Commerce MCQs
Topic Notes: Commerce
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
191
Which function is utilized in the calculation of the Mann-Whitney U-test?
Answer:
U = max(ux, uy)
The Mann-Whitney U-test is a non-parametric test used to compare differences between two independent groups. The test statistic U is typically determined by calculating U values for both groups and selecting the maximum value to compare against critical values in the distribution table.
192
If a construction firm asserts that 40% of all new residences are 2-bedroom homes, what is the correct formulation of the null hypothesis?
Answer:
H0/P = 0.4
The null hypothesis (H0) represents the status quo or the claim being tested. Since the claim is that the proportion (P) of 2-bedroom homes is 40%, the null hypothesis is stated as P = 0.4. This serves as the baseline assumption against which the alternative hypothesis is evaluated during statistical testing.
193
What is the term for the systematic process of reviewing collected data to ensure it meets high quality standards?
Answer:
Validation
Data validation is the process of ensuring that data is clean, correct, and useful. It involves checking for errors, inconsistencies, and missing values to maintain the integrity of the dataset before analysis begins.
194
Evaluate the following statements regarding hypothesis testing: (I) A two-tailed test is required when the alternative hypothesis is Ha: μ ≠ μ0. (II) The mean of the sampling distribution of the mean is not equal to the population mean.
Answer:
Statement (I) is true, while statement (II) is false
Statement (I) is correct because a non-directional alternative hypothesis (μ ≠ μ0) necessitates a two-tailed test. Statement (II) is false because, according to the Central Limit Theorem, the mean of the sampling distribution of the sample mean is always equal to the population mean (μ), assuming the sample is unbiased.
195
What is the logical sequence of steps required to apply the Chi-square test effectively?
Answer:
1, 2, 3, 4
The application of the Chi-square test follows a structured process: first, collect random observations; second, ensure independence of sample members; third, verify that expected frequencies are sufficient (usually > 5 or 10) to avoid errors; and finally, ensure constraints are linear to maintain the validity of the statistical inference.
196
What is the primary purpose of using a Z-test when comparing two population means?
Answer:
equal
The Z-test is a statistical test used to determine whether the means of two populations are equal, assuming the population variances are known and the sample size is large. It tests the null hypothesis that there is no significant difference between the population means.
197
Which statistical principle states that as sample size increases, the results tend to become more reliable and accurate?
Answer:
Law of inertia of large numbers
The Law of Inertia of Large Numbers states that as the size of a sample increases, the variations in the sample tend to become more stable and representative of the population. This principle is fundamental to inferential statistics, as larger samples generally reduce the margin of error and increase the reliability of statistical estimates.
198
Statistics is defined as a numerical characteristic of a ________, whereas a parameter is a numerical characteristic of a ________.
Answer:
sample, universe
In statistics, a 'statistic' is a measure derived from sample data (e.g., sample mean), used to estimate a population characteristic. A 'parameter' is a fixed, true value that describes an entire population or universe (e.g., population mean). Therefore, statistics describe samples, and parameters describe populations or universes.
199
Which sampling method involves selecting the first unit randomly and then choosing subsequent units at fixed intervals?
Answer:
sequential sampling
The definition provided describes systematic sampling, where a starting point is chosen at random and every k-th element is selected thereafter. Note: The provided answer key indicates 'sequential sampling', which is technically different, so this is marked with a conflict flag.
200
Which of the following statistical methods are classified as parametric tests?
Answer:
1, 2, 3 and 4
Parametric tests assume normal distribution of data. T-tests, ANOVA, and linear regression are standard parametric tests. While Pearson correlation is parametric, it is often grouped with these. The source includes all as parametric, though rank correlation is typically non-parametric.