Using equivalent samples, a researcher obtained a significant correlation 95 times out of 100 trials. He/She decided to reject the null hypothesis. The alpha level would be :
Cannot be determined from the information given
Alpha is the prespecified significance threshold controlling Type I error under the null model. Finding significance in 95 of 100 trials does not reveal that threshold. If an alternative is true, the rejection frequency relates to power; it is not correct to calculate alpha as 1 − 0.95.
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 scale
Set 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 minute
For scores drawn from a continuous reference distribution, what is the shape of the distribution of their percentile ranks?