuracy
- B. Precision
- C. Error
- D. All of above
Explanation: A confidence interval expresses the precision of an estimate by showing a range of plausible parameter values. Accuracy concerns closeness to the true value, which cannot be guaranteed merely by calculating an interval.
Correct answer: Precision264. A quantity obtained by applying certain rule or formula is known as ________________?
- A. Estimate
- B. Test Statistics
- C. Estimation
- D. Sample
- E. Estimator
Explanation: An estimate is the numerical quantity produced after an estimator, such as a formula or rule, is applied to sample data. The estimator is the rule itself, not the resulting quantity.
Correct answer: Estimate265. Parameter is a _________ quantity?
- A. Constant
- B. Variable
- C. All of above
- D. Non of these
Explanation: A parameter describes a population and has one fixed value, even though that value is usually unknown. A sample statistic, by contrast, can vary from sample to sample.
Correct answer: Constant266. If n = 400 and P=.69 then 90% C.I for P is _________________?
- A. 652 and . 728
- B. .314 and .652
- C. .798 and .745
- D. None of these
Explanation: For a proportion, the 90% interval is p ± 1.645√[p(1−p)/n]. Substituting p = .69 and n = 400 gives approximately .69 ± .038, or .652 to .728.
Correct answer: 652 and . 728267. 95% confidence limits u are ________________?
- A. x±1.65 6/√n
- B. u±1.95 S/√n
- C. x±1.96 6/√n
- D. ±1.96 6/√n
Explanation: For a 95% large-sample confidence interval for μ, use x̄ ± 1.96σ/√n. The value 1.65 corresponds approximately to a 90% two-sided interval, while 1.95 is not the standard critical value.
Correct answer: x±1.96 6/√n268. _________ is an estimate expressed by a single value?
- A. C.I.
- B. Point estimator
- C. Parameter
- D. Point estimate
Explanation: A point estimate reports an estimated parameter as one numerical value, such as x̄ = 40. A confidence interval gives a range rather than a single value.
Correct answer: Point estimate269. x=40 is estimator of _________________?
- A. (U)
- B. 6
- C. Ux
- D. 6/√n
Explanation: If x̄ = 40 is used to estimate the population mean, its target is μ. The symbols in the other choices refer to different parameters or to a standard-error expression.
Correct answer: (U)270. Sample proportion P is __________ estimator?
- A. Biased
- B. Parameter
- C. Unbiased
- D. None of these
Explanation: For a random sample, the sample proportion p̂ has expected value equal to the population proportion P, so it is unbiased. This makes it an estimator, not the population parameter itself.
Correct answer: Unbiased