MCQ
Data collected through $.............$ method is reliable because it is directly collected from the respondents by the investigator himself.
- ATelephone interviews.
- ✓Direct personal interview.
- CIndirect oral interview.
- DNone of the above.
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
| S. No. | Method | Formula |
| (i) | Direct Method | $\text{r}=\frac{\Sigma\text{dxdy.n}-(\Sigma\text{dx})(\Sigma\text{dy})}{\sqrt{\Sigma\text{dx}^2.\text{n}(\Sigma\text{dx})^2(\sqrt{\Sigma\text{dy}^2-(\Sigma\text{dy})^2}}}$ |
| (ii) | Short-Cut Method | $\text{r}=\frac{\Sigma\text{xy}}{\text{n}.\sigma_\text{x}.\sigma_\text{y}}$ |
| (iii) | Step Deviation Method | $\text{r}=\frac{\text{dx'dy'.n}-(\Sigma\text{dx'})(\Sigma\text{dy'})}{\sqrt{\Sigma\text{dx'}.\text{n}(\Sigma\text{dx'})^2(\sqrt{\Sigma\text{dy'}-(\Sigma\text{dy'})^2}}}$ |