A random sample of 100 independent observations has mean 100. The population standard deviation is known to be 20. Using the normal approximation, which interval is the approximate two-sided 99% confidence interval for the population mean (significance level 0.01)?
Population mean falls between 94.8 to 105.2
Standard error = 20/√100 = 2. The 99% normal critical value is approximately 2.576, so the interval is 100 ± 2.576 × 2 = (94.848, 105.152), rounded to 94.8–105.2. The confidence level describes the long-run coverage of this interval procedure.
Important Questions from Measurement and Analysis of Data - Teaching
Type II error in hypothesis testing is:
Which level of measurement is least used in educational psychology?
In List I types of variables are given and in List II correlation coefficients related to them are given. Match List I and List II and choose the correct answer from the code given below.
List I
(Types of variable)
List II
(Correlation coefficient)
a) Both variables continuous i) Biserial b) Both with ordinal measure ii) Pearson's 'r' c) Both with artificial dichotomy iii) Contingency coefficient d) One continuous and other with artificial dichotomy iv) Spearman's rho e) Two or more categories v) Tetrachoric 'r' vi) Point-Biserial Match the measurement scales in Set I with the examples in Set II.
Set I
(a) Nominal scale
(b) Ordinal scale
(c) Interval scale
(d) Ratio scaleSet II
(i) Ranking students’ performances in musical events
(ii) Spelling-test scaled scores defined with equal units and an arbitrary zero
(iii) Classifying students by the type of co-curricular activity they participate in
(iv) Students’ writing speed in words per minuteFor scores drawn from a continuous reference distribution, what is the shape of the distribution of their percentile ranks?
