ICS Part 2 Statistics Chapter 12 Online Test

By increasing the sample size, the precision of confidence interval is:

• Decreased A
• Increased B
• Constant C
• Unchanged D

Level of significance is denoted by

• 2 - α A
• 3 - α B
• α C
• 1 - α D

If (1-α) is increased, the with of a confidence interval is:

• Decreased A
• Increased B
• Constant C
• Same D

Statistical inference has two branches namely:

• Level of confidence and degrees of freedom A
• Biased estimator and unbiased estimator B
• Point estimate and interval estimate C
• Estimation of parameter and testing of hypothesis D

If population proportion (P) is unknown, the standard error of the sample proportion (p) can be estimated by the formula

• 
  A
• 
  B
• 
  C
• 
  D

Large sample contains more than

• 5 values A
• 10 values B
• 20 values C
• 30 values D

The distance between an estimate and the estimated parameter is called:

• Sampling error A
• Standard error B
• Bias C
• Error of estimation D

A single value used to estimate a population value is called:

• Interval estimate A
• Point estimate B
• Confidence interval C
• Level of confidence D

Confidence intervals which are often used in practice are

• 90% A
• 95% B
• 98% C
• all of these D

A range of values used to estimate an unknown population parameter is

• a point estimator A
• An interval estimator B
• an unbiased estimator C
• A biased estimator D

The process of making estimates about the population parameter from a sample is called:

• Statistical independence A
• Statistical inference B
• Statistical hypothesis C
• Statistical decision D

The precision can be increased by  ---------------- the sample size

• increasing A
• decreasing B
• changing C
• ignoring D

If 1-α = 0.90, the value of Z_a/2 is:

• 1.645 A
• 1.96 B
• 2.326 C
• 2.575 D

Types of statistical inferences are

• one A
• two B
• three C
• four D

The following statistic are unbiased estimators:

• The Sample mean A
• S² = Σ(X - X)²/n-1 B
• The sample proportion C
• All the above D

• best estimators A
• biased estimators B
• unbiased estimators C
• normal estimators D

If mean of the sampling distribution is equal to the parameter then the estimator will be

• biased A
• consistent B
• sufficient C
• unbiased D